4. Fasting

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So we're going to have been fasting for at least the last 10 minutes. It's 12. Yeah , I do intermittent fasting between each meal throughout the day each bite. Yeah. So we're going to get into a different benefits of fasting misconceptions about it, and then also some ways to kind of use it for your training program or just in general in your day to day behavior. Um, so starting off, we'll kind of hit on the biggest buzz word lately.

I guess I would kind of say is , is the idea of intermittent fasting? So kind of give us an idea of what that looks like. Yeah. And I was joking , well , I wasn't joking earlier. I have been fasting for maybe 12 minutes, but I do think there's utility to certain fasting strategies. Um, and you know, they're situational, right? I mean, it's not just this blanket , uh , fasting protocol that's going to fit everyone's needs and be the magic fix. Um, so we'll talk about a few of those.

And you mentioned intermittent fasting, which really as defined in the literature just means like you talked about anytime that you're not eating for a while and then eating for awhile . Um, most people, I feel like in today's kind of a colloquial vernacular , um, just common language would, would consider intermittent fasting to be what we really know is time restricted, feeding, or time restricted eating, which is just limiting the time during the day when you eat.

So rather than saying, you know, I'm just not eating while I'm asleep, extending that to a period of 16 or 18 hours where you don't eat and then, you know, eight hours or so where you do eat. Um, but that if you're using the term intermittent fasting, that can also mean, you know, one day you eat one day, you don't and you alternate , uh , it can mean that, you know, you may be eat during the week, but then take one day during the weekend or 36 hours during the weekend .

So it's really not very descriptive just to say, intermittent fasting. So I think it's, it's more helpful to break it down and use terminology. That's more descriptive of what you're actually doing. And for most people we're talking about a time restricted eating, which is a , a shortened eating window during the day and a longer period of time when you don't eat. Excellent.

And I think it's important to keep the idea of you using a term that describes what you're doing so that you have a better concept of what it is, as opposed to the word intermittent, just kind of a little bit of a vague descriptor. Like you said, it could kind of apply to a lot of different things. Yeah . It's a communication issue. So like, if you're talking to me as your doctor and you just say, Hey, I've been doing intermittent fasting for a while . That doesn't really help me.

There's an assumption there that I understand what protocol you've been using. So it's not the intermittent fasting as good or bad as a term. It's just, it doesn't really tell us what's going on. So like we said, that time window, it can be, you know, alternate days , um, let's really dig into what that looks like. Excellent. So say I'm doing time restricted eating and I'm practicing the way that a lot of others would , um , skipping breakfast.

So I'm trying to maintain, say a 16 hour window when I don't eat throughout the day in an eight hour window when I'm eating . So my feeding window. Yeah. So why am I doing that? That's a good question. Why are you doing that? Um, it can vary. So for some people, it's a way to control caloric intake.

And this has been shown in a number of research papers to be probably the fact that it's easier for people to stick with a decreased amount of time that they eat during the day, as opposed to trying to eat smaller meals or trying to eat less at each meal. Um , so for some people it's just a means of dieting. It means of lowering caloric intake , uh, for S for others, there's a metabolic gains or trying to get.

So we've spoken about in a previous podcast, this idea that if you're constantly fueling with carbohydrate, then there's a constant availability of carbohydrate and your body's just going to burn through carbohydrate because it's there. Um, and we want to at times be very efficient at burning fat.

And so there's a thought that if you engage in a time restricted eating protocol, that there's an extended period of time during the day where there's decreased carbohydrate availability, and you might encourage more fat burning. You also get some concurrent hormonal benefits from that. Uh, every time you eat, it sets off a cascade of , of hormones that tell your body , uh, give multiple signals.

Some of those are good, some are good in certain contexts and maybe not good if you're that context is sitting at your desk all day. Um, so it's a way to kind of modulator some of the input that your body perceives dietarily hormonally environmentally throughout the day. Um, and then there may be a performance , uh, rationale to it as well. That can be athletic performance.

