¶ Introduction
Hello friends! Today we're diving into a fascinating discussion about exercise intensity. Most of us have long accepted this simple guideline that one minute of vigorous exercise equals two minutes of moderate exercise. It's intuitive, neat, convenient, but what if it's fundamentally inaccurate? That rule has shaped global physical activity guidelines for decades, yet it was largely based on calorie burn, not hard endpoints like mortality, cardiovascular events, diabetes, or cancer.
Joining me to explore this important topic is endurance athlete Brady Homer, who has a master's in human performance and has collaborated with me before on the Found My Fitness Comprehensive Training Guide. Today we're breaking down a groundbreaking news study published in Nature Communications that used objective, device-based data to challenge decades of conventional exercise wisdom and guidelines. We break down the methods, the limitations, and what the data actually supports.
This is a journal club style episode. In this episode, Brady and I discuss how wearable accelerometers offer a more accurate picture of physical activity than traditional self-reported methods. The surprising new finding that one minute of vigorous exercise could offer health benefits equivalent to four to nine minutes of moderate exercise, dramatically altering our understanding of exercise efficiency.
Specific outcomes showing vigorous activity is up to eight times more potent for cardiovascular health and nearly ten times as effective in diabetes prevention. Why vigorous exercise uniquely triggers potent physiological adaptations like improved cardiovascular function, insulin sensitivity, mitochondrial health, and even reduced cancer risk through targeted cellular mechanisms. We talk about the practical implications for everyday life, including the powerful health habits.
a vigorous intermittent lifestyle physical activity. These are vilpas. They're quick, sometimes unstructured, everyday lifestyle ways that we're getting our heart rate up. But we also talk about the structured exercise snaps. This new research really could rewrite the existing exercise guidelines entirely. It challenges fitness trackers, challenges exercise apps and public health messaging. to completely recalibrate the way we value and measure physical activity.
Before we dive into today's episode, a quick reminder about our free evidence-based resource, how to train according to the expert. If you haven't downloaded this free guide yet, or even if you have, we just released major updates, you'll definitely want to check out. You can find that at howTotrainGuide.com. We've expanded our coverage on creatine supplementation with updated dosing protocols. We also have fresh insights into how it impacts brain health and cognitive function.
We've also refined our recommendations on exactly how much exercise is needed to maximize longevity, and also how exercise snacks and even Vilpas can contribute meaningfully to our fitness goals. So this guide really condenses the best evidence-based strategies from our leading scientists that have been on this podcast into a real single actionable toolkit. You'll find precise protocols in there for building muscle mass, building muscle strength.
targeted training methods that are proven to enhance cardiorespiratory fitness. This is a really important marker for longevity. We have updated science-driven strategies to support both metabolic health, cognitive performance, And then we also have some practical exercise routines that are really crafted for people with time-constrained schedules. Again, it's entirely free and it's available right now at howTotrainguide.com. Again, howTotraineguide.com.
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Thank you so much for supporting evidence-based health and fitness education. Now let's jump into today's episode. Welcome back to the podcast. Today we're going to be discussing this almost universally accepted rule that for every one minute of vigorous intensity exercise, that's equivalent to two minutes of moderate intensity exercise. And we're going to talk about
whether or not that's accurate and where it came from. So today's Podcast is more of a journal club type of episode where we're gonna be discussing a new study that really kind of overturns that idea. So I'm joined by endurance athlete Brady Homer, who has a master's in human performance. He's also an author of the book BO2 Max Essentials, and he's a former podcast guest. He was on the podcast.
a few months ago on the how to train according to the experts podcast where we were talking about our how to train guide, which Brady also was a collaborator on. So I'm pretty pumped to sit here and have this. first episode of a journal club for Found My Fitness. So, um
You know, hopefully we'll do more of these. So let's uh what do you think? Let's get started. For sure. Yeah. I think this will be a interesting new structure kind of for the podcast, new for, you know, some of our episodes. And I'm excited to see how it goes. Excited to talk about this study. I think it was really a
Eye-opening one in my mind. Um, so yeah, let's get into it. Eye-opening, but not surprising, right? Totally. So, okay, well, let's I'm gonna start off by just talking about what this.
¶ What exactly is the 1:2 rule for exercise intensity?
you know, one to two rule is for people'cause they might be like not exactly understanding what I'm talking about. So essentially, you know, For decades now we have these physical activity guidelines that's put out by the World Health Organization and, you know, other organizations that essentially state these physical activity guidelines, which essentially are
For optimal health, which is sort of vague, but for optimal health, you want to be engaging in about 150 minutes to 300 minutes of moderate intensity physical activity per week. Or if you're going to be doing more vigorous intense, um, vigorous type of physical activity, that would be more like 75 to 150 minutes.
So that's essentially your your you have this one to two rule, right? Where it's like, okay, for every one minute of vigorous intensity physical activity, you're gonna be doing two minutes of the moderate intensity activity. And that's kind of um where this rule came from. And I don't know that it's necessarily
It's not necessarily telling you if you're trying to reduce, you know, different disease risks, so cardiovascular disease or cancer, you know, fill in the blank, whatever disease. It's not really telling you that. It's just kind of like this is the guidelines, right?
¶ Calorie burn vs. longevity-origins of the 1:2 rule
So let's talk about the origin of this one to two rule. It really didn't come from direct measurements of health outcomes. Essentially, it's researchers that calculated, you know, for vigorous intensity exercise, you're burning about twice as many calories as you do for moderate intensity exercise. So it's really comes down to energy expenditure, not health outcomes. Yeah, and that was kind of like the biggest not surprise to me because I've, you know, known about this stuff for a long time but
When you really dig into it and it's like what what's the foundation of these recommendations? It is based on the idea of this thing called metabolic equivalent or metabolic equivalent of task. People maybe will um have heard that referred to as Mets or M E T S. And basically it is just what's the caloric expenditure of these various different activities? If you know you're doing a light activity. That might be somewhere between, you know, like zero to three mets.
Moderate activity, three to six mets, vigorous activity over six mets. And it's basically saying what's your oxygen consumption or your you know calorie burn during these activities. And so by that logic, yes, moderate activity, you burn, you know, that might be three to six mets. Well, if you're going harder than that, that's double the Mets, double the caloric expenditure. So you need half as much physical activity to get the same health benefit as.
The more moderate intensity activity. So that kind of formed the foundation of that either 75 to 150 minutes of vigorous, 150 to 300 minutes of moderate. And it makes sense, logically, but as you just said, you know, well For for what? What health outcomes are we looking at? Are we just focused on calorie burn? So yes, if if we it's just focused on calorie burn, yes, the two are equivalent.
But health is a lot more, as you know, than just burning calories. Um, people are focused on different health outcomes like improving their fitness or improving their cardiovascular health, improving their diabetes risk. So when you look at it from that perspective, it really changes the way that you think of
Well, maybe it's not all just about metabolic equivalence. Maybe it's about something different and we should be looking at the value of physical activity um in different ways. Right. Um I think that's a really good point because I think people that are more focused on weight loss. aren't necessarily the people that are looking at the physical activity guidelines. Right. Those are the people that are
counting calories and they're, you know, it it's a very different, they're trying to figure out how much exercise they need to do to trim down body recomposition. Whereas people that are actually looking at the physical activity health guidelines generally in their mind have this concept of
How much exercise do I need to like age better? Right? Like that's generally what people are thinking when they're looking at these guidelines. How much exercise do I need to do to really age better? And so i it's it's kind of unfair because, you know, these guidelines if they not aren't necessarily
indicating how much exercise we need to do or what what type of exercise we need to do t to really age better, um, then it's time to change these guidelines. And I think we're gonna talk a lot about that. But I also wanted to mention
¶ What counts as 'vigorous' exercise, really?
You know, you're talking about these metabolic equivalents with respect to light, moderate or vigorous, you know, intensity physical activity. There's some examples for the guidelines that are given, which aren't necessarily what I would think of as moderate or or vigorous. So for example, they say light activity is a casual stroll or maybe like you're standing, so just not sitting, or you're maybe you're washing dishes.
And then the moderate activity is like brisk walking. So you're walking more briskly or you're you're maybe doing a leisurely cycle, you're doing some yard work. That's considered m considered moderate intensity physical activity.
And then vigorous activity is running, swimming, more recreational sports, or if you're like, you know, playing with your kids outside, sprinting around, playing with your puppy or your dog. So those those are sort of some of the guidelines, you know, f in terms of how you define light, moderate, or vigorous physical activity. Um Yeah, and I do think that's important.
for framing kind of when we start to talk about this study, for framing our discussion today, because when people hear vigorous, especially, you know, as you usually talk about on your podcast, it's vigorous intensity is kind of this high intensity interval training. But when it comes to the guidelines, vigorous is a lot
less vigorous and people are probably familiar with zone two training. I would just consider like when you hear vigorous in the context of this discussion or the physical activity guidelines, that's like zone two intensity or above basically. So it includes high intensity interval training. But it also includes things that are a little less intense than one might consider high intensity interval training to be. Right. Yeah. So typically
You know, especially in this podcast I've talked a lot about vigorous intensity exercise and with regards to like heart rate measurements, right? Like people are wearing these wearable devices and they're measuring the heart rate and usually it's like you're getting into the eighty percent max heart rate or above, you know, and and I
i like you said, you know, it's it's really not n that includes vigorous, yes, but like Especially when we get into this study that we're gonna talk about today and looking at the physical activity guidelines in general, vigorous. is a little bit less than that. So it does include more of that zone two type of training. But you are running. You are able to maybe have you know, say a few sentences while they may be breathy, you can still state them. That's actually considered vigorous.
if we're actually just talking about the physical activity guidelines. Yeah. Very important. And then also just, you know, I think we s sort of already stated this, but just to kind of reiterate
¶ Where the exercise guidelines fall short
Talking about the potential flaws of the physical activity guidelines is one potential like looking at long-term like health outcomes, right? Two would be like re r relying on self-reported data. And that's something that we're gonna get into today, you know, when you're trying to ask people to remember their physical activity and you're gonna talk about this a little bit more, um, it's just not accurate. And then the third one would be that it's not it's not actually able to capture
Um, some of these like, you know, you're playing with your kids or you're you're sprinting around with your puppy, right? These short bursts of physical activity that do matter, right? So you're not you're not including that as well.
¶ Can your wearable predict disease risk years in advance?
So why don't we get into this new study? It was published published in Nature Communications, wearable device based date wearable device-based health equivalents of different physical activity intensities against mortality, cardiometabolic disease, and cancer. Very good study. Um, maybe we can kind of start off with, you know, the
how the study was set up, like some of the methods. Yeah, sure. So this was by um it was by a group led by Stematakis as the first kind of author on it. And importantly they're the
They're the group behind a lot of these Vilpa studies, Rhonda, that you've talked about a lot, the vigorous intermittent lifestyle physical activity studies. So they authored this study and they mine data from the UK Biobank. That's just a huge it's kind of similar to like the NHANES in the United States where Just but lot cohort of a ton of individuals looked at for, you know,
decades or more. Um they have all this health data on them, objective data, subjective data. So for this study they focused on um seventy three thousand, more than seventy three thousand adults. from the UK Biobank who were aged forty to seventy nine. So that's kind of important, I think, as well. They were, you know, middle aged to to older age to adults.
And they tracked them over eight years. So the follow-up period in the study was eight years on average. Um And the important part of the study is how they measured their physical activity. It was measured using these wearable devices, these wrist-worn accelerometers. They wore it for a week at the baseline of the study. And so then they took all their physical activity from that one week. And then, you know, that was used to establish these physical activity levels for these individuals.
Kind of a limitation there, obviously physical activity was only measured for a week using these accelerometers, but You know, as we'll maybe discuss later, uh it seems like a limitation, but in a way I almost feel like it's a strength because the strong association with these health outcomes almost assumes that this activity that they were doing during that one week may have been consistent over, you know, the pr next eight years or or something like that. Um
So it's also I mean, y we it's measuring everything, right? It's measuring the short burst of exercise that you would never think about. Like if someone were to ask me how many minutes I exercise a week, I would only include my structured, defined workouts that I set aside to work out. I wouldn't include You know, the three times a day I'm sprinting around my yard with my puppy, or, you know, once a day that I'm playing soccer with my son.
I don't include those, but I'm absolutely getting my heart rate up. Right. And that was I think the major strength of this study. So instead of self report, which a lot of the previous studies for the guidelines did. This one was objective data and yes, it captured it captured what physical activity they were doing, what exercise they were doing, I guess. So they're structured workouts, but also as you mentioned, just
everything they did throughout the day. This device was measuring every single activity in ten second bursts throughout the day. Every ten seconds it measured, you know, what is the intensity that their activity is. And
I don't think can we pause for a minute when you say what the intensity of their activity is and your accelerometer, right? Yeah. So people might be confused and they again might be going back to heart rate. Like when they hear wearable device and they're thinking intensity. I know my brain goes right there, like heart rate. Can you kind of explain like how they were able to define light, moderate, and you know, vigorous with this accelerometer data?
I'll do it the best that I can without getting like way too complicated on how the accelerometers measure physical activity, so yes. Not intensity not based on heart rate in this study, which would be the common convention and maybe your wearables measure that using, you know, heart rate, the wearables we have today, like your, you know, Apple Watch. So an accelerometer is literally a device that you wear on your wrist and
It is measuring the direction of movement and the physical intensity of movement. So if I move my wrist, say slowly, that might be light activity intensity, light intensity activity. If I move it more vigorously, that might be vigorous intensity. So this accelerometer device is measuring, you know, the intensity of people's movements throughout the day.
the direction of that intensity because it just has this physical, you know, an accelerometer in it, which just measures the direction and the intensity of physical activity. And so every 10 seconds throughout the day, it's measuring their intensity of physical activity. And then based on a certain threshold of how intense their movement is. that would get bucketed into being a light intensity activity, a moderate intensity activity, or a vigorous intensity activity.
So every 10 seconds this thing is measuring, you know, what type of activity you're doing. It gets bucketed into one of those three intensities and then summed throughout the day and then throughout the week to say you did this much vigorous, this much moderate, and this much light activity.
So it's a little bit difficult because most of the devices we have these days are not accelerometer based. They're either heart rate based or they're you know, you're actually using a GPS like most of these devices. But I think that's the best way of describing it. But the important thing there is that
This is how the intensity was measured in this study, not using, say, something like a heart rate. What I what I was thinking about, um when when kind of r reading the paper and like t talking about it with you is how it would categorize like let's say someone was like doing bicep curls, right?'Cause your wrist is moving, but you're not really walking, you're not really moving distance wise.