So perhaps you are again trying to do like a fasted fasted cardio type workout , um, where you sleep through the night, not eating you wake up and you're going to do a workout with in a low glycogen state.

Um, so in that, in that framework, this time restricted eating kind of falls into place because unless you're getting up super early to do your workout and then have a normal time for breakfast, which kind of shoots the whole thing in the foot , um, then you're going to be skipping breakfast, doing your workout and having either a mid morning meal or lunch. Uh, so that's almost by default, but it plays into your overall goals anyway.

So say we've been doing the, I threw out 16, eight, and there's a lot of different durations that people will use for their time restrictions . So they'll do a 20 hour fasting window and a four hour feeding window they'll alternate days. What's kind of the thought process between the longer facet windows. Do they have they defined a set line when it's like, Oh, you fit 17 hours. Perfect. That's the right amount of fast, or is this an area that really needs more research?

Well, it needs more research. And quite honestly, it's probably not a question that will ever be definitively answered because it's unlikely that at a given point in time, a switch flips, right. And something happens just all of a sudden metabolically. So we're looking more to gradient. And I tell if you're typical, if your goal is to Institute some sort of time restricted eating, and your typical day involves eating pretty much, you know , 16 hours a day.

Then if you move that to 12 and 12, so you're only eating 12 hours a day, you're moving the needle in the right direction. And you're going to, you know , any of the benefits you're trying to gain from this, you're heading in the right direction. Um, if you can move that further to, you know , 14 and 10 , um, you're probably harvesting more of those benefits. So it's not an on, off switch it's directional.

Uh , but there does, you know, in, in the literature typically you'll see that anything where your facet window is 14 hours or longer, they start to call time restricted eating , um, and some studies or some authors have even suggested that once you get to 21 hours, if you go to 22, it's now the same as like a full, fast a day. Um, and that's getting into the minutia . I don't even know where I fall on that. The whole point is it's really difficult to define.

So I think rather than think of thinking of it in such strict terms, as you know, this many hours counts this many doesn't, it's looking at where you're starting, what your goal is and whether you're moving toward that. I think that's a great notion to keep in mind too, if you're trying out time, restricted eating and things like that say you are at 14 hours, 14 and a half hours, and you , you feel like you really need to eat. You can go ahead and eat and that's okay.

You don't have to hold fast to just this strict, strict, strict schedule. It's a very fluid situation and listening to your body is key amongst all else . Yeah, totally. And it's not a matter of success or failure. Like if, if you've been eating or if your typical day is a fast of 10 hours and you've made it 14 and a half, that's fantastic. I mean, you've, you've definitely pushed through a barrier and you're kind of heading, heading in the right direction.

So the reason someone may be doing that , um, is some of the benefits we talked about. Another one is , um , there's this idea of longterm benefit from caloric restriction. Um, and that's something that has, has been researched for decades really. And we do know that in , in many animal models, if you drastically reduce the amount of calories, someone eats their longevity, how long they live is typically Raider , but then that doesn't work real well for humans.

So , uh , sometimes just saying, well, rather than , uh , you know, have days where I'm just eating 500 calories every day, we can space that out. And then you come to a different type of fasting where maybe you'll have three days normal and then either a day facet or even a day of time restrictive eating. Um, so again, it all, it all kind of depends on what you're trying to gain from it, I guess. Excellent.

So say we, we, we kind of have a strategic goal with this, and we're an athlete predominantly, maybe an endurance sport, and we've, we've seen a lot about, you know , using fat as fuel and things like that and how to use fasting to kind of tweak with that system. Where would this kind of come into play for someone who's out there trying to kind of maximize their aerobic training system and really work on improving their fat burning?

Yeah, I mean, I think that's just, it, that's probably the only place that this type of dietary strategy may play a role. Um , in general, fasting, decrease , decreasing fuel availability is not going to be beneficial for performance. Um , the one exception is this, where if you're trying to really work on encouraging a aerobic utilization of fat fat for fuel, like you said , um, then it may be worthwhile to do a workout at the end of a long fasting window.

So I'm not saying three days into a fast, that's going to be difficult and probably pretty catabolic, not beneficial longterm , but if you've got a, an 18 hour fast and you started off at dinner the night before, and we talked about this a little bit previously, but if , if that dinner is a fairly low Cairo carbohydrate dinner, and then you spent 18 hours fasted, you know , water intake, staying hydrated, whatever, but fasting no calories.

And then at the end of that, you do a low intensity, longer duration. I mean, not three or four hours, but you know , not 20 minutes , um, then that workout may have the , uh , ability to help you kind of dig into fat stores better. It's increased fat oxidation has been shown in numerous studies that that is the outcome of that type of strategy, but there's been some that , that question that, so it's not a slam dunk and you'll hear people argue both sides of it.

Um, I think that there's good reason to think that it does encourage that increased fat oxidation. Um, there's also performance benefits of just learning how to perform in a low fuel environment, even psychologically , uh, with, with the mind and the brain being a major limiter of our performance at the high end.

Um, and that's just my opinion, but I think, I think putting yourself in stressful situations and pushing through it from an athletic standpoint , uh, there's, there's kind of an unquantifiable benefit there as well. Absolutely. I mean, you're , you're always looking for different ways to stress the body. So your activity is , is a stress in some ways to doing that in a slightly fueled state, it seems to would make sense. Now it's definitely kind of, the more is not always better.

So trying to push to that two day fast and then doing your exercise, that's not necessarily going to be a bigger benefit. And then also doing this every single day is not going to be what you're looking for either, because I think the , uh , the fat is fuel hypothesis got a lot of hate from some of the endurance world because people were doing that almost for all of their workouts.

And the idea of thinking that you can develop a fuel or a , uh , uh , a full ability for performance without developing your aerobic, anaerobic, all the different energy systems with the different fuel sources is just kind of out there. Yeah. I mean, ultimately it's about balance.

So you can't, unless you're say a , uh, uh, an extreme ultra athlete, who's going to go for hours and hours and hours well below their threshold and can fuel that entirely with fat, for fuel, very aerobic , um, you know , unless you're fit into that category, it persistent fasted state workout, you know, day in and day out is going to be detrimental to performance.

Ideally, what you want to have is be able to train that system of using fat for fuel, but also train a glycolytic system to be able to use carbohydrate for fuel and have that high end and kind of balance out the two based on your, on your goals. So when we talk about goals, there's the athletic performance, which is that we just talked about.

Um, but if your goal is improved body composition, which we can get into, if your , a goal is just weight loss, if your goal is cognitive performance, then the prescription of that fast in terms of whether it's every day, every other day, how long it lasts , um , it's going to look different in each scenario. Certainly. So let's take a look at some of those other scenarios. We've certainly with the time restricted eating and intermittent fasting and things like that.

You've seen a lot of people talk about using that for a weight loss. Um, so do you think that comes directly from the idea of , of using fasting or is this really a , a different way to kind of help create a global caloric deficit? Yeah, I think the latter and studies seem to show that that , um, for the most part, when, when they dig in the weight loss that's seen during a time restricted feeding set up , uh, can really be contributed to, or explained by caloric deficit.

Um, there's some caveats to that, but, but in general, what we'd see is that someone who limits their eating to maybe eight hours will just by default end up eating a little bit less. In fact, I think I'd have to go back and look at the studies, but I think that typically it's around 400 calories per day, less when that's done on average, when, again, looking at non-athletes just general population using this for weight loss.

Um, so it can be an effective strategy, but not necessarily specifically due to the fact that it's, you know, intermittent fasting or time restricted eating , um, in an athletic population, there may be some benefits to body composition, but it's again, probably secondary to the fact that in that type of setup, people are going to be doing facet workouts.

And there's studies that show that when someone does a morning fasted workout, it actually , um , increases satiety throughout the rest of the day. So you're not as hungry. And so again, they end up eating fewer calories for the rest of the day for having done a longer fasting period and a workout prior to starting eating so beneficial, but not because it's like the Holy grail or anything. It just has a bit of a secondary effect in a good strategy for accomplishing those things.