So is that something that would be picked up by this device and considered and what bucket would it be?'Cause like some people can be like moving fast, right? It would and that would be I think even regardless of the um speed at which you were moving that dumbbell, that would probably be categorized as like a vigorous intensity activity because it's purposeful movement and you know it's
you know, the force and the torque at which you're measuring your arm. So that would be probably categorized as a vigorous intensity activity. It doesn't necessarily matter whether you're moving physically forward or backward in space. It's just like what is the um speed or the intensity at which your body is is kind of moving.
Okay. So yeah, a little bit complicated, but you know, that's the best way to describe it without considering that, yeah. I mean considering that because you know, the a lot of times when people hear the word vigorous intensity, you know, activity, they're not really thinking of resistance training.
¶ Is vigorous activity easier to achieve than people think?
So maybe like you can give some examples, at least I know the study laid out some examples with respect to what's actually considered you know, vigorous versus moderate versus light. And then um obviously we talked about what what examples are considered that for the health guidelines, but they're pretty similar. They are similar. This study they said, you know, light activity, they gave some examples of it that would be
just uh light household chores, so even maybe you're um, you know, emptying the dishwasher or sweeping or vacuuming or something like that. That would be considered like light activity based on this study. Moderate activity would be something like actively commuting. So say you were Riding your bike leisurely to work, or you were commuting to work, walking from the bus to work, going up some stairs, doing maybe some more moderate household chores.
And then vigorous, they gave some examples like, you know, outside playing with your kids or you're you're running or you're riding a bike or exercise. Exercise would be categorized into that vigorous bow but all or that vigorous type of activity. But really anything, you know, purposeful movement I think is You know we're chatting offline and
Anything that would be purposeful movement, you're doing this for a reason of, you know, either to exercise or to get somewhere, that would kind of be considered vigorous in this study. So again, like the guidelines, maybe a little bit less. Than what people imagine when they think of vigorous, which I think is kind of cool because when we start to discuss.
The benefits that vigorous activity had, it goes to show just the power that even kind of purposeful movement, even if it's not high intensity interval training, could have. Yeah. And I think it is important to point out like physical activity versus exercise because people do typically when they think when they hear even physical activity, they think
you know, structured exercise. It's a very I think a very common, you know, thought is structured exercise is physical activity. But it's not necessarily structured exercise. It includes it, but it can also include all the things that you mentioned, where you're, you know, playing with your kids or you're playing with your dog or you're
um sprinting up the stairs, you're walking to work or things like that. Like this is all physical activity. And that's what this is all capturing. For sure. And it it's kind of interesting when you think about that too, because when we talk about the guidelines, I think a lot of people hear that and say,
Hundred and fifty to three hundred minutes of physical activity a week, that means I need to be in the gym for 150 minutes to three hundred minutes. But again, physical activity is different than exercise. Physical activity is any physical activity you're doing throughout the day, exercise is Defined, structured,
a workout, like a training regimen that you, you know, go to the gym and you set aside time for. But physical activity can be things done throughout the day, just integrated into your daily life as well. Right, right. Um okay, so health outcomes that were tracked in this study.
¶ How researchers avoided the 'healthy user bias'
We have do you want to mention the health outcomes? They pretty much tracked anything people are interested in in terms of health, so all cause mortality, death from any cause. Most people are aware of what that is. Cardiovascular disease mortality, so deaths from anything related to cardiovascular disease, heart attack, stroke specifically, um major adverse cardiovascular events or mace, so that's heart attack, stroke, cardiovascular death.
Um type 2 diabetes incidents and then cancer incidents and that included physical activity uh related cancers as well. Um and one of the important points too about these health outcomes. Is that a lot of the problems with some of the previous studies were it's this idea of the healthy user bias. Um, so oh, people who are more physically active. Do they have lower disease risk or do people who have less disease
do more activity. Well, they controlled for that in this study by excluding people who, if you developed any of these diseases within the first 12 months of the study, they were excluded. And additionally anybody with a disease at baseline was excluded. So they tried their best to sort of take care of this.
sick user or healthy user bias, which I think strengthens a lot of the the outcomes in the study. That's a really uh important point. Um okay, so I'm gonna I'm gonna kinda get into some of these
¶ Health equivalence ratio-a better way to measure exercise benefits?
major findings in the study. And I think before getting into that, um, I just want to talk about that when we're when we're talking about the minutes to reduce all cause mortality or cardiovascular related mortality or cancer related mortality. Generally they were talking about this range between five to thirty five percent risk reduction.
in in, you know, reducing those mortality rates or disease incidence in the case of type two diabetes. Um, you could go above that and we'll get into that when we talk about dose response, but I just want people to kind of be aware of that's kind of like the range
that we're talking about here is like anywhere anywhere between five to thirty five percent like risk reduction. Yeah. And I think the main thing too then to also mention before you get into the risk reduction was and this was I think the most unique aspect of the study is they calculated something called the health equivalence ratio. So basically what they wanted to know in this study was
How many minutes of light activity or vigorous activity do you need to do to get the equivalent amount of risk reduction to a minute of vigorous intensity activity? So it was this they c called it the health equivalence ratio in this study. They b they were basically looking at, you know.
Does this one to two going back to the one to two rule that we talked about, does this one to two rule hold up? Do you need if you do twice as much um moderate activity, does it give you the same disease reduction as a moder a minute of vigorous or is there like this skewed ratio? Is there more vigorous activity? You know, does that give you more risk reduction compared to a minute of, you know, lighter moderate activity? So
When we're talking about it, you know, a lot of these studies just look at risk reduction at X level of physical activity. One of my favorite parts of this study was this health equivalence ratio thing that we're gonna talk about because it really um sheds some light on the impact of vigorous activity. That's great. I love it. Um, okay, so I think the biggest headline from this study was that vigorous intensity, physical activity was.
¶ Is vigorous exercise truly 4-10x more effective?
It wasn't a two to you know, it wasn't twice as better than moderate intensity, right? We're talking anywhere between four times better to almost ten times better than moderate intensity exercise, which is Pretty big. Um so first of all when it comes to all cause mortality. It seems as though one minute of vigorous intensity physical activity was equivalent to about four minutes of moderate intensity activity. So basically
in terms of reducing all cause mortality, right? So this is the death from all non non accidental causes, right? And um if you think about that, you know, vigorous intensity physical activity is four times as potent in terms of, you know, you can get the bigger bang for your buck. four times as potent at at reducing the risk of all-cause mortality than moderate intensity physical activity. That's pretty big. Um but it actually gets even bigger when we look at cardiovascular related mortality.
And this is a really, really important point because, you know, cardiovascular disease is the number one cause of death in the United States in many developed nations, including you many European nations. Um, so It's something that's really, really important. And what I'm about to say will blow people's minds. I know it blew mine, and that is that vigorous intensity physical activity, you know, for every one minute of vigorous intensity physical activity you had to perform
7.8 minutes, almost eight minutes of moderate intensity physical activity to get the same reduction, risk reduction in cardiovascular-related mortality. I mean, that is insane, you know. So It it kind of like, you know, if you're thinking about I'm spending seventy five minutes doing mod uh sorry, doing intense, like more vigorous types of exercise, your running or cycling or whatever.
And you're thinking about that and go, how much time will I have to spend doing moderate intensity physical activity to get that same benefit, health benefit on reducing my cardiovascular disease mortality risk? You'd have to you'd have to multiply it by essentially eight. And that's huge, right?
Another big one is type 2 diabetes, so this one isn't so surprising to me either and probably not to you as well. Um vigorous for every one minute of vigorous intensity physical activity, you had to spend about 9.4 minutes. Doing moderate intensity physical activity. So it's almost 10 times as powerful at reducing the risk of developing type 2 diabetes. And it's really not it's it it's not that um surprising because we do know that exercise intensity really does drive a lot of the metabolic
adaptations and benefits that occur from exercise with respect to improving insulin sensitivity and blood glucose regulation and whatnot. But I mean ten times, nearly ten times, right? That's not Um and then the last big uh I would say headline here with respect to comparing vigorous to moderate
is cancer mortality. So for every one minute of vigorous intensity physical activity, you had to spend about 3.4 or 3.5 minutes um doing moderate intensity physical activity to get the same reduction in cancer mortality. So still underestimating, you know, if you're looking at the physical activity guidelines, underestimating the effect that vigorous intensity physical activity has on every single health outcome. You know, I mean it's just I feel like if people were to think about it like this.
they would get so much more dopamine from their like more vigorous workouts where they would just be like, this is really doing something, you know, this is really doing something beneficial for my overall health and for like the way I ate. Um and I think maybe that's something we talk about later, but I just think that this could and probably should change the way like these wearable device companies program their algorithms and program their the way they like gamify physical activity almost to
enhance the um you know the rewarding aspects of the activity that you're doing. No, yeah, definitely. Definitely. We should talk about that and I a hundred percent agree. Um, but before we get there,
¶ Can one vigorous minute match an hour of gentle walking?
Let's you're they're gonna talk a little bit more about the insane difference between vigorous physical activity and light physical activity. I mean it's It's so crazy to think about um the difference between those that i the time efficiency is like you just you can't
You can't ignore you can't ignore how efficient, vigorous physical activity is. Yeah, some of these numbers were kind of incredible in the study and like some sometimes you look at'em you're like, does this like make any sense? But the numbers were insane for the
health equivalence ratio of this light activity. Now moving from what you were just talking about moderate to what's the equivalence of light activity to vigorous activity. So For all the main outcomes, including cancer light activity, one minute of vigorous activity was equal to 53 to 94 minutes. um of light activity. So to get the same mortality risk reduction as one minute of
Uh running, you might need, say, an hour or so of gentle walking, just kind of using a practical example there. Wait, just pause for a minute. One minute of vigorous physical activity. So let's you know, let's just listen to this. An hour equivalent to an hour of like gentle walking. Time efficient right there. For sure. Um, for diabetes prevention, it was nearly an hour and a half. So 94 minutes of light activity was equal to one minute of vigorous uh intensity activity.
For the cardiovascular disease outcomes, um 73 minutes for cardiovascular disease disease mortality, 86 minutes for um major adverse cardiovascular events. And then for cancer mortality, this one was the largest one. Um, one minute of vigorous activity was equal to 156 minutes, so nearly two and a half hours.
of light intensity um activity. So I think all those numbers, again, they seem a little bit extreme, but you know, that's what the data were showing. And I just think it goes to show that even like as we just talked about, not even high intensity interval training, just vigorous, purposeful kind of efforts, zone two or above, have this massively outsized be benefit on health outcomes compared to light intensity activity.
And I think, you know, this I think, you know, you and I have talked about high intensity before and this isn't to say that the light intensity activity is useless. Um, obviously any m we both agree any movement is better than just sitting around. Um but
¶ Why vigorous activity-not gentle-offers dose-dependent benefits
The study did find some benefits. So for all-cause mortality and diabetes prevention, there were some benefits to doing more light intensity activity. Um, but there were some outcomes, so say for cardiovascular disease mortality, stroke, heart attack.
it actually didn't really seem to have much of a benefit. Doing more light intensity physical activity didn't significantly reduce. So there were, you know, five to ten percent risk reductions, which the authors actually didn't consider to be meaningful in the context of this study. So Doing more physical activity if it were light didn't seem to produce uh extra risk reduction for a lot of these outcomes, other than diabetes and all cause mortality reduction, which I think
is kind of important to uh point out. There was a quote in the study from the authors. They said Not even the largest amounts of daily LPA or low intensity physical activity can elicit the health benefits of moderate or vigorous intensity. So I think that tells us kind of all we need to know about the study. That was kind of a very apt conclusion. Yeah, I I I agree. I mean I think I think I was reading in the paper that, you know, it was it the for light
physical activity it was capped at like fifteen percent. You got like a fifteen percent reduction in, you know, cardiovascular related mortality and some of these things. But like You know, it just it didn't go beyond that. Even if you did hours and hours and hours, that's like that's what you were capped at, or like ten percent for cancer or something like that. So it's like again, you're just like, you know
You just you could for hours be doing light physical activity and you're only gonna get that like ten percent cap. Right. There wasn't really uh there wasn't really a dose response, a potent dose response observed in the study. Whereas um with the vigorous intensity physical activity there was, but like before I m I get to that I do wanna I did forget to mention um the risk of
¶ Is vigorous exercise 5x better at preventing heart attacks & strokes?
having a heart attack or having a stroke. So these are these adverse events you were talking about with vigorous intensity physical activity. for every one minute of that vigorous activity, you needed about um five point four minutes of moderate intensity activity. So again, you know
Heart attacks, strokes, like those are major events that you want to avoid. And so you know, f you could you could you could be so much more time efficient if you're doing vigorous physical activity versus the moderate even. And certainly light. I mean, that's like Again, I don't wanna like you said
¶ Why vigorous activity stands out for cancer prevention
S being sedentary is a disease. We know that being sedentary is an independent risk factor, um, particularly for cancer. And I think that was where you were saying there was actually more was it. Uh it was uh let's see. I think it was just for all cause mortality and diabetes was for light activity. Cancer. Cancer did have that huge equivalence when it came to the light versus vigorous. It was like two hundred hundred and fifty six minutes, I think, of
little light activity you needed for the risk reduction of virus. Um but yeah, no dose response for cancer for light activity either. Right. Um but yeah, so be so being sedentary is bad. So anything that makes you not sedentary is better.
¶ Does zone 2 qualify as vigorous exercise?
But I mean, if we really if we're talking about being physically active, I'm gonna be s I'm gonna be honest. I think we need to be talking about at least moderate at least. Preferably vigorous. And in fact, vigorous it doesn't even have to be as vigorous as we usually talk about on this podcast. I mean, we're talking I talk about a lot about the the benefits of going high intensity for the brain and all the, you know, it is still time efficient, but
But right now we're talking about vigorous and it has a little bit of a wider range, right? So a little more room. Yeah. Which I think is a I think is kind of liberating as well because we're not saying Oh my god, you need to do 300 minutes of high-intensity interval training with the right. The Norwegian four by four. And yeah, exactly. The Norwegian four by four. It's you just I mean, if you get
that amount of zone two just exercise is is beneficial. So it's not we'll maybe you know, t we'll talk about this later too, but yeah, it doesn't y you don't need to be doing constantly hit. It's just these crazy benefits with this purposeful zone two even intensity movement is pretty pretty incredible. It's that we're really just dramatically underestimating the power of
doing exercise, you know, and and getting our heart rate up. I know we're not measuring heart rate, but essentially they do correlate, right? Um with the dose response curves with vigorous exercise, we did see a linear
¶ Dose-response comparison-vigorous vs. moderate vs. light activity
effect, both vigorous and moderate intensity both, but with the vigorous I know that you could spend about thirty to forty minutes per day doing this vigorous type of exercise. And that was associated with fifty percent or more greater reduction in like many of these categories for health outcomes, you know, cardiovascular related mortality, all cause mortality. So uh type two diab diabetes incidents, right? Fifty percent or more like
reduction. That's pretty robust. And again, that was at the higher end of the vigorous intensity physical activity. Um but there's definitely a dose response that that was seen there. Yep. And with moderate too. So up to about fifty minutes per day you kind of saw this linear dose response of this risk reduction up to about fifty minutes per day of moderate activity and then after that
You didn't see more risk reduction basically from getting more moderate activity. And then moving on to the light activity, as we sort of al already just mentioned, not much of or zero dose response relationship. So you do some light activity, you get about a ten to fifteen percent risk reduction, but Doing more of that up to say even two to three hours a day of that extra light activity didn't really seem to reduce risk much more. Right.