Yeah. I think sometimes people will see the idea of, Oh , I've, I've done my time restricted eating it's , it's 12 o'clock. I can start eating. And then they'll, they'll, they'll overeat in that eight hour window when they think that it's kind of their , their free range. And they're like, Oh, I'm trying to lose some weight.

So I'm doing this intermittent fasting thing and exactly they go out there and they think that you can eat whatever that you want when really balanced nutrition and maintaining a caloric deficit is still, what's going to kind of result in your weight loss. The time restricted eating is just one strategy, especially for people who struggle throughout the day to kind of help maintain that.

Now, one thing that I always personally for myself, when I avoid breakfast and especially, or a very carbohydrate Laden breakfast and things like that, I find that I'm not quite as hungry. It seems throughout the day. So kinda give me some insight into what's going on when I take in that, what you used to see is this part of a balanced breakfast. I always laugh when I think of that picture of a glass of orange juice, a bowl of Cheerios, a pop tart, a thing of oranges.

I mean, it's all carbohydrates as a kid that I was raised to think that I needed before I went to school. And the two o'clock I was zonked out. So w what's kind of the idea behind that.

Yeah. So what tends to happen is if , uh, if you eat a breakfast, whether it's high carbohydrate, high glycemic index, or even kind of moderate glycaemic index , uh, you know, bull oatmeal , something, you will have a rise in blood sugar to which your body responds by secreting insulin, which causes that blood sugar to come down by forcing it into cells all totally appropriate. But then there can be an overshoot where blood sugar then drops continues to drop.

Um, and with that, you get hunger for one , uh, you may get kind of this , uh , tired feeling that like you alluded to kind of a two or 3:00 PM , uh , fog, or just kind of feeling like you need a nap. Um, and what skipping breakfast can do is make it so that you'd never get that spike to begin with. And you have a little bit more of a flat glucose curve throughout the day.

Now you'll still eat lunch and you start eating the rest of the day, but there's some evidence that you are more , uh , or less sensitive to glucose intake after a fast , um, in other words, it won't shoot your blood sugar up quite as high, and you won't require as much insulin to manage that. And so you get kind of a more , uh, a flatter curve, so to speak through the day. Uh , that's not to say that breakfast is bad far from it .

We're talking very situationally, but if you're going to go to work or school and sit there in a very sedentary environment , um, you know, maybe listening to a lecture or something like that, then having that well-rounded American breakfast of cereal, pop tarts , and orange juice is probably going to be counterproductive for those reasons.

So it seems like for the , uh, th the various people that might try, like a time restricted eating strategy, that someone who works at a sedentary desk job, isn't able to do activity in the morning and things like that, it might be a really good strategy for them. Yeah, I think so. And even, I mean, every day in our life looks different. You know, there are days where I may get out for two workouts and there may be two days where I don't work out. Right. And so you can change it.

You can change your daily diet based on what you're looking at for the day. So if I'm going to be sitting at my desk all day, maybe at a conference or traveling on a plane, then that's a great time to extend that fast window and get the benefits of that. Whether that's a little bit of caloric deficit of flattered glucose curve, some mental clarity, or not quite the , the mid-afternoon drop , uh, those are great days to take advantage of it.

But I wouldn't do that on a day where I've got maybe two workouts planned, where I'm going to do a easy run in the morning and then go to the gym in the afternoon. Uh, that's going to be a harder, harder dietary regimen , uh, to , to kind of stick to if I'm trying to support those activities. I think that's a great point that this is, this is a great tool that you can utilize, and it's not something that has to be all or none .

You don't have to every single day, not eat breakfast and do your 16 hour fast and wait until , you know, wait until lunch to have your food. Like, it's one tool that you can add to your, your toolbox to kind of take advantage of those days when you're going to either be sedentary, you have a, an easier workout and things like that. So kind of fitting it to that day that we've talked about with kind of , you know , matching your, your, your fueling to that day's activities.

But also understanding that just because you're saying, Oh, I'm doing time restricted . That doesn't mean you're doing it every single day, right. It doesn't have to be breakfast every day either . I mean, really the studies that are out there support the fact that it's probably more metabolically beneficial to skip dinner. Um, and that has to do with circadian rhythms and, and resultant hormonal responses to that.

Um, but you know, the reason that most people end up doing breakfast is it's a little bit, it's easier socially skip breakfast because dinner oftentimes is a family event, a social event. Um, and I'm all for that. I mean, that, that if it fits socially better, don't, don't sacrifice the social benefits of a good dinner for sticking to a , uh, some dietary dogma. Right.

Um, but if you've got the option to, you know , have a big breakfast lunch, skip dinner, then there's probably reason to do that. You know, if , if family's out of town, wherever you're at home by yourself for dinner , um, that's a great one to skip. Uh , by the same token, we talked about travel. If you're going to be traveling, say to Europe on an overnight flight , uh, there are circadian signals that come from eating.

You know, when, when you eat your body kind of thinks it's daytime because that's when you eat. Um, and some of the hormonal releases that, that manage food intake and digestion and all those things, they, they signal your body that it's daytime. And so if you get on a plane at say, six o'clock in Atlanta, and you're going to fly to Paris and then on to Barcelona, then there's a very good rationale for maybe having an early dinner in Atlanta , um, happened on that plane.

Don't need it on the plane. Don't eat in Paris, fly to Barcelona, and then start eating on a regular schedule for your destination when you get to Barcelona or wherever you're going. But the point is you manage some of those circadian signals so that your body's not so confused when you get there. And I mean, I can tell you firsthand that it's a fantastic way to manage jet lag. It won't get rid of it totally. But it will make huge dents and the jet like that you feel from travel like that.

Yeah. So moral of the story is don't fly with Kevin, but you can't eat on the plane. That's right. Well, within, within the U S actually , I mean, there's nothing worth eating on a plane. Anyway, the physicality cookies are just so delicious though. So, I mean, we have to be fair. We have taken flights to Europe with the kids and the flight attendants get visibly, like worried about our children who continuously say, no, thank you.

No, thank you as the food comes by, but they just turn their nose up at like, like unwrap that and eat it. You're gonna pull the cellophane off. So that's probably going to be a little bit too far to , I totally admit , um, but bring your own food. Don't need to eat it. Transatlantically maybe, but flying to California, your across a few times zones, I think that the impact is minimal. And if you've got good stuff to eat, go ahead and eat it.

I mean, I think this is a really interesting topic that there's, there's a growing body of evidence to support. Um, we've known about kind of extreme caloric restriction leading to increase lifespans and, you know , multiple species we've known about that for years, but it's not, it's not realistic to tell people, okay , just eat 700 calories a day.

And quite honestly is probably detrimental to anybody who's active and, you know, not being kept in a cage to be studied the way these animals are or in a zoo, or like, you know, it's , it's a , it's an unnatural construct where these, these studies happen. Um, and we can't necessarily just apply that to active human beings or active other animals. However, it's an interesting way to look into what's going on physiologically. And it looks like there's numerous things at play.

One is probably better glucose control , um, and just kind of general metabolic function from that standpoint. And that you're not getting either overfed or spikes and troughs in your glucose levels, insulin levels and , and all the resultant ills that come with that , uh, you know , vascular problems , uh, cognitive problems, all sorts of stuff. Um, so decreased caloric intake probably keeps that metabolism a bit more, a bit more neutral as opposed to just being up and down, up and down.

And there's likely benefit there. Um, if you , uh , if you look at , uh , cancer pathophysiology, so , um, the body and the immune system will typically clean up cancer cells in the body as they, as they arise. And they do all the time, like there's cells and DNA just kind of go awry and the body takes care of it typically it's , uh , there's by numerous processes, this happens, but one of them is apoptosis, which is what we know is programmed cell death.