Um, okay, so let's I think that's pretty clear that we're dramatically underestimating the value of vigorous intensity physical activity in ret in terms of reducing the risk of a variety of different, you know, negative health outcomes, right? And so
¶ Is vigorous exercise the secret to younger arteries?
That's pretty clear, but the question is why is that? Right. And this is something that I would say. We've Sort of talked about on the podcast before, I've had a lot of different exercise physiologist, Ben Liv D Dr. Ben Levine, Dr. Martin Kabbalah on the podcast, and we've talked a lot about the adaptations to physical activity. Um so I wanna kind of start off with the effects on cardiovascular health and the adaptations that occur.
in the cardiovascular system, because I think it's probably one of the most important concepts here. And um it does really come down to this idea of The stronger the stimulus is, the greater the adaptation, right? Now, obviously, you can always take something to the extreme case. Right. If you were to exercise all the time nonstop, like that's not good. But we're not talking about that. So the stronger the stimulus, the better better the adaptation. And
One of just to kind of reiterate to people before we talk about the adaptations, you know, remember one minute of vigorous physical activity was equivalent to almost eight times, right? So eight minutes. of moderate intensity physical activity. That's big difference. Um And so one of the big adaptations here really comes down to increased blood flow.
It's just getting your blood pumping, moving, because what happens is they're cause this causes what's called sheer stress on your vascular system, on the interior lining of the arteries. And what shear stress is, is essentially just the friction of the blood flow against this interior lining of the arteries and the vascular system, right? There's a friction there.
And so the stronger the exercise, the more vigorous the exercise, the faster your heart is pumping, and that's why heart rate does come into this, the the more your blood flow is moving, right? So you're getting a stronger shear stress. And that is actually not a bad type of stress. It's a good type of stress. The sheer stress causes your endothelial cells lining your arteries to adapt.
um and in a way where it improves vascular function, it improves endothelial function, and it causes these endothelial cells to secrete beneficial molecules. So one of those would be nitric oxide. Many people have heard of that. And the other one would be prostacycline. And both of these compounds are causing vasodilation, you know, they're improving blood flow. But over time, and as you continue to repeat this sheer stress. What happens is you're improving
the flexibility of your arteries, you're making them more resilient. They're able to handle stress better. You're improving their overall functioning and you're making them more resilient and resistant to atherosclerosis. Right. And that is Essentially. I think at the crux of what's going on here with respect to why vigorous intensity exercise is so beneficial for cardiovascular health.
Um, we know Dr. Levine has come on the podcast and talked about, you know, some of the benefits of doing more vigorous intensity exercise and how you get more stronger cardiovascular adaptations. And if we look at even that study he did in middle-aged adults. where he took, you know, fifty year olds and put them on a pretty, you know th I would say the exercise program, if you if you look at look at it, it was like all all vigorous according to this definition of vigorous.
Um and it was what, five hours a week? Mm-hmm. About five hours a week. Five to six hours a week at the time. Right. And and so if we're if we're talking about the definition in this study, it was pretty much all vigorous because they were
either running, doing like a zone two type of run, or they were doing Norwegian four by four, some high intensity interval training, some resistance training in there. And after two years they reversed the structural aging of the heart by about twenty years. You know, and that's pretty profound. So the cardiovascular adaptations are real. They are real. Um Yeah. And I mean a lot of the if you read any of the randomized controlled trials to just comparing
Moderate intensity training to high intensity interval training. If you look at the effects on endothelial function, like you mentioned, and artery stiffness, it It's not it doesn't even come close, like when even when their volume matched, so you say you do
the same amount of volume of moderate intensity and high intensity interval training. It's high intensity interval training always wins in terms of improving vascular function. And it's just it all comes down to really that sheer stress that you mentioned. It's so
Higher intensity, more shear stress, it's bet it's good. Shear stress is almost like a bad name for it. Cause like you said, it's kind of sounds bad. You don't want shear stress, but like you do. The more shear stress you get, the better. And it's not just a simple dose respon it's just not uh like a area under the curve, I guess, type of thing. It's
You can't just do more low intensity because you're not getting the it's the intensity of the shear stress, not the amount over time that actually matters for those endothelial adaptations. So it's really important to do HIT uh in that respect for sure. That's a really good point'cause it's kind of like thinking of A light breeze.
Blowing across your face versus a strong wind. Yeah. Right. Like there's a difference between a light like you can't have a you could have a light breeze last for a really long time, but it ain't gonna knock over some trees, right? Like it's not gonna like you need that you need that stronger wind. And that's what you need.
with the sheer stress in your vascular system. It needs to be stronger to ha to cause, you know, to basically signal to your body, hey, this is stressful. Let's respond to that stress. But it's not so stressful. It's not a heart attack kind of stress, right? Like that's too much stress, right? It's just enough to like give you these adaptations so that.
when you have really stressful s situations happening, your your your arteries and your vascular system respond better, right? So, um I really like that you pointed that out. Let's let's talk about, you know, how
¶ Why aging hearts need intensity
heart and lung function together, right? Like the cardiorespiratory s you know, system and how vigorous intensity activity really plays a role there as well. Yeah. So I think similar to kind of the cardiovascular stress, the endothelial stress, higher intensities o of exercise are going to increase, you know, metabolic demand, increase your oxygen demand in your muscles, which is going to force your body to
Ne it needs to deliver more oxygen to your working muscles. That means your heart is gonna work harder, your stroke volume is gonna go up. So stroke volume for people who may not be familiar, it's the amount of blood that your heart is pumping out per beat. So it fills with blood and it pumps it out and
in usually expressed in something like liters per minute. That would be your your stroke volume. It forces your stroke volume to go up. Your heart rate obviously goes up during more vigorous exercise. But also your lungs are gonna fill and, you know, be stressed more to deliver more of that oxygen to your body. And so
That's another one of these reasons why vigorous and, you know, even zone two intensity of of exercise up to a point, they're gonna stress the cardio the cardiac system, the heart and the lungs more. That's gonna force your body to adapt and your heart is gonna get stronger, your lungs are gonna get stronger.
And I think one of the key adaptations there is obviously again the the increase in in stroke volume that you get. That's one of the best predictors or that's the main thing that increases when VO two max increases. So if you look at these studies Showing, you know, what's the main adaptation that gives you a better VO2 max? It's higher stroke volume because that gives you a greater cardiac output. Your heart can pump more blood to your body. you can use more oxygen during exercise.
And so that's one of the reasons why HIT is so effective because it increases your oxygen demand more. It forces your heart to work harder and you're improving that that stroke volume. And then same thing with the lungs. I think the lungs are a little bit
not less adaptable, but they do adapt less because in a lot of people, unless you have asthma or something like that, the lungs are a little overbuilt, uh, maybe for exercise. Like most of us have plenty of lung function, but the heart is really what's gonna adapt there. And so I think that, you know, again is why we see this efficiency with his vigorous e intensity exercise in this study and in others, because
you're just the heart is being stressed worn. You're gonna have a stronger heart if you're engaging in more higher intensity activities that are forcing the heart to adapt. Going back to Ben Levine, I think he cited, you know, that similar study, but He talked about how, especially after say age 50, 60, 70, you need these higher intensities. Again, it doesn't have to be hit, but it has to be pretty vigorous.
To force the heart to adapt and prevent cardiac fibrosis, cardiac stiffening of the heart. If you don't get that high intensity training, Um, you know, like low intensity really just doesn't cut it. And so, you know, in this study, the cohort that we're talking about, they were aged forty to seventy-nine. So that might be why vigorous exercise had this outsized benefit on specifically cardiovascular outcomes, that eight to one ratio, like you mentioned, that incredible
like m higher than s some of these other outcomes. Um so I think that's why there was that outside's benefit as well. Yeah. I think for people um with respect to like why is it important to improve your VO two max, you know, your cardio respiratory fitness, that being a pretty
¶ Can vigorous exercise halt your VO₂ max decline?
important marker for longevity and you know, for lowering your your risk of death from all causes of mortality, right? So essentially like we've talked about this before last podcast we did together, right? We're people with the highest cardiorespiratory fitness as measured by VO2 max. they had a five year increase life expectancy compared to the lowest people with the lower or lowest. cardiorespiratory fitness or
the eight they had a l eighty percent lower all cause mortality, right? So any way you look at it, you know, if you are in that higher cardiorespiratory fitness range, you are talking about you know, a a lifespan, life expectancy, you know, extension if you compare it to if you were not in that in that range. For sure. And after about age thirty to forty into your fifties, your VOT max starts to decline about ten percent per decade. So if you're not doing
Something to maintain that. Yes, you can build it up as much as you can into your thirties and forties, but If you aren't engaging in moderate to vigorous intensity exercises at age 40, 50, 60, 70, Your VOT max is just gonna continue to drop ten percent per decade. The only way to maintain that or even build that is to do these more vigorous types of exercise. Yeah. And I I think this is kind of important again, you know.
¶ Why moderate exercise alone might not improve VO₂ max
I know people are gonna be confused because we've talked about vigorous intensity exercise in such a different context than this study and also than the physical health guidelines. And, you know, I just going back to this study that um Marty Gabbala cited on the podcast a c a few years ago where he talked about, you know, forty percent of people that are meeting the guidelines for moderate intensity physical activity.
So that would be 150 minutes to 300 minutes a week doing this what is defined as moderate intensity activity, right? Um, they are unable to continue to to improve their their cardiorespiratory fitness, their VO2 max. um unless they're engaging in more vigorous types of exercise. So again, in this regard, it seems as though the vigorous intensity exercises is is not as vigorous as perhaps once thought.
Right. What are your what are your thoughts on that? Yeah, I I would agree. And I think one of the reasons maybe why we're seeing that signal there is because when we talked about the methodology of the study These devices were capturing all the activity that they were doing throughout the day. And you and I are gonna talk about, I think, exercise snacks in Vilpa a little bit later. And I think that's why we're seeing this extra added benefit of this vigorous and moderate activity is because
This device was capturing everything, not just those intense those sessions that people remembered. So it was really getting like the full spectrum of activity throughout the day and seeing this massive risk reduction. But yes, I mean
W with regard to the non responders thing, I think that specifically might refer to, you know, adding some deliberate high intensity interval training into your, you know, uh, schedule during the day. But yeah, um I think it's another illustration of how just like the low intensity kind of uh doesn't cut it and the guidelines.
You know, some people don't respond well to the guidelines and we either need an update or you need to do more or probably some combination of the both. Yeah. M more emphasis on on vigorous, I think, too, as well. Um okay, so some of the other adaptations. Let's talk about, you know, the type two diabetes, lowering the new diagnosis of type two diabetes was very profound, right? Here we're talking about almost
¶ Is vigorous exercise 10x more powerful at preventing diabetes?
Vigorous intensity was almost ten times as effective, right? That's big. So why is that? And again, that is something that I've talked about a lot in I did a podcast, like a solo cast on vigorous intensity exercise. and talked about, you know, why vigorous intensity seems to be really key uh for improving metabolic health. Um when, you know, when you are working harder, when you're working your muscles harder, um when you're when you're basically forcing your muscles to
produce energy quicker, um what ends up happening is you're not using your mitochondria all the time. You're sometimes you're gonna be using your mitochondria, but you're sometimes going to be making energy without them as well. And so you're gonna be making something called lactate. as a quote unquote by product, which is not necessarily a by product, it's an active metabolite.
And why is that important? Because lactate is not only a metabolite, in some in some ways it actually acts as a hormone. It is a signaling molecule that's signaling to, you know, other proteins, to other organs. to to basically work harder and like respond to this hard work that is going on, right? So, um, with improved insul insulin sensitivity, we do know that vigorous intensity exercise, for one, it does cause your muscles to contract, right? So you can actually
just in and of that of itself. If your muscles are um, you know, contracting, you can basically cause fifty to a hundred times more um contractions than At rest. That's a lot, right? And that actually forces glucose to come into your muscle. So your muscle is a big sink for glucose. But your muscle also has to transport that glucose across it. And that's where lactate comes in because when you're working hard, you are produ your muscles are producing lactate.
And that lactate essentially signals to your muscle to increase these GLUT4 transporters. These are the transporters that are responsible for bringing glucose out of your circulation and pulling it into the muscle. And um and so lactate's actually what is responsible for that, for that, you know, signaling to increase the GLUT4 number or translocation to the cell surface, muscle cell surface. Um and so what happens is that you're basically with a more intense
or the more vigorous intensity the activity, the more glucose you're gonna bring in because you're having more of those transporters there and the transporters actually last around for a while. So there's a lasting effect. It's not like they just They're there when you're working out and then they go back. No, they stay active for quite a while, right? Bringing more glucose in. And so it's it's un it's unbelievable to um to to actually think about how beneficial vigorous
intensity activity is if you're thinking about, you know, a ten times efficient. I've seen Now I know that um there's been a couple of studies showing that vigorous intensity activity, you can do like fifteen minutes of vigorous intensity activity and that's equivalent to like forty-five minutes of moderate intensity in terms of um glucose regulation.
I would say there's even other studies out there showing like a one to five ratio as well. But this study itself, if we're talking about outcome, not just biomarker data, we're talking about outcomes. So we're talking about new diagnosis of diabetes.
It suggested a one to ten ratio, almost. It was 9.4, but almost one to ten. Um, so I really do think that this confirms that, you know, obviously we've looked at a lot of biomarker data with these randomized controlled trials. We've had Marty Kabbalah on the podcast talking about
you know, tons of these the you know trials you know showing that if you do high intensity interval training For volume matched, moderate intensity continuous exercise, you will get improvements in insulin sensitivity and blood glucose regulation and a lot of different metabolic markers.