Like something gets , uh, kind of outstrips its utility or ages beyond where it's able to do its job. And it has a program death that those nutrients are absorbed and kind of reused in the body. That process doesn't happen effectively if you're constantly in a fed state. And so these periods of hypo caloric or , or lower calorie intake, or even fasting , uh , actually kind of encourages that process, almost like a cleanup, a cellular cleanup. Um, and so that can have benefits longterm as well.

So you've got metabolic health, you've got kind of a cleanup of debris and, and cells that are hanging around and may become cancerous. And given that metabolic diseases are one of the primary killers in our society and cancer is another one. Um, there's reason to think that anything that positively impacts those two things could lead to longer life span , all of the things being equal. Uh, so for that, I think there's been a lot of, a lot of interest in this topic.

And it's, like I said, it's , it's, it's very interesting to me. It's, I think there's a lot there, a lot to be researched. Um, but there's also rationale, like we talked about before on a day to day basis, just with how you feel, how you perform , uh, you know, more, more immediate gratification, I guess. Yeah. I know.

I , um , I've had a hard time kind of delving into more time restricted, longer fasts and things like that, because there's always been this common conception of needing to be fueled. You're going to lose muscle. There's going to be catabolism and things like that. So as far as the idea of losing muscle, or even using fast to kind of get rid of cells that we need to get rid of, how do you think the , uh , connection is there?

Like how long until we kind of run into an issue of like, okay, this is going to start to be negative, and this is not the way that I want to do it, or what are some ways that we could really mess ourselves up trying to use this tool. It can be really powerful. Yeah. Keep, when does it come counterproductive?

Yes. Um, I think that varies , uh, depending on what your goals are, but there is evidence that if you say, if you gage engage in heavy lifting while you're fasted, then it triggers a certain, certain signaling within muscle cells that, you know, you can kind of think of it as telling the muscle, Hey, this, this muscle tissue is needed. Don't, don't get rid of it. Don't use it for fuel for the rest of the body . Like we need it.

So that can be , uh , you know , not a very intense and not a long workout, but maybe a couple of heavy deadlifts , a couple of heavy bench presses and done like five minute workout in the middle of your, of a, of an extended fast, just to remind your body that that tissue is needed. This conceptually, that's a good way to think about it.

Um, with regard to athletic performance, you, I think it's really important, not so much to worry about the timing of the fast, but what you're doing around it. So if your training plan is, is very, glycolytic very high intensity , um, then you've got, you can still do that during a fasted state or, or in the midst of multiple days of time, restricted eating.

Um, but with each day that passes, you run a greater risk of going too low on those glycogen stores and really starting to break down rather than build up. So I think it's more a matter of looking at your, your overall day, your plan and your goals, and making sure that you're not overshooting one way or the other , um, and an important thing there too is you can probably extend how long you carry on a time restricted eating schedule with in the face of more intense workouts.

If you make sure that during the time that you eat, you're getting in all those calories that you need. So if you need 3,200 calories a day to support your training and your daily life, then it's , it's okay . If you're getting those in during eight hours or six hours of eating, you'll probably be just fine. But like we mentioned earlier, the tendency during a time restricted eating period is to almost inadvertently be hypo caloric and not get in the full 3,200.

That's just a number, but if that's what you needed, you know, maybe you're getting 2,800 for a day or two, that's fine, a few days a week, two into it. You're starting to accumulate some big debts and those are gonna have to be paid eventually. That is not a pretty thing when that happens. So it's, it's really about understanding the bigger picture around what you're doing, how you're eating and making sure that you support your goals for that, for that day in that period.

That's a, it seems like it's a great tool that we can use. And it's commonly misused. I know in the world of , uh , we're like strength, athletes, bodybuilding, physique, and things like that. You see this idea of fast and cardio, which is the exact same concept of what we're kind of talking about here. But a lot of times the intensity factors is way, way high. When we're talking about these fasted or hyper-local like where you're under fueled workouts, it's a very, very easy effort.

And a lot of times you see fasted cardio, Oh , it pops up on whatever bodybuilding.com and things like that. And people go out and they get on the treadmill and they're , they're not running a lot anyway. And they run pretty hard and they're their heart rates well above there , above that lactate threshold. And you're really not going to see the benefits as you were talking about when you're doing an anaerobic workout in this under fueled state.