Um again, volume matched. Um it wasn't necessarily one to ten, but it was it there w there were improvements, whether it was like a one to three, one to five, you know, whatever it was, it was definitely for volume matched, it was better. Um, but but we're talking about again, even more than that if we're looking at the actual type two diabetes diagnosis. Yeah. I I mean, I feel like it aligns with a lot of his studies that he's done because I mean, I know his group has done some of these
Sprint interval training studies where they're doing less than 10 minutes of exercise per workout. And then you compare that to a forty-five to sixty minutes. It almost kind of lines up with what we're seeing in this study, the one to ten ratio with uh in you know, in some of his actual randomized controlled trials, that one to ten sort of ratio between the sprint interval training and the moderate training too. Um and one of the things though I wanted to mention I I think
I think the signal here for diabetes risk was probably the most drastic, that one to ten ratio of moderate to vigorous. And obviously, you know, exercise is important for it, but I think what's important probably why this signal is showing up in this study is because the movement throughout the day is what I think is so important for glucose control. Yeah, if you do a workout in the morning
And don't do anything the rest of the day, you're gonna be probably pretty insulin sensitive throughout the day. But what really is better is doing, you know, ten, fifteen minute kind of bouts of movement throughout the day if you're really trying to improve your glucose control.
And so I think that's one of the reasons why in this study that objectively measured every single type of physical activity people were doing, the vigorous exercise was shown to be so beneficial because you're if you're just moving more throughout your day. you have better glucose control, you're definitely gonna have better long term outcomes than for
diabetes risk and things like that. You're gonna have lower HBA one C, better insulin sensitivity, lower fasting glucose. Um and so I think that's sort of why that that's showing up here in in the actual outcomes like you said, which
for most people are more important than the biomarker data, probably. Right. Yeah. And I also um just want to add on to that like a couple of things. One, you know, that makes a lot of sense too, by the way, you know, doing the exercise throughout the day and and the fact that matters this
specific study that was published in Nature Communications did pick that up because of the accelerometer data. But I do want to emphasize the the the lactate signaling here and just knowing that as you are getting that vigorous intensity exercise. that is really like it's not just a muscle contractions, glucose in thing. It's a glute for transporter where you're you are for a longer period of time throughout the day and perhaps even the next day somewhat, but definitely for twenty four hours.
it's the those transporters are active and ready. And so I think that's another really just powerful Effect of, you know, the intensity of exercise on top of the fact that we also know that when you engage in more vigorous intensity exercise,
¶ Mitochondrial biogenesis-why intensity is essential
the lactate also signals to another protein called PGC one alpha, which is responsible for the growth of new mitochondria. This is mitochondrial biogenesis. So this is happening in your muscle cells as well. And this is improving metabolism of not just glucose, but you know, other substrates like fatty acids as well.
And so I think there's this long term effect. And if we're looking at, you know, type two diabetes, we're not just looking at biomarkers. Like you I don't know you necessarily would pick that up on biomarker data if you're just looking at blood glucose regulation or insulin sensitivity. But if you're looking over the course of like, you know, several years and you have m better mitochondria, more healthy mitochondria on top of like, you know, improved
glucose regulation through the glute transporters and all that, um, you probably are also going to just see a healthier metabolic profile, right? I mean that's Something else to to for sure. I think unless you were measuring like with a continuous glucose monitor, you really wouldn't measure that. You know, I think sometimes he's fasting.
I don't know how much stock to put in, say, like a fasting biomarker of your fasting blood glucose taken one time per year, like every single year. Like what does that really mean? But now that we have access to C GMs and technology like that, I think you could actually you would actually see it in that data. Right. Um
Especially well, you know, we and we don't really have any good biomarkers for mitochondrial health. Like that's like not it's it hasn't been translated to the to the clinic yet. It's something that researchers can and do. In fact, um looking at the talking about some of the studies that Marty Gabbala cited on the podcast previously for volume matched exercise.
High intensity novel training is better at increasing mitochondrial biogenesis than moderate intensity exercise. Again, it has to do with that. stronger stimulus causing the adaptation when you're forcing your muscles to work so hard that they can't produce all the energy they need from just using their mitochondria alone. They ha it forces them to also use just glucose without mitochondria.
Your your your muscles like, dude, I need more mitochondria. This isn't working, right? So that's an adaptation that's happening and it makes sense. And so I know a lot of people for for I've I've at least gotten a lot of questions from people talking about but I thought zone two training was the best for mitochondria and You know, it depo depends on what we're talking about here. We're talking about mitochondrial biogenesis.
you know, great, zone two does inc increase mitochondrial biogenesis. But, you know, if you start to go a little more vigorous, you actually can get a stronger stimulus. And I know that's um
what we're talking about here, vigorous includes zone two, but I'm just saying generally speaking, um it the more aga it just gets back to this whole idea, right? The more intense the stimulus, the greater the ad adaptation to a degree. Obviously you don't want to go to the age Complete extreme where it's like n all you do is work out.
I'm not gonna say that's all you do, but you definitely work out a lot. Sometimes it seems like that. My wife will tell you maybe. Sometimes it seems like that. But yeah, I regarding the I the biomarkers of mitochondrial function, I know that's not what we're like talking about, but it is interesting to
¶ Can you directly measure mitochondrial health?
you know, hopefully some day we have like a an ability to look at, you know, a non invasive test of, say, your mitochondria. I think the best thing right now, which a lot of p which people have access to, but it's kind of Burdensome is to test your lactate during exercise or your resting lactate. If your resting lactate is elevated or if you do low intensity exercise and your lactate levels are spiking up.
your mitochondria probably are not g uh good. That's like a poor way to describe it. But either poor mitochondrial function, not enough mitochondria. I th so I think like a lactate test during exercise is probably the best way. Like currently non invasively without having a muscle biopsy done but Sooner or later, hopefully we have some sort of biomarker to say
You know, what do your mitochondria look like? Yeah, no, and people yeah, people can buy these lactate meters and i th it's a little finger prick test you can do and I've done it several times and it's it's kind of fun to do as well. So I encourage people to try that out. I think another sort of surrogate marker in my mind is also looking at oxidative stress markers because when your mitochondria are not functioning well, if they're damaged, if they're unhealthy. They will
produce more reactive auction species. They are the major generator of reactive auction species. And so, you know, that's another sort of surrogate marker, I would say, as well. But yeah, it's kind of annoying that we don't have a direct marker of mitochondrial function. And I know people are working on that. But, you know, everything takes a long time to to make its way to to our our homes. Yeah, for sure. Unless you want to go get one of these huge like
health panels done that cost probably several thousand dollars to do. But I I I mean honestly, like maybe maybe it doesn't matter too much, but it would be interesting for people to know, you know. Does this protocol actually increase your mitochondria or not? No. I mean the biohackers out there wanna know, right? They do for sure. And we were talking about this urolithin A compound on on the drive up here in
and how that's important for mitochondrial health. And we're actually gonna cover it in in the newsletter. But um I'm I'm taking it right now and I'm like, it's all, it's all What am I measuring to know if it's really doing anything, right? I guess BO two max would be something to measure, but you have to have good baselines and I don't have all that, so you know. Yeah.
Sometimes it's all uh a gu I guess a exercise in faith, maybe. Hoping this boosts my mitochondria. At least I think it does. So Okay. Well I wanna circle back to sheer stress because
¶ Does vigorous exercise kill circulating tumor cells?
Um, that also plays a role in some of the mechanisms behind the reduction in cancer mortality as well. And that's something that uh Dr. Carrie Kernier talked about on the podcast. So you know, the the reductions in Cancer related mortality weren't as high as, you know, the type two diabetes risk reduction, but they're still significant enough, right? You're talking three point five.
You for every one minute of vigorous activity you have to spend three point five minutes of, you know, moderate intensity activity, almost four minutes, right? You can if you if you round up, I I would say it's almost four minutes.
Um, why is that the case? Well, there's a probably a lot of again mechanisms, but one that I think that's super interesting is that sheer stress that's improving your endothelial function, that's improving, you know, the function of your arteries and in your blood vessels.
It's also playing a role in killing cancer cells. And you might go, What are you talking about? So when people when people have a primary tumor, the cancer cells that make up that primary tumor don't all necessarily stay at that site of the pr of the tumor, right? So what happens is oftentimes you have these cancer cells that'll escape the primary site either through the lymphatic system, they get into circulation. And when they're in circulation, they're called circulating tumor cells.
And those circulating tumor cells are not like your normal blood cells. They're not like your normal white blood cells or red blood cells in your in your circulation. They are all kinds of messed up. They have tons of different mutations. Your body is ready for them to die. Like they are ready to die. They are primed to die. And the only reason why these cells are not dying is because they have found a way to increase
all of their proteins that are basically stopping them from dying. And it's like a balancing. There's like these proteins inside your body that promote death and there's these other ones that like stop death. And it's really just a balance. So like when the balance goes into ro promoting death, the cell dies. If you've got that anti-death, so they're called anti apoptotic proteins, if they're higher, like even if they're like supposed to die.
As long as that signal is saying no, don't die, they won't die, even though they're all kinds of messed up, right? And so cancer cells are that's that's kind of why, you know, chemotherapy, radiation, these things that are very they're damaging, right? It's a it's a major stress on all cells. It's a death signal. it's why it's you know it does effectively kill cancer cells is because they're they already have so much of that pro death s signal there.
there's just a little bit of the anti apoptotic signal and they're just waiting to raise above it. And so that's what those things do, chemo and, you know, and so on. So, um unfortunately they also kill normal cells as well because it's a very strong death signal.
Um, when it comes to the circulating tumor cells, they're ready to die. And I know I went on a tangent. I'm sorry, I studied cancer cancer in my gr in graduate school. Um They're they have these mechanosensors on their cell surface, and and so they're very sensitive to mechanical forces and movement. And that is something that can act as a death signal. So if you think about the shearing forces, right? Shearing forces of blood flow.
that is friction against these cancer cells that again are responding in a way where that it's it's a it's a negative stress to them and they die. And that's something that's been shown in vitro. Um it's it's something that if you look at people that have circulating tumor cells, uh if they engage in physical activity, they're less likely to have cancer recurrence or cancer metastasizing.
So the circulating tumor cells, why why is it so dangerous to have them in circulation? Well, for one, um, let's say you were you already had cancer and you were treated with cancer. successfully, quote unquote. Let's say you're you you know, you got chemo radiation, maybe surgery, maybe all of the all three of them, right? And and now you're tumor free, whatever. Um, so you're in remission. But the problem is that
currently in the clinic we're not looking we're not doing single cell analysis and looking at every single cell and every single organ to make sure there's not even one cancer cell left, right? Like we're just saying, Oh, the tumor. We don't see the tumor, therefore we, you know The cancer's gone. what happens is these single cells, they do escape. And if they get into circulation, they'll maybe go some maybe they'll travel to another organ like the liver or something.
And um it might take a couple of decades, three, four decades, and all of a sudden you're having symptoms and you're like, what? I have liver cancer now, right? So cancer recurrence happens, maybe it's in the even in the same it's the same organ.
uh whatever. Um, the qu the the point here is that the circulating tumor cells are really they play a role in cancer metastasis to other organs and they play a role in cancer recurrence and people that have already had cancer and perhaps been treated successfully with that cancer. So
Um, the shearing forces are really important here because they do kill the circulating tumor cells. That is associated with improved outcomes either in cancer recurrence and mortality, and that is reflective in what this study here is showing.
um, that vigorous intensity physical activity is associated with a lower uh cancer mortality. And I know that was a very long winded way of uh explaining it, but it is a a little bit of a passion of mine. So Um, I think I think there's other mechanisms at play, but I do like the shearing forces one because Uh you know, it's something that people don't think about, but it is I think once you once you hear it and you think about it, you're like, Oh, that makes sense.
It makes sense. It makes sense to me. I mean, I've heard you explain it, you know, multiple times and even the studies that, you know, Carrie Crunier was involved in and that we kind of researched and you guys talked about on your podcast, it's like
Exercise directly kills it, kills the circulating tumor cells, which I think is um interesting. Oh, I was wondering, you know, whether you think the stronger sort of risk reduction maybe from ac exercise in this study could have been due to just the fact that
You know, cancer does have obviously a genetic and kind of environmental component, so maybe that's why we're seeing that one to it was like four maybe ratio instead of the one to ten or one to eight ratio with cardiovascular disease or can or uh diabetes risk that we saw in this study. Yeah. I mean there's obviously cancer, there's so many things that are involved. And I think you're gonna talk a little bit about some of the hormonal and other cellular responses, which
I mean hormonal response like there's there's a lot of things going on with with cancer, but yeah, there there is a genetic component and there's other environmental factors that play a role as well. Yeah. So then just moving on to I guess we had two more mechanisms sort of um the hormonal cellular responses as you mentioned. I think you kind of covered that pretty pretty well. But obviously with these vigorous intensity activities you get
¶ Why vigorous intensity triggers beneficial hormone changes
More adrenaline, more cortisol, more growth hormone. Anything that you get with low intensity activity is sort of just heightened with high intensity activity. Hence the idea that you don't want to overdo high intensity exercise because you get too much cortisol, too much, you know, adrenaline, and if you don't let that Recover and then go back to normal and do it again. It could lead to, you know, burnout or overtraining, however, we we want to define it. But um, you just get sort of this.
more better hormonal milieu, I guess, during um high intensity and vigorous exercise that you get during low intensity exercise, which I think explains probably the reduction in all of these, you know, different outcomes. Diabetes, cancer, um cardiovascular disease.
¶ Can vigorous activity protect older adults from falls?
But the last thing I think that is important with vigorous exercise for especially when we're talking in the context of older adults is this muscle fiber recruitment.
So most people will be aware that muscle fibers are categorized into different types. We have type one, which are referred to as slow twitch muscle fibers. Then we have type two. There are subsets of type two and maybe don't need to go into the details of those, but we have to A, to B, and then to X, they kind of go on this spectrum from very fast.
oxidative glycolytic to sort of these this mix between aerobic and glycolytic fibers, but we'll just put them in these buckets of type one and type two for now. Type two are fast twitch, type one or slow twitch fibers. During low intensity activity we're gonna activate those low or those slow twitch fibers. So if you're
leisurely walking, you're doing the dishes, just to use some of the examples from from this study. You're gonna be activating those low intensity, those type one fibers. Even if you're doing something like endurance exercise for the most part. probably type one fibers are gonna be activated. And then as you increase the intensity of exercise, increase the force of, you know, or the weight of something that you're moving if you're lifting weights.
that you're going to progressively activate more type one fibers and then move on to the type two fibers eventually. And so in the context of this study, I think, you know, why are we seeing this outsized impact of l uh vigorous movement throughout the day. Well, if you're doing more vigorous movement, you're activating these type two fibers more um and you're giving them more of a stimulus. And type two fibers are the type of fibers that will atrophy first.
And lose strength first with with age. So you lose type f two fibers first, and then we move down to losing those type one or weakening of type one fibers. And so the more vigorous exercise you're engaging in just even if it's just chores, even if it's
If you pick up a box, you're engaging type two fibers, depending on how heavy that box is, obviously. If you're carrying your kid, you might be engaging type two fibers. Um, so just doing this more vigorous activity throughout the day and then obviously engaging in
high intensity exercise and vigorous exercise, you're gonna engage more of those type two fibers. And those play, I think, a role uh important role in a few things. So for diabetes, going back to what you talked about, more glucose. So if you can activate those type two fibers,
You're gonna you'd be able to use more glucose, better your insulin sensitivity, lower your fasting, blood glucose. Um, but with all-cause mortality, too, it's kind of interesting because You know, I know that one of the people who talks about this most is like Peter Tia, but you know, the leading cause of death or one of the leading causes of death among older adults is you fall, you break a hip, you're in bed for several weeks, you never recover from that.
Well, what type two fibers are important for, these are these are the power fibers. These are what if you trip over something and you need to catch yourself or you need to just prevent yourself from falling, the type two fibers are what are going to be responsible for that. And if you have more power producing fibers, stronger type two fibers, You're gonna be less likely to fall, hence, you're gonna be less likely to experience these disuse atrophy or these um catabolic crises as you've
referred to it before. And so I think that when you look at a cohort of adults like this one, over 70,000 people who inevitably are probably experiencing falls at older ages. And that could be one of the reasons contributing to their all-cause mortality rate. Um that good you know, they're doing more vigorous vigorous activity, they're less likely to fall. They probably have a lower um
chance of experiencing all cause mortality. And so just trying to tie that into maybe a few of the different outcomes in this study, diabetes and all cause mortality. I think that's why we see the benefit there is because If you're doing more of this low and or this high intensity activity throughout the day, you're engaging more type two fibers. And we got to protect those. Um, so the ones that go first.
power and strength decline with age and that's a result of the loss of type two fibers primarily. Really good points, Brady. I I hundred percent agree. I mean I think that's probably really tied into the the reduction in all cause mortality.
And it's also, you know, one of the big reasons why I I I engage in CrossFit. I do a cross a lot of CrossFit types of training because I'm getting I'm getting the functional, I'm getting the explosive power, I'm getting the strength, you know, I'm I'm I'm doing I'm doing all that type of um resistance training, but it's mixed in with aerobic and these high intensity vigorous
you know, types of workouts. And so you're really just getting it all. And and for me it's it's a very time efficient, great way to get the whole shebang, right? It's not just the the cardiorespiratory um improvements, but also the effects on the muscle improvements and muscle health and strength as well. Um so the other thing I that I wanted to mention with respect to the adaptations was inflammation, right? I mean so the more intense the the exercise stimulus
¶ Does vigorous exercise combat inflammation?
you're in you're actually generating inflammatory compounds. IL six being like the big one and and that IL six is is actually um signals to, you know, have this anti inflammatory response. So it's funny if you look at the curves, you'll see like a timing effect where it's like IL six peak.
And then like it shifts like I don't remember how much later it is, maybe an hour or so you start to see IL 10, which is an anti-inflammatory cytokine. And I'm not talking about in this study, I'm talking about other studies that have looked at inflammatory biomarkers.
But you'll see this strong anti-inflammatory response. And this is part of that um, you know, something I've talked about before in the podcast for several years is this hormetic response where you're in s you're engaging in this type of
stressful activity, which in this case we're talking about physical activity, and the more vigorous it is, the more stressful it is. And that is a stress on the body. And that does cause inflammation. It does cause oxid oxidative stress. It's causing it's a stress on the body. But
your body is able to adapt to that. And the adaptations is really what we're going for, right? And so the stronger you're getting this inflammatory response, you're getting that anti-inflammatory response that then lasts.
Right, it's like it's not just like countering the little bit of inflammation that you generated during your workout, it lasts throughout the day. And so, like, as you experience other stressful things in life, whether it's you ate your you know, ate a bag of chips or whatever, I mean, obviously you're gonna have the calorie intake but
you know, the inflammation generated, you're gonna deal with it just a little bit better than if you hadn't have been physically active, right? And so the infl inflammation and the anti-inflammatory resp adaptation that's that's responding to that inflammation is also important because inflammation is a a driver of many chronic diseases, including cardiovascular disease, including cancer.
type two diabetes uh you know, it plays a role in everything, brain aging. And we didn't get into that, but I do feel like this is a good time
¶ Is high-intensity training the key to a younger brain?
to just mention it because we're talking about mechanisms and I've mentioned, you know, the lactate signaling molecule. We know that lactate generated from exercise, particularly as you get into that vigorous type of exercise, that it does get into the brain. There's actually human studies showing that it gets into the brain, and we know it's a signalling molecule for brain drive, neurotrophic factor, a very important growth factor for
Brain health, to grow new neurons, to you know, improve the neuroplasticity of the brain, plays a role in brain aging. So it's it it's not it it ju it just goes everywhere, right? It's not just the the outcomes we're looking at, but also brain I think brain health, I wish that would've been looked at like Alzheimer's disease, right? Like that would have been another really
I really wish they would have put that on there. I I think and I don't know if we've covered it, but I'm sure that there are studies out there because the UK Biobank is so huge and they've published
hundreds of studies at this point, but I'm pretty positive and I can't cite a study off the top of my head, but I know there are studies linking some of the same UK Biobank physical activity data to slower brain aging. And what's cool about the UK Biobank is they literally have measures of not just Alzheimer's risk but physical atrophying of these different brain areas and so
Yeah, again, I don't have a study, but I know that they've published studies from the UK Biobank showing probably dose responses with moderate and vigorous exercise and physical aging of the brain and then lower risks of dementia, Alzheimer's, you name it. I mean it You know, it's pretty uh inevitable that you're gonna see that risk reduction there. Right. It's it's pretty clear again, like if you can do that vigorous intensity activity, you're gonna get
¶ Is vigorous exercise more powerful than we realized?
you're gonna get more bang for your buck. It's gonna be worth so much more. than we previously thought. It's not just two times as good. I mean it's it's much more than that. It's four times as good. It's eight times as good. It's ten times as good, right? Depending on the outcome we're looking at. It's it's just so much better than we thought. Yeah. And I think They I think d us discussing the mechanisms, you know, while I think it's super important because it the mechanisms explain why
vigorous exercise is more beneficial for health outcomes than we thought with that two to one ratio. And that's why it's has such this outsized benefit because it's it's sending this louder signal to the body, regardless of what you look at. You look at
Cancer, you look at blood glucose, you look at um the cardiovascular adaptations. The overall signal is just louder and it's not just a matter of oh, you burn twice as many calories, so it's twice as good for your health. No, you're This you can't really quantify it, it's an exponentially better increase for X outcome. that you're looking at this physiological mechanism, it's an exponential increase when you up that intensity and so
I think it's important for people to know what mechanisms are responsible. And then knowing that you can see, well, this is obviously why vigorous exercise is is better or vigorous physical activity rather to use the correct phrase um compared to lighter and moderate intensities.
B Brady, I totally agree. And I think that, you know, obviously like for people that are focused on weight loss, like great, two to one ratio, you know, that's that's perfect for you to consider as well as counting your calories or, you know, figuring out how you know how what you're consuming'cause that that's all obviously an important factor for weight loss, but like we're not talking about weight loss here.
we're talking about reducing our risk for, you know, cardiovascular disease and cancer and ty diabetes. And so it is really important to realize that two to one ratio is just out the door. It's out the door.
And and and we didn't talk about all the mechanisms. I mean, we could sp we could spend like five hours just talking about mechanisms and people will be so angry with me. But like immune related responses. I mean, there's so many other things going on. When you exercise there's like five hundred different molecules changing and
¶ Can the benefits of vigorous exercise fit into a pill?
uh you know, different physiological processes happening. I mean you just you that's why you can't pill up exercise. Yep. Like you just can't. It w it won't ever happen. Yes, I said that, it won't ever happen. Someone's gonna come out with an exercise pill and it's gonna totally not be an exercise pill.
I mean it's gonna be one aspect of it, but like you just there's so many different physiological adaptations that are occurring in different organs and you're just it's it's it's really a panacea. It really is. Yeah. Everybody wants that. Say, oh well PG C one alpha, that's like the exercise pill. It's like, well that's just that's just one part of it. Small part. It's one small part. I know. I mean, there's so many things to focus on. I mean, that's why
I I've really like in the past few years, exercise has been like the focus of not only this this podcast, but just in my personal life. Like I've it's a priority. Like No matter what. I get exercise and it could just be ten minutes. It could be ten minutes of vigorous intensity exercise.
And now after this study, I'm even more excited about my ten minute workouts because there I'm really getting more than I even thought I was. Totally. So um let's talk about some of these, you know, sort of short bursts of physical activity.
¶ How small doses of intensity might extend your lifespan
Starting with uh the vigorous intermittent lifestyle activity studies. These are the Vilpa studies. Um, we've talked about these before on the podcast. Marty Kabbalah came on, he's been a co author on some of these papers. Um talking about this concept where, you know, researchers are using these accelerometers. They are measuring people's everyday movement in these short bursts that they don't necessarily consider if you sit down and ask them about their
physical activity for the past week, right? So these short bursts of, you know, carrying groceries up three flights of stairs or I raced to the get to catch my, you know, subway because I didn't want to miss it. Or yeah, I was playing with my new four month old puppy puppy like I do twice a day or whatever. Like these are short bursts of
your physical activity where you're getting your heart rate up in everyday situations. It's not necessarily a structured exercise snack, which, you know, also is another way of doing that, but it's again, it's the stuff that people are just sort of everyday doing as part of their lives. And um There's just I think mounting evidence now there's beneficial outcomes with these types of short bursts of physical activity that we just can't ignore. We just can't ignore it anymore. And I've probably
cited this one nature study like a million times so I I for forgive me for the people that have heard me say this a million times. I think you're responsible probably for the I don't know however many like downloads of that article on their website they have. Yeah, it's pretty popular it's pretty popular um study. So
People these sh these short vilpas can be anywhere between one minute to three minutes in length. You know, they're they're they're not super long. It's certainly not ten minute on the Peloton, right? One to three minutes. And they're done multiple times a day, right? Because it's like just your everyday life is what we're talking about.
And so I one of the most profound findings of the study I like to talk about, one of the one of the Velpa studies, is um on the upper end of that. So people that are doing like the three minutes. Short bursts, and they're doing that three times a day. So a total of almost 10 minutes a day, right? It's like nine minutes a day. They're getting this.
Physical activity. And those individuals have a 50% reduction in cardiovascular related mortality, 40% reduction in all-cause mortality, 40% reduction in cancer-related mortality. robust. I mean, especially if you start looking at some of these other studies where people are engaging in their structured physical activity based on their
memories and their their brain's ability to recall in the last week what they've d done, it's even more robust than some of that. And and the reason I like that and and I know that you feel the same is that because it's actually capturing what's really going on. It's capturing the real movement here. And um So these studies, these these vis vigorous intensity lifestyle studies
There's multiple studies of them. There was one also that was recently done in women and looking at like some of their um their cardiovascular disease risk and it was is pretty profound, I think. So some of the some of the risks in the women um let's see if I can find that study. Yeah, so it's a 45% lower risk of major cardiovascular events.
And women doing Vilpa, and they were just doing 3.4 minutes per day. So this is much less than nine minutes, as I just discussed. So they were doing 3.4 minutes of Philpas per day and that's a forty-five percent lower risk of major cardiovascular events, a sixty-seven percent lower risk of heart failure compared to the women that weren't doing any of these physical activity bursts throughout the day. And if you think about that, that's not a lot of time.
And you know, we all have aging parents, like Like j just imagine if we could get them to do four minutes a day of some kind of vigorous intensity activity. Now maybe your parents are retired and they're not necessarily trying to get to the subway or the train or whatever. it's gonna be more of a structured exercise snack and I'll let you kind of talk about some of that. But like you we c you know, they can engage in jumping jacks or maybe chair squats or
people that are, you know, maybe not older, they can do burpees or, you know, you know, bodyweight squats or, you know, push-ups, like a combination of all these things. Um, and we're talking about really having a pretty outsized effect on reducing some of these negative health outcomes.
¶ Do short bursts of vigorous movement match full workouts?
Um What was so interesting is there's another study that really it was a Vilpa study. When I say Vilpa, again, people I'm talking about vigorous intermittent lifestyle physical activity. This is not something this is this isn't going to the gym and doing Peloton. This is just your movement throughout the day.
um being m as measured by with an accelerometer, um, i the benefits were equivalent to people that were doing structured exercise, right? So there was like sixty two thousand people um who actually did exercise and they compared that to people that were doing Vilpa and it was crazy, but the same outcomes in terms of risk reduction, it was comparable. And I love that. I love it so much because it really
it really shows that your body doesn't care if it's structured exercise or not. It just wants the movement. It just wants the movement. So Super important to to to point out. Yeah. And a lot of those studies, most of those studies too, were in non exercisers. So they were in people who reported or said that, you know, I don't regularly engage in
structured exercise and I just d then they just did Vilpa. So the non exercisers benefited that. And like you said, similar to people who exercise, which is kind of a crazy finding. Um and it's interesting'cause reading all these studies and in the past few years is is something that I definitely had changed my mind on in that I used to think, oh, if you're not going to the gym for 30 to 40 minutes.
And obviously, it depends on the goal you're training for. If you're training for a competition or something, you need to do a dedicated training session. But if it's kind of just for health outcomes, It used to be, Oh, you fifteen minutes at least and if you're not doing thirty to forty five, it's kind of a waste of time, but
Now it just seems that even if it's less than 10 minutes, and they even removed it from the physical activity guidelines. The guidelines used to say 75 to 150 minutes of vigorous or 150 to 300 minutes of moderate. performed in bouts of ten minutes or longer. And they actually nixed that part from the guidelines. It's not even in there anymore. So they no longer acknowledge that you need to do it in ten minutes or more. You can do it in whatever
length bout you want to, obviously probably a minute maybe minimum, but to four minutes is great. And so it's something that I've changed my mind on personally in regards to if I'm talking to people about how they should do activity, it's no longer it needs to be 30 minutes or more.
Just like accumulate, accumulate, accumulate as much as you can. Like you said, your body it really doesn't care. It's not your body doesn't have a watch or a clock where it's measuring your physical activity. It kind of just knows like how much you're doing over the day and the stimulus that it's that it's getting. For sure. Yeah. And I was talking to someone yesterday about this who, you know, is interested in health and wants to be healthy but like hates exercise. And their response was
Thank God. Like the running with my dog that I'll like do in burst or like with my kid, like counts. And I think that's important because it's not that we're disincentivizing people to not engage in structured exercise. We're rewarding people who do this unstructured exercise and we're saying, keep doing it. It matters. It adds up.
And I'm totally with you on it's th you know, these these Vilpa studies, these vigorous intermittent lifestyle physical activity studies have really changed my mind as well. I was probably less of a snob than you because you're an endurance athlete, but I was somewhat of a snob thinking Like, no, you have to like you have to have structured time and like, you know, get your heart right up and really like dedicate time to this.