So it comes back to the idea of knowing what your goal is with using that tool in order to use it properly and kind of maximize your benefits from it. Yeah. And knowing your training zones, because what, what is anaerobic for me? And you may vary widely. And so , so one of the ways that we look at this with our patients is we do lactate testing. And that gives us an idea of where some, what metabolic systems someone is using to , to, to support a given effort.

So if we talk about a treadmill , um, you know, at a, at a, you know , two , what am I going to say, two miles per hour walk like a really slow walk, right? Um, somebody should have a very low lactate 0.7, just very low. Um, but that's not always the case. Somebody who's not used to doing that may have a higher lactate , uh, for the purposes of maintaining a, primarily a aerobic contribution. So like a facet cardio type thing.

You want to have a lactate generally under two , that's kind of accepted. We , we actually shoot for kind of 1.8. We work with patients. We look at, you know, their lactate curve. And if we're giving them advice on where to do , uh , a facet, fasted , cardio type session, we'll look at what effort generates about 1.8 millimoles of lactate.

Um, that's going to look different though, if , if I've never been a runner that may be a brisk walk and that's it, if I'm a very , uh, accomplished and efficient runner, that may be a seven and a half, eight minute mile. So it's , it's going to vary widely. And like you said, to go out and overdo it when you're trying to do a faster , cardio is probably counterproductive.

And within this whole idea of time restricted eating, gaining the benefits of a fast , uh, it really also becomes counterproductive in that you become catabolic very quickly and rather than being health promoting , uh , it, it becomes quite a detriment pretty quickly. Absolutely. So knowing, knowing your zones and keeping that intensity proper is , is definitely one way to maximize the benefits of this.

So what are some other kind of key rules that you would give us as far as using any sort of faster time restricted eating? I think don't be too , uh, too strict about it. I mean, you can, you can go out and set a goal that you're going to do 16 and eight or 18 and six. Um, but like you said earlier, if, if the day dictates that you start eating after 15 hours of fasting, no problem, right. Go for it.

And you still, you still gained a lot of the benefit from that day , um, be cognizant of your caloric expenditure, because if you're playing with these things, then you want to know what your goal is and , and how to get there. That doesn't mean you have to log every workout log.

Every bite that you eat is probably helpful to do that for a little while and at least get an idea of what 2000 calories looks like, what 2,500, 3000 , um, and, and have an idea of, okay , an hour on the bike usually costs me roughly this many calories, you know, 30 minutes on the treadmill is this.

And then when you start to put together this whole protocol for yourself of say, you know, 18 hours, fast, six hours eating, you know that during six hours, you need your basal metabolic rate, which you can have measured , uh , let's say, 2200 calories. And then you were, you did half an hour on the treadmill. And you know, that that usually costs you 350 calories. You can start to add it up and make sure that during that window you're getting exactly what you need to support.

Um , otherwise it's a bit of a shot in the dark and the study show us, you'll probably come in under fueled, which if you're looking to lose weight, maybe a good strategy in the short term, but for performance is probably not the best way to go about it. Excellent. So making sure that we have an idea of how we're coming into that out, say we're on our fast, and we're not going to go do a workout or just wake , waking up and go into the office.

Can I still drink my coffee or have some water to you ? Like, what's that kind of look like, yeah, I think this goes toward that very binary mentality of , uh , you know , it's either all on or all off. Um, the true answer would be, you know, if you're truly going to call it a fast, it's probably water and nothing else. Right? Some people like to throw electrolytes in the mix. Um, some people black coffee will work for others, you know, maybe a little cream, cause there's no carbohydrate in it.

Again, that goes a little bit toward goals. But also, I don't think, you know, if your coffee, isn't a sugar bomb of like basically melted coffee, ice cream, then you're probably fine to , to throw that in there. If you are in dire physical straights and a metabolic disaster, then you're going to reap more benefits by taking out all caloric intake and getting rid of all those hormonal signals that I kind of have gotten you to where you are, like you try and reset things.