And and these studies, even at first I was kinda like, Well, how is it, you know, okay, let's say ten ten minutes a day, you're doing that every day. So that's what, seventy minutes? It was even less than that, it was nine minutes. So it was even less, right? So like you're like Okay, around seventy minutes a week, I'm getting a fifty percent reduction in in cardiovascular blade mortality. But the guidelines say seventy-five minutes a week is the minimum.
Now I get it. Like this study is saying, no, we underestimated what the vigorous, you know, activity really is giving you in terms of benefit for these health outcomes, right? Because of the way everything was calculated. It wasn't based on health outcome data and it wasn't based on, you know, actual empirical data measuring, you know, how vigorous, you know, your exercise is and how that correlates to health outcomes. And so
This is all it's so important. It's unbelievably important. And I'm so excited about this paper. Yeah. And I mean it makes total sense too, because if you look at
¶ Why your wearable might undervalue short vigorous bouts
Th these are separate studies, but if you look at the Vilpa studies, okay, so say do you're doing four minutes a day of Vilpa, well, then what is that eat that's equivalent to maybe for cardiovascular disease, that's equivalent to forty-five minutes a day of moderate activity or
um, you know, a hundred maybe two hundred minutes of low intensity physical activity. So if you use the equivalence ratios that we were just talking about and apply it to the Vilpa studies, that also kind of adds up with like the risk reduction. So
That's kind of exciting to me. Also, you see this convergence. Some of it is coming from the same biobank data, which is interesting and it's the same group, but you see that convergence there of, okay, well, this story is actually like making sense now that we
This or at least like the data are are lining up with one another, which is exciting to see. I love I love how you put that because, you know, like even just this morning I I spent you know, sometimes I'll spend ten minutes like just sprinting around with my puppy, like playing chase or tag.
and um or it'll be like a five minute bow and another five minute bout. And now I have to think about that in terms of, okay, if that's if I'm looking at, you know, cardiovascular related mortality, let's multiply that by eight because that's how much moderate intensity you know, physical activity that's equivalent to. And it really does incentivize you to find ways to like engage in this sort of like everyday life like intermittent burst of physical activity.
where you're you're like, I'm gonna find a way to like move around like hit like run around and play soccer with my kid or whatever, you know, sport with your with your kid or your your puppy or your dog or I mean it's just I I just love it. I think it really helps um, reinforce the importance of this like movement throughout the day, right? I mean, this is how humans used to be too, right? It's a more natural way. I mean, exercise is inherently sort of this weird kind of thing. I mean
the fact that you're taking time out of your day to go move is kind of weird. It's not how we would have evolved. You know, we just evolved with like lots of movement throughout the day, low intensity and then sometimes it would be high intensity. So it's like The fact that I woke up this morning at
6 30 and went and just ran 15 miles and then came back to my hotel. It's like it's weird. That's not what we were like designed to do, but you know, obviously it's kind of in fun to do that because you're training for stuff. But yeah, I think we were more designed for just this. different type of activity throughout the day and Vilpit was like would be inherently a part of that. Right. I mean we've created this problem.
of being sedentary, right? Because of the way we work. Right. Yeah. And now we have to like find a solution to that problem we've created. And that solution is now we have to like designate time, make it like a thing, you know, and so yeah, and then it becomes like this work. It's like, oh, and it's some people in their mind they're like, Oh, I have to like take time to do this whereas like if they were to just to
¶ Can planned micro-workouts replace traditional gym sessions?
you know, do some of these structured exercise snacks, right? Like, you know, some examples would be again, like you could just do some jumping jacks or I don't know if you want to get into any of those but Yeah, we can talk about some of the exercise snack stuff. Um I think Before I mean a lot of people have heard exercise snacks'cause you've talked about it before, but I think
What makes them different from Vilpa is that exercise snacks and some people don't like the name. I've posted about studies on exercise snacks on social media and people don't like it. I don't know if it's because it has this connotation with food, but I like the idea of calling them like micro workouts or um maybe like micro dosing exercise or something. But
The difference between exercise snacks and Vilpa is that snacks are planned. So you kind of set out time to do them. They're still short, but it's say An example of so you gave some examples of Vilpa. It's oh if you're commuting to work, you know, you're gonna run up the stairs, maybe with your suitcase if you're traveling or something. So that's a minute of Vilpa or you're gonna sprint to catch the bus. It's not something that you plan, but it's something that you injected intensity into.
With exercise snacks it's different. It's you set aside time and they have more of a protocol aspect to them, so I'm gonna do five thirty second Sprint maybe you have a Peloton at home and it's next to your desk at you know, you're working. You get on the Peloton and you just cycle as hard as you can for
forty five seconds and you get off. You do that five times throughout the day. Maybe, you know, every hour you do it or something. So you don't even really have to change and exercise clothes, but it's structured. You planned on doing it. Or you go out to your home gym and you do
a set of squats or you do a set of uh, you know, uh bench press or something like that. So the exercise snacks are structured, but they're still short and they're sort of just still injected in throughout your day. So you don't have to change, you don't have to go to the gym. You probably don't have to shower after doing them. Um That's kind of the idea behind those.
And examples of that, I mentioned a couple, you know, what would be like a lot of the studies they'll use sprints on a bicycle or something like that. And what's crazy is that I think you can't do the Vilpa, a lot of that comes from the observational studies, but with exercise snack. People like Martin Gabbala, other groups have actually done studies on them, and they've shown improvements at VO2 max of two to three milliliters per kilogram of oxygen with just.
you know, a six to eight weeks maybe of just performing these exercise snacks regularly. And that's similar to what you're gonna get through structured exercise training.
A lot of these people are untrained when they start, so they have a lot of room to improve. And if you're somebody who regularly trains, you might not see that magnitude of an improvement. But I think it goes to show again that you can get these adaptations with exercise snacks if you don't have the time or don't want to make the time to set aside.
30 minutes um a day to say exercise. You can really just get on the rower, get on your Peloton for 30, 45 seconds, do that five to ten times throughout the day. So that's kind of the idea behind exercise snacks. You plan them, you set them out, they have a protocol to them. That's a little makes them a little bit different than Bilfa, but it's still sort of the same philosophy where
You don't have to exercise for 30 to 45 minutes at a time. Yeah. My favorite snacks that I do is are just actually air squats and doing three minutes of air squats. burns. Like you don't have to have any weight. It's like a different kind of Ouch, you know, than like lift like heavy lifting, which I also do. Um, and you know, you just you can again you just like you don't even need any equipment. You just get up and do them. But it's nice to know that it's like, okay, three minutes.
Well, if we're talking about, you know, reducing my cardiovascular disease mortality, you can multiply that by eight'cause that's how much time I just spent doing moderate intensity physical activity. Or let's say you only do one minute. Again, multiply it by eight. It really it really puts things in perspective. I mean, I think
you know, these sort of short bouts of structured exercise snacks or these, you know, vigorous intensity physical activities that we're doing, running with our kids or dogs or whatever, running up the stairs, all these things now I think We've we've talked about them before and all the benefits, you know, but now I think we can even put numbers to them, right? Where we can start to go, oh, I just
you know, this is really like worth eight times the amount of moderate intensity that I really did save time. Dopamine, okay, reinforcement. I'm gonna continue to do that, right? The b the behavior's gonna be repeated. Um It gets past the phrasing of, oh, I only have I only did four minutes of exercise. Well yeah, you only it's only four minutes, but we need to stop thinking in terms of minutes and steps, I think, because it's
Those are like outdated metrics. It's minutes are important, but what is the value of a minute of a minute of different types vigors or different intensities of exercise is different. A minute is not a minute is not a minute. So we need to just I think get past this idea of yeah, it was just like four minutes or it was just Um, you know, uh just we it's just 10,000 steps because what 10,000 steps of how intense, how what was you know, we're going upstairs?
Right. Context is key there. I challenge people, like to what Brady just said, I mean, a minute if you just go for a minute leisure stroll, just walk for one minute and compare that to how you feel after doing just one minute of air squats. Or burpees, if you really like one of like you're gonna see the difference. They're not equivalent. They're not equivalent and you can feel it. You can feel it, right? I mean that in and of itself. And I think that
¶ Why exercise guidelines urgently need updating
brings us to implications for these public health guidelines, which we've been hinting at, you know, I'd say all along. We can also talk about some of the tech in wearable device as well. But I mean, I think The bottom line here, and I don't know what it takes to get updates in these types of guidelines, but
I think they need there there needs to be an update. Like this is something that needs to happen. Um, you know, we have empirical evidence here. We're not just looking at weight loss. It's not all about, you know caloric expenditure, energy expenditure here, right? We're looking at actual health outcomes and we're looking at what it took in terms of like you know, the types of exercise to achieve those risk reductions and those health outcomes. And right now
The seventy five minutes to a hundred and fifty minutes of vigorous intensity activity, you think that's just your that's what you need to do to get, you know, one hundred and fifty minutes to three hundred minutes of moderate intensity activity. That one to two ratio Out the door. Out the door. Would you agree? I mean it's really I I would agree with that as well. And I think if you just look at some of the newer
I mean, I I think clearly, you know, there are people out there in public health who have more experience in public health than me in creating guidelines. I'm obviously probably not qualified to make exercise, you know, guidelines or but if you look at a lot of the data out there, I mean we were talking about this in the drive here. I th they are obviously based in some evidence on health outcomes, but I think that they probably need an update and I think that a lot of the data would show
You need a lot more moderate intensity activity or the dose response of that is much higher than the one hundred and fifty to three minutes, which actually had been increased a little bit. They recently added the three hundred minutes. It used to be just a hundred and fifty. But I think, yeah, based on what we've been talking about today, I mean
They certainly need an update and probably an update where we exclude a lot of these earlier self report studies and just say we have so much d data from wearable devices now. We have big health data. I mean, you know, and we have companies like now Google and Aura and Fitbit. I think you know, Google probably owns Fitbit, but it's just
Everybody has a wearable these days. And the fact that we can't mine some of these larger data sets like the UK Biobank or the NHANES and formulate better guidelines that are based off objective evidence, I think is kind of a disservice probably to public health. Um it maybe it's similar to the food pyramid. I'm not even sure anybody
looks at those guidelines and is like, Okay, I need I'm gonna get hundred seventy five minutes per week of vigorous activity. But I think they need an update and I think that the idea that we're just saying Yes, you know, twice as much moderate if you're, you know, then vigorous. That certainly is um a little bit outdated based on what we've talked about today. And
just other data that's out there. Yeah. I do I do think that I don't know that people look at the food pyramid, but I do know that people ask me all the time about how much exercise is optimal. for m like, you know, aging the best and and and lowering my risk for, you know, disease X, Y, and Z, right? And so I do
There's definitely a lot of people that are interested in health that look at those guidelines. And even people like me who are trying to figure out like what are the guidelines and how do I communicate this information to the public.
I mean I'm I am using those guidelines as well and now I feel like my my my you know, I've I've shifted my understanding of that those guidelines and I have a different sort of take on them where where it's like, okay, well maybe we're really undervaluing the importance of vigorous Physical activity.
And so that needs to be communicated to people, you know, maybe we don't say, Look, this is the new guideline'cause obviously like you said, we don't make the guidelines and there's probably a lot that goes into making these guidelines that we don't quite understand or maybe there isn't, I don't know.
Um, but you know, I think we can at least communicate to people that, hey, look, there's new studies out there now showing that it's not just a one to two ratio. And and and uh in fact, depending on the health outcome we're looking at, that ratio changes.
And you know, and that's that's how biology is. It's not just this big blanket thing, right? I mean it's we always try to make things simplified for everyone, but they're not simplified. Like there's lots of nuance here. And I think that it should be communicated in our public health you know, guidelines that should be that should be communicated to anyone that's interested in improving their health. And I do agree with you. I think
Um we have so much data now on these wearable devices and as I mentioned you know before, um I'm on the health advisory board for Google's Pixel. They did buy Fitbits now Pixel and um I know that they're they do publish a lot, like they're one of the few um groups that have this wearable data that does
academic publications and really are evidence based and so I know they're gonna be probably working on this as well. Um, at least updating some of their with what what what they're doing as well. Um And Woop Woop does a lot too. They I I feel like every
every other week I'm seeing a whoop study usually published in Nature where they they do a lot of interesting stuff with their data too. So it's just, you know, showing that, you know, physical activity and different types of exercise and even like when you perform it at different times of day. I mean I think this kind of going back to the idea of simplicity, the public health guidelines for some people, like they have to be simple. And I think that go that
has informed sort of this, well we're just gonna say hundred and fifty to three hundred minutes or seventy five to one hundred and fifty because it is simple. If you make it too complex, people get confused and they just say, Forget it. Like I'm not even gonna try to do it. So I think from a public health mess messaging perspective it's important to sort of have these blanket ranges of physical activity. But I don't know, imagine a scenario where you have
You know, how much exercise do I need to do? Well, for what? Are you concerned about cardiovascular disease? Then you need you probably should do this much. If you're just concerned about cancer or diabetes, maybe you need to do this much. So we could almost get more granular with the guidelines in a way, but um I think I understand the idea that
public health messaging at some point needs to be you can't turn people off from the idea that, well, this is just too complex. I'm not gonna exercise at all. Um So it would be interesting to have a scenario where you have different guidelines for different outcomes. You know, do you wanna age better? Do you wanna are you trying to be like h super high performer or are you just trying to like
you know, control your blood glucose better. You obviously need a different level of activity for those different I would say if we're gonna simplify the guidelines that we at least have to get rid of the one to two and maybe go with the lowest ratio, which was one to three point five. Right. Like That would be but the question is Are these guidelines based more on the outcome data
that was used for vigorous activity versus moderate, right? And again, going back to the questionnaire data, because it was questionnaire data too, right? Like w we we need that there just there needs to be an update first and foremost. There needs to they need to look at more actual empirical data that are, you know, as as measured by accelerometers. And then from there it's like, okay, are we are we looking at how much how much do we need
either vigorous or moderate and then make the ratio and adjust it there instead of this two t one to two based on energy expenditure. Right. Right. I agree. And it's like we don't even need because we have so much data, I don't even think we need to do use that assumption anymore. We can really say val like what is
What is the range where you get this maximum risk reduction? We have that. And then we can just say, okay, for the guidelines, like let's use that five to thirty-five percent risk reduction and say, For five percent risk reduction you need exam minutes and then up to thirty five, you need that. That's where the dose response is and that's how much activity you need. I think it would give us much probably different numbers than
we currently have. Similar to kind of steps. I mean we do it all the time for steps, I think. with the recommendation of how many steps you need. Needs an update. But definitely needs an update. I mean, I think steps need to go out and it needs to be I agree. It needs to be more like the minutes of of uh either vigorous or moderate, probably mostly vigorous, because that's like the easiest. I mean you could do
you know, four minutes of vigorous activity a day and it'd be actually meaningful, um, at least according to the data with the women reducing the, you know, risk of heart attacks and stuff. So, um But that also reminds me with respect to these guidelines. I know you had mentioned how in like twenty eighteen the guidelines were updated to they removed the the the point that exercise had to be in bouts greater than ten minutes.