And that in that setting, so being more strict is probably worthwhile. But if you're just trying to try out time restricted eating or a more extended fast , um , and you want to see how it works for your performance and your athletic performance, mental performance just throughout the day, maybe a little bit of weight loss, then I don't really have a problem with you having tea, coffee with a little cream.

I think there's probably a rationale to leave the sugar out just because of the , the insulin and result in hormonal responses. But end of the day, don't overthink it. I mean, there's even, there's a whole school of thought , uh, around this , uh , fasting, mimicking diet or a basically very low chloric intake for the day.

Uh, so keeping it, depending on how you define it under 700 calories a day under 500 , um, and this has been shown that there's benefit there and it may get you the vast majority of the benefits come from a full fast. So with that in mind, whether you put, you know, a couple of teaspoons of cream in your coffee and maybe a little bit of sweetener, probably a material.

So what if I am trying to be really strict and I've started off with my coffee and I know some people try to work around it with say an artificial sweetener, but there's still some response that your body's going to get. So how's that going to look as far as breaking the fast, if I'm still going coffee with like a Splenda or Stevia or something like that, as opposed to a sugar, I am, I really shooting myself in the foot if I'm trying to be really strict. Um, that's a good question.

I don't think that we know the answer, honestly. However , um, there are , uh , research studies that have shown that even non caloric sweeteners lead to certain hormonal responses that mimic having taken in sugar. So you may not get the glucose bump, but you may get an insulin bump because your body thinks you took, took in shooter , uh, just from various sensors in the mouth and whatnot. Um, is that terrible? Probably not on a one off, but if you're trying to be super strict, I'd say skip it.

Um , but even more importantly, stepping back and taking a bigger picture, I'm not a fan of artificial, anything personally, like if you're going to sweeten something kind of like sugar , um, you know, in moderation use a little bit , uh, and , and go for the , the real thing is as nature made it , um, there are some interesting sweeteners out there.

There are some that are notably quite bad for you that some probably aren't , uh, and then you can get into things like a Gavi and different forms of sweetener. I would just say, go for something that's as natural as possible if you're going to use it. And if you're trying to be super strict, just skip it, your body knows what sugar is and I know what sugar is and it's delicious. Exactly.

So all at all , um , what are some like main takeaways you would give us if we were to come to you and say, Hey, thinking about doing a fast how's that going to look? Yeah. I think looking at where you're starting is key. So how, how metabolically healthy is your body and what are you trying to accomplish? Because if you come to me and say, Hey, I mean, if you did come to me and say, Hey, I'm thinking about doing a fast, what do you think my first question be ? Why not?

As in, like, why would you do that? But why are you doing this? What , what is the purpose? Because that's going to really dictate everything from that point on , um, from that we can determine, is this going to be a daily strategy for a few weeks? Is this going to be twice a week for a while?

And we're going to work it in around certain workouts and activities , um, you know, are you tight to like early or pre-diabetic or early type two diabetic, we want to reverse that that's going to look a lot different too . Um, so it really depends on the why from that we can develop a program that's going to be as beneficial as possible for you, but that's going to look very different for everyone.

Um, for athletes in particular, I would say that the big thing to remember is unless your goal is weight loss, which again, this may or may not be a good strategy for weight loss. But if your goal is separate from weight loss, it's more of a performance when , whether that's mental , uh, aerobic performance, whatever it's remember that caloric neutrality, don't put yourself in a hole. If that's not where you want to be. Um, and for a lot of athletes, that's not where they want to be.

They want to fuel, it don't want to have a catabolic outcome. They don't break down day after day. Um, they want to fuel their workouts, but still enjoy the benefits of a fast. And for that, it's really important that during that time that you're eating you eat enough. Um, I think those to me are the main takeaways. And then don't be too strict.

I mean, depending again, like if you're, if you are looking at a diagnosis of type two diabetes and you're doing everything you can to reverse it, be strict, like stick to it. Um, but if that's not the case, then don't fret over whether it's 14 hours, 