So that was at least removed, but I think that we need to go even a step further. And it needs to say you can accumulate these, you know, in bouts of one, even in even as low as one minute. Right. Like it can be accumulation of short bouts of exercise. Like
If people read that, it really does like incentivize them to engage in these like short things where they're again playing with their playing with their puppy or if they're working then they're and they, you know, commute to work. It's like it's it's really incentivizing them to keep doing that and perhaps even speed up the pace a little bit, right? Pick up the pace. Yeah. I I think an explicit statement of
Accumulated in bouts of one minute to w however long you wanna make it. I think that would be a a great addition probably. Yeah. Um and then the fitness trackers and apps. I mean, that's another thing, right? Yeah. I mean, I just think about and again, I'm not, you know I'm not in this sector and I'm not, you know, creating these devices, but I'm just imagining, you know, a scenario where, like, how cool would it be if?
One, your wearable activity trackers kind of and a lot of these do it. I know my aura ring does where it will automatically just kind of track and suggest activities that I do. But you know, if you have a activity tracker, you go and play for your puppy ten minutes during the day, you come back.
We sensed an activity that you just did for ten minutes and you can you know, press a button where it'll log it into your day's activity, and then it will reward you in some kind of like, This was worth, you know. t 10 minutes of vigorous intensity activity for your heart points or whatever you're getting, or maybe you're you get some sort of metabolic point for that activity. I think wearable s devices integrating that type of um technology in there.
for the incentives that dopamine boost like you mentioned would be fantastic. I mean gamifying if if if throughout the day, like, oh, I sprinted to catch catch the bus and my watch logged it and I could look in there and see like what was that, what was that worth regarding the day? I mean, we have so much data and the ability to do that. It would be cool, it would gamify it and I think
In terms of adherence, putting that kind of things in there, some people find that silly. Some people that's what they need in order to
engage in that type of activity. You need that constant, oh my gosh, I just gained like twenty heart points from that Vilpa that I did or from that exercise snack that I did. So I think th one, that's where I see a lot of this being implemented where I think it would be would be super cool and then also just updating, yeah, the the value of the physical activity in these devices where it's It's not just uh oh that activity was more vigorous so I got twice as many points as if I did a moderate.
Let's put these health equivalence ratios, like integrate them into the algorithms. Yeah. A hundred percent. A hundred percent. I mean I think that is that needs to be done um for all the devices and uh you know, the the one to two, it's it it like it's worth so much more than that. Now I'm the kind of person that actually doesn't
I just go off the way I feel. Like I I I work out, I do a workout and I like it's so important for my brain and my mental health and my mood. So that's kind of what I am seeking when I'm doing my, you know, even my short exercise next. I do one minute of like air squats and I feel really good after that. It's just one minute.
I I really do. Um, so that's what I need. But I like you said, some people really and I know people like this who they like love all this like gamified stuff and and I'm like, Okay, that's more power to you. That's great. If that's what it takes
And if that's more rewarding and that's getting the dopamine and it's reinforcing the behavior, um, and a lot of people it does, then we need to do it. It needs to be we need to be reinforcing that behavior because at the end of the day, that's what it's all about, right? which I think gets us into this other conversation of, you know,
¶ Does light activity still offer real benefits?
all out, all intensity or nothing, right? Like, you know, I've definitely gotten some pushback um on social media for being the person that likes to talk about going going hard or or going home, but um I don't necessarily say that but Again, pointed out it doesn't mean that everything you do has to be vigorous. Right? Um and I think Again, we keep going back to the definition of vigorous in this study and the guidelines. Like it just means that you need to do
purposeful stuff throughout the day. It doesn't mean you always need to do hit. You do you do need to do some hit, you know, during the week, maybe a couple of times per week. But um yeah, I think the idea that we're not this isn't to say that low intensity activity is meaningless, but it's just, um Yeah. The the purposeful stuff has an outsized impact on health. Yeah. It it's not you know, it it's not meaningless, but
Boy, it's close. When it comes to like reducing disease, statistically meaningless to be you have to do a lot of it. Right. You really do. You have to do a lot of it. Right. I mean I guess if you are willing to right if If somebody is just like I I'm not going to ever exercise, the only thing I'm going to do is light walking and house tours. Well, okay, that's fine, but you probably need to do, you know, ten hours a week of it and if that's what you wanna do, I guess that that's fine. Um
So yeah. Yeah. Not much meaningless. And I guess like it again, what's your definition of meaningless? You know, is it statistically?'Cause based on this study, it's statistically no risk reduction, but Clearly better than sedentary. So is it is it better than what? I think that's the key question to ask. Yeah. It's better than being sedentary, but it's not better than putting a little more effort into whatever movement you're doing. Right, right. And I also think that like
this vigorous activity isn't necessarily like going all out either, right? So like some of these people, if they like going for their leisure walk, very light walk, they can pick up the pace and do some interval walking. And that is that is something I think a lot of peop like i even people with diseases, you know, and stuff can do. Right. Like that's a very like cause you if you pick up the pace for like 10 seconds even, 20 seconds, right?
Um, you're doing a little bit of interval walking. You're just you're you're just getting you're you're just cranking it up a little bit and then you can continue your light walking. I think that's something that people can experiment with um at home, especially the ones that really just love doing their light walking ten hours a week. Um, you know, so um but that kind of gets it transitions us into this special populations, you know, does
¶ Is vigorous exercise safe for older adults?
Is there is there any population that we have to be concerned about for doing, you know, vigorous intensity? And I do get this question a lot from people, older adults. I'm old, can I do a vigorous type of workout? Again. We're not talking necessarily about just high intensity interval training, although that does include it. We're talk also talking about, you know, maybe cycling or, you know, r running or jogging in a to a point. I think even jogging was considered more vigorous, right?
So, um... like you had pointed out, you know, this study included adults that were up to age seventy nine. So they're definitely older adults, sixty-five and older, right? So older adults did massively benefit from engaging in vigorous intensity uh physical activity. Um I would say that essenti you know, most
Most of people that are older and let's say they've never really done any kind of vigorous intensity activity, it's not that you have to just start it right away. You can work your way up progressively, right? I mean, that's just something to keep in mind. Like it's easy to kind of just work your way up to it.
start out with the interval walking and then like st start in doing a little bit of light jogging in sometimes or or maybe you're just gonna be that person that does these short, you know, one minute chair squats or, you know, something that's th you're gonna accumulate more of the shorter intervals throughout the day as well. Um but it it is important to point out that um
as you're getting older, as you mentioned, you know, the the muscle mask, engaging the type two fibers because they're really going, uh your cardiorespiratory fitness is is decreasing. I mean, all of these things, they're so I would say. Um there's so many reasons why older adults should be trying to engage in some form of vigorous intensity activity and not just following the moderate intensity aspect of the guidelines. Yeah, absolutely. I mean I think that for one, any you know
Obviously, even old or young, if you've never done HIT, high intensity, vigorous exercise, you need to ease yourself into it. You need to kind of, you know, adapt to it before you do it. But There are, I mean, hundreds of studies on let's just use keep using the Norwegian four by four for example, but adults can do that protocol safely, effectively, several times per week and they're not Burning out. They're not, it's not unsustainable. I mean, you hear all these words and it's just like
For the people doing the research and even in graduate school, I was a part of several of these different studies where we used the Norwegian four by four and we were looking at the effect of on endothelial function. And we had people who were sixty-five years old with diabetes coming in and they were doing A couple of these four by four protocols a week, 85% heart rate max. It's like you can do it. I mean, they're it's the only exercise that they're doing. It's a couple times per week and
Even if it's 85% max heart rate, it's it's a fairly low absolute intensity because they're not that in shape. So people can do it and then I think it's important, you know, older adults can do it and they need to do it. Going back to what Ben Levine was talking about. I mean At a certain age, past a certain age, if you don't engage in the vigorous exercise, you're just not going to
adapt, especially with regard to the cardiac, the cardio cardiac adaptations, the cardiovascular system. The heart just needs that extra stimulus and without it, the heart's just gonna continue to stiffen fibrosis as you age. I know we already sort of mentioned that, but um so yeah, not only is it feasible, but it's probably necessary for for older adults to engage in this.
high intensity interval training. I just think that there's this skewed idea when You talk about doing hit that people think it's They're training like Olympic athletes and it's a it's really not. It's Thank you, Brady. Just read the c some of the clinical steps in it's pretty apparent. There there's definitely a group of people I like to push back when I you know, an any time I like post or talk about doing
the Norwegian four by four for some reason. It's it's really I'm not I mean, I'm not talking about like nonstop Norwegian four by four like four times a day, every day you know, five times a a week. I mean, this is like, you know, once or twice a week. You can do it. Like it's not And again, like you said, it's uh the it's a you know, it the relative, you know, heart rate changes, right? So for someone who's not that fit, you know, eighty five percent of their max heart rate is not that.
It's not that hard. Uh I guess it is hard for them, but like right. It might be fifty to a hundred watts or something if they're on a bike, which is a fairly low it's like spin class, something like that. Yeah. Right. Um The other question that often I get has to do with women and like
¶ Are high-intensity workouts detrimental to female hormones?
There's this idea that oh women really can they engage in high intensity interval training, can they really go and again, we're talking a little bit more on the on the high end of vigorous here, right, in in regards to like high intensity interval training. Um, can can women do an hour long high intensity interval training session? Is it is it bad? Are there stress hormones going up? Is it, you know, all those all those things that you hear from influencers on the internet? Um
My take and my read of the literature and my experience. So I do I do high-intensity double training. I do like a CrossFit type of training. three hours a week right now. Currently I'm gonna start doing four. And Two of those hours, it's like the full hour is like it's a pretty pretty intense.
And then two of the other um days where it's an hour each, I'm doing like strength training the first half half, which isn't really getting my heart rate up that much, except for when I'm lifting heavy. Um and then I do like a twenty minute hit at the end. And Hey, I'm everything's g going great for me. I'm not I'm not burning out. I mean, I don't feel like I, you know, I'm like like burning at both ends at all. Um, but let's talk about actual evidence here. I think
Yes, women can engage in high intensity rumble training. Yes, they can do high intensity workouts. I think where this whole thing originated from was were these studies where women were massively reducing their calories and they were doing caloric restriction and engaging in a lot of like high intensity exercise. And that can like cause amenorrhea. It can shift hormones, right? Where you're not ovulating. And that's really like the origin of like some of this like
I don't even know where it's gone. It's gone to places where I'm like people are like, oh, you can't do hit. I'm just like, what are you talking about? Yes, you can do HIT. Like being a female doesn't mean you can't do HIT. Obviously, you have to listen to your body. If you are on your cycle and you're feeling like
I all the time when I'm on my cycle and I'm starting to do a hit, like I tone it down. I tone it down. Like, yeah, I mean, there's obvious things here where you're not gonna perform your best.
you know, depending on what the day is. But that's even for people that are not female, right? I mean, like you have those days too, right, Peggy? Right. I shouldn't do hit all the time either. Men shouldn't do hit all the time. They should listen to their bodies. They should listen, you know, program it strategically into their training cycle.
I I also don't really know where this idea that I think it refers to maybe more so like I don't know, perimetapausal, postmenopausal women should be careful with HIT, but like
S sure. And there are certain, you know, hormonal changes that happen at that time. But again, if we look at what the studies are showing, if you do it in a smart way, that women can benefit just as much as men, there's not really a biological reason I think to think that There would be any detrimental effects as long as you do it smartly and again, like you mentioned, fuel adequately, you know, relative energy deficiency in sport, red S is a thing.
If you're doing more activity than you're fueling your body for and women are um more prone to kind of that underfueling than maybe males are, um, especially kind of in the endurance sports realm. Yeah, you can overdo it, just like anything. But I think to scare women and say, Oh, you shouldn't do hit because it's, you know, gonna be like too much cortisol or something. I mean
The point of it is kinda to increase cortisol and then you recover and do it again. I mean, that's just do it smartly. So yeah, we're not I don't know. I d I'm not sure where it has gone to weird places this idea. Um you will Ah, you know, you shouldn't do you need a women need to train like this a different way and a lot of eviden evidence out there for strength training and endurance training doesn't just really support that idea, I think.
I I you know, it's funny that you mentioned the cortisol'cause that thing you just brought up one of my little pet peeves like You actually like the spikes of the stress hormones. Again, you're having this hormetic response where your body adapts to it. The the problem with cortisol isn't the like little spikes that you're getting from like working out hard. The problem is like the chronic activation of a cortisol like every single day with all the stress.
Um, it's not it's not the you know, the types of exercise stress. Now, are people doing these high intensity workouts like every single day? I mean like you maybe tone it down a little bit. But You know, again, uh listen to your body as long as you're not overdoing it and most people are not overdoing it, okay? Most people are not overdoing it. No, most most people aren't. I think one thing to consider too is like, yes, if you're also a working professional and doing
Also, training on top of that, you know, if you're not a professional athlete whose only job is to train, then you also have to consider life stress. You have a family, you have kids, you have a full-time job. But Again, I think this is You know, that applies to everyone, not just males. Females.
Um so Right. It applies to everyone. And now we know how incredibly efficient HIT workouts are, more than we previously even thought we were underestimating. And so I again all the reasons to do it. Um when it comes to
¶ Safe vigorous exercise options-even with chronic illness
chronic illnesses and stuff, again, it's another thing where you have to like talk to your physician, listen to your body. I mean you know, th there's there's there's ways that you can do these sort of exercise snacks, whether it's the interval walking or a little bit of a step above that and you're doing s maybe some chair squats. I mean, I have my seventy year old mom who isn't the gr in greatest health. Um, you know, she's doing CrossFit two to three times a week for it's a seniors class.
But I mean, she's doing things like chair squats and she's doing you know, she's doing lifts and stuff with very light weights and, you know, there's there's there's a
progressive way to like get this is definitely vigorous exercise for her, for sure. Um, and so I I think that, you know, again, people can even with chronic illness and chronic conditions, you know, definitely talk to your physician, but there's ways that they can engage in particularly these, you know, shorter bursts of exercise as well.
Um and then athletes, right? I mean, that's something that you're the athlete in the room. Yeah. And obviously when it comes to to athletes, you know, the this discussion that we're having I think is totally separate from, you know, athletes are
¶ The 80/20 rule for balancing intensity and recovery
training. They are training towards a goal, they're training for a marathon or a CrossFit competition or something like that. So I think Some of these maybe guidelines on physical activity, you wanna like integrate movement throughout your day, they still apply, but maybe a little bit less because if you're doing dedicated activity, you know, I think most athletes aren't concerned about
getting the recommended physical activity. Most are are getting just, you know, fine physical activity. Regarding hit and vigorous exercise, you know, obviously athletes are gonna need to engage in that. So The conversation is is a little bit different and you do when you are training, you need to be a little bit more deliberate about
Maybe you only do one or two higher intensity exercise sessions per day because you are training every single day or maybe six or seven, you know, six days per week. So um it's a little bit different and I think
There are some studies you can certainly overdo it. You can certainly overdo high intensity infiltraining. There are study interesting study that I read recently. It showed that if you do too much it actually like harms your mitochondria and causes mitochondrial dysfunction. So athletes can certainly overdo that. Um I think the takeaway here, um, if we go back to our study is
athletes, you know, outside of training, you're definitely improving your health and I think good, you know, focus on your long term health. If you're not getting paid to do it, I'm not getting paid to train for a marathon. Um so I still want to run fast, but I also am like concerned about my long term health. And so
Thinking about it that way, you want to make sure to balance it so that you don't harm your long term health in the pursuit of, you know, being healthy. Sometimes you can be kind of counterproductive in that way. So Um, I think balancing it, there's this common thing in athletic circles, the eighty twenty kind of split where, you know, if you're doing
six exercise sessions per week, four of those are easy, two of those are hard. I think that's kind of a good framework, a good heuristic for for people to follow. And I tend to sort of
balance my exercise that way. Like twenty percent of my weekly exercise is maybe harder. Eighty percent is is typically pretty easy in terms of the the distribution. Um but yeah, I think, you know, if if athletes are thinking about how to balance it and if they're concerned about the long term health implications and they also want to reduce their disease risk like everybody else.
I think kind of the same principles here apply. Just don't overdo it. Make sure to integrate HIT a couple of times per week and um balance that with recovery. Yeah. Uh just since since you are the athlete and you mentioned your your your eighty twenty role, how many
¶ Inside Brady's routine-how much vigorous exercise is optimal?
Everything you do would be considered vigorous, by the way, according to this study that we're talking about here today in nature communications. How many hours a week do you spend? being physically active. Now you're not probably not gonna count y when you w run with your dog or you run around with your kid. So we're talking about the structures, not everything, just the
the time that you set aside to do your actual like runs and and hits. So the running and biking stuff during the week probably combined thirteen to fifteen hours of that like a week. I mean, I'm working out seven days per week most days. I'll take a rest day every couple of weeks. So thirteen to fifteen hours of that
couple hours of probably dedicated strength training and then the physical activity stuff I do actually despite being very, you know, just training, I do try to get decent physical activity. So walk. thirty minutes maybe a day, just do a couple of walks also just to kind of break up the
monotony of like sitting in a chair, which I don't think is good even for highly active like athletes. Um, and I'll also do some of the exercise snacks, which is kinda interesting, but my exercise snacks are actually in the form of these resistance training exercise snacks. So I
all in my office I have a pull up bar and the door frame, I have kettlebells and stuff, so every like little bit if I need a break during the day I'll do these I'll do hit, but in the form of resistance exercise to sort of uh build strength if I don't have time to like make it to the gym or something during the week. But yeah, that's kind of what my act activity looks like. So it's a lot of volume.
And you're right that based on this study, it would be categorized as probably vigorous. Um, but obviously a lot of it is light. If you looked at my heart rate, you know it's sixty maybe seventy percent of heart rate max is a lot of that stuff. So it's still at a fairly low heart rate. Even your runs? Yeah. A l a run, you know, I might do a run. If I go pretty easy, my heart rate's gonna be hundred and twenty beats per minute, which is pretty What's easy for you, Brady?
Easy in terms of like speed. No, like seven minutes per mile. You guys hear that? That's easy for Brady. Seven minutes per mile. Oh my goodness. So like sometimes I'll be r on a run with Dan and and we're just I mean, it's like you know, ten minutes a mile. I'm like we're we're talking and like you know it's a it's a fun leisurely yeah it's definitely like we're having a conversation, we're talking and it's like it's time that we get to hang out. Like I go for runs with like friends
And it's like we we we catch up on our run, right? So it's like it's it's a leisurely run. It would be considered, I think, vigorous according to the study. But I'm just sitting here going, I if Br Brady's dude, this is like nothing to him. He runs like for twenty miles at seven minutes a mile. I mean, that's insane. It's insane. Yeah, it takes takes a lot of time to build up to that. But again, you know, if we did a if we did a CrossFit workout that you probably would be able to
I'll do me in that one probably. Smoke you. I'm really I'm really becoming a CrossFitter. Um but you know, your your exercise snack that you that you talked about, I think you just described CrossFit. Like that's what CrossFit is like my workouts.
you know, it's like we're doing these like intense we're doing kettlebell swings and it's not strength training, so it's like a lighter weight, but you are getting your heart rate up and you are you are, you know, doing resistance training, so you are obviously like
working your muscles and and challenging your muscles as well. And it's why I just love it. It's just so efficient. It's time efficient for like everything. Yeah, I think if I think I it's probably the ideal regimen, the high the crossfit and then the High rocks is kind of what everybody is interested in doing now. I think I I want to train for one. I think those are probably the best.
If I had to pick an ideal like this is the ideal workout regimen for life, it's probably one of those, obviously. I mean what I'm doing as not I'm not I'm optimizing for one thing. I love doing endurance training and that's what I'm gonna do. But if I had to, you know, pick what's ideal, certainly those are the best'cause you're getting kind of the best of both worlds. Especially with Hyrux, which has a little bit more
of the running component compared to CrossFit. So I think you're you need to be really aerobically fit and strong to do high rocks. Not to say that you don't with CrossFit, but there's not there's not a lot of running with CrossFit. No. No, there's more like shuttle sprinting and stuff. Yeah. Yeah. Um lastly I want to mention before we kind of just conclude this up.
¶ Can vigorous activity boost kids' brainpower (and grades)?
Uh, children. And, you know, a lot of people are like wondering what what I think I think the take home here with children is Sports are important, right? Like get them involved in some kind of sports, whether it's team sports or individual sports, those things all matter and they're important, not only um just to to their long term health.
But also there's studies showing that Cardiorespiratory fitness, like the the higher the cardiorespiratory fitness is in elementary school children, the better they perform on academic tests.
the better they behave on playgrounds. So it's just improving their overall brain function as well. And that's something that we didn't talk about a lot today. Definitely talked about it previously on the podcast, but brain function is definitely affected. I can't say that enough with more emphasis and it's across the lifespan, young young children all the way to older adults.
physical activity and particularly the vigorous type of vigor f physical activity really does improve, you know, cognitive function in the short term, in the now, but also the way your a brain ages as well. Yeah, absolutely. The the topic of children with training is always tough and I think, you know, everybody has their own individual perspectives on that. But it's like kids naturally will engage in physical activity if you give them time. I think put'em in sports but
Even being the endurance athlete, I'm like I it's gonna be hard for me, but I know I'm going to need to just sort of like refrain from, you know, until they're really participating in organized sports in say elementary school or junior high, like
Yeah, I don't think your kids should probably be, you know, doing structured interval training sessions during the week to try to get them. I find in in anecdotal obviously, but like the kids who were doing that when I was younger, whose parents were pushing them to actually train to run. They're the ones no longer doing it. They just got tired of it and burnt out. Yeah. There is there's also an aspect to that with sports. I mean, when you if you start to push your your child to um be the best.
You know, if they're if they're not good enough and you want them to really be the best on the team. you can push them to the point where they actually don't enjoy it. And like when they're young, it's all about exposure. And it's all about like letting them have fun, letting them not be the best on the team. I mean, some kids are just naturally athletic. Like they
they have to put in less effort, m you know, less deliberate practice time to get to be good. Not not to say that you should ignore deliberate practice. We all know you shouldn't, but you know, some kids like my son is not a naturally athletic you know boy.
But, you know, he has done soccer over the years and he's really put in practice and he loves it now. And he's still not like on like one of the high, high teams. He's like on a development team. But like I like this level because there's not a lot of stress from the parents where it's like
We have to win, we have to win. It's not about it's really not about winning. It's about the kids trying their best, having fun, having sportsmanship. I mean, all those these are all life skills that they're learning. And I know I'm going on a tangent here, sorry. I'm I'm a mom, what can I say? Um
¶ Are we significantly underestimating vigorous exercise benefits?
But that said, I don't know that we need to do a lot of conclusions here. I think that we've really concluded a lot throughout this this episode. Um, the take home for me here honestly is a couple of things. One is that I feel like even myself I was underestimating the power of this vigorous, intense intense physical activity that I get.
you know, throughout the week in terms of reducing my cardiovascular d cardiovascular disease risk, my risk for having a heart attack or a stroke or getting type two diabetes. I mean Um, uh it's really exciting to me to think that I I'm actually getting a lot more benefit than I previously thought. Um, certainly, you know, if you look at the thirty to forty minutes per week of vigorous intensity activity.
Yeah, or sorry, was it thir yeah, it was thirty to forty minutes per week, right? That was associated with like a fifty percent reduction in some of these outcomes. And I'm getting way more than that. So um that's that in and of itself was exciting. That one we're dramatically under underestimating the power of vigorous intensity physical activity. I do think that we all should be aiming for it.
um in some shape or form, um particularly if we're able to. And knowing that the vigorous intensity exercise doesn't necessarily mean the Norwegian four by four, although I still think I I'll still say I think we should be doing that type of hit at least once a week to improve our cardiorespiratory fitness.
But that said, you know, even these like these runs that I'm going on that I have conversations with, that's that's great. That that that counts as more vigorous where I I previously wasn't really counting that it's vigorous.
Um, and then also just knowing about these short bursts of activity, like I'm so excited now. Like I got a new puppy a couple of months ago. She's four months old and like I sprint around with her all the time and I've never been counting that, you know, and that stuff matters. Um that's also very exciting to me as well. Um so
¶ Why chasing steps isn't the answer
You know, for me, I think that those were the the major take homes. I know you probably have your own. Yeah. I mean what you said is it's certainly I think reassuring for a lot of people and they should reframe how they think about the activity throughout their day, like count a count a lot of stuff and do things deliberately that you can either gain like a reward from or know that you're just like benefiting your health. I think it's reassuring to see
That those little short bouts have value, not just from the Vilpa studies, but from this study and just from like everything that we've talked about regarding like the mechanisms. I think my key takeaway was. This study, I mean, it was one of the most interesting studies I've read in a while. And that's kind of why I wrote about it. I wrote about it on my Substack and like we're talking about it today.
It reframed how I think about devices in a way. And I think it should reframe how a lot of people look at their wearable and the data that it is telling you. I'm not to s not this is obvious to to say that you should ignore it, but I think that you should look at the data from your wearable in a different way and really think about what is it telling you? Does it
Are you, you know, when you're looking at how many steps you got during the day, does that really matter? Or like what is the context of those steps? Or, you know, one, what's your goal? And then two, you know, what value are those steps giving you? Because if you're just chasing a number like steps,
It might kind of be meaningless. So should you shift your goal into thinking, you know, let's maybe look at the intensity of my workouts? It'll depend on the device that you have, but just reframe how you look at it and maybe don't just take what it's It's giving you right now until maybe these evolve a little bit, which they hopefully will.
don't take it at face value in terms of, oh, I got enough activity today. You know, look at that. Maybe think about what you and I talked about in the context of the study today and then say, Did I do maybe more or less? Like should I do more? So just don't don't rely on your wearable solely. It should be a tool, but you should also evaluate, you know.
In the context of your health goals, what your activity means and what data you're wearable are giving you. I think that was my biggest takeaway. And it's certainly going to look at reframe maybe how I look at some of the data on my wearable um and look at the guidelines and the recommendations and what they mean for health. I think this just sort of reframes like how we should think about all of this stuff and um it's not just a
This amount of activity is good for everything. We need to really think about it in the context of our overall health and our personal goals. And it can be complicated, but for a lot of people, this is fun. I mean, if people are really interested in optimizing their longevity or whatever health outcome it is.
I think you should really think critically about this stuff. So that was kind of my takeaway from this study. Well certainly the people that are uh listening to this podcast are interested in that. Um how long do you think it takes to take ten thousand steps?
It's actually longer than I think most people think. Um I think if you walk for I think it takes about maybe ninety minutes to two hours. Oh no, probably longer th ninety minutes to two hours to probably get ten thousand steps of like dedicated kind of walking. That's about six to seven, it's about ten K of walking, six to seven thousands or six to seven miles rather. And so that would be
I mean, I guess depending on the pace you're walking, but if you're just doing the late walking, you know, you're really not getting more than a ten or fifteen percent reduction in risk for any of these these disease outcomes. So something to think about people. Um Brady, this has been so fun. I love this new journal club pop journal club um podcast. I think that um I look forward to the next interesting paper that we're gonna cover because I know there's gonna be one.
Um I wanna tell people about your book that I have here VO2 Max Essentials. I mean, if you want to know anything about VO2 Max, Brady's the guy when he has everything in here about you know, explaining what VO2 Max is, the role it plays in aging, what limits it, um, tools and protocols for improving it. I mean, just everything you want to know. So I highly recommend that VO2 Max Essentials, and it's also really cheap. You can find that on Amazon.
You also have a substack. You mentioned that you covered this study in your substack. Maybe you can tell people about your substack. You're on social media, you're very active. You post a lot of really interesting stuff, especially when it comes to exercise related studies. Yeah. Social media, um, people can find me at B underscore Holmer. Um, I'll post it's a mix of stuff from my life and
A lot mostly science. I try to keep it mostly science, but it's a personal account too, so I I will post on there. My substack is physiologically speaking and I publish a weekly newsletter on there. I also just will publish whenever I have maybe an interesting thought or idea, I'll publish like a a thought piece on there. Um, sometimes I post my training too. I know not everybody's interested in that, but right now I'm training for a marathon in December and
I'll post my weekly training log on there. A lot of people find value in there. But um so you can find all that stuff and subscribe. It's free. You can pay either one. Um and yeah, that's kind of where main two channels you can find me, the book. It was, you know, it's probably due for an update, but there's just evergreen stuff in there. If people want to learn the science of U2 Max, it can get pretty nerdy, but again.
If you're listening to this podcast, you're probably interested in mechanisms and protocols and things like that. And you can find that uh all in that book. So I appreciate you uh giving that a little plug. Yeah, my pleasure, Brady. Well, thanks again for joining me. on the podcast and until the next one. Yeah. Thanks for having forward to it. This was great. I think the journal club style will hopefully it's here to stay. I I enjoyed this. Yeah, definitely. Same.
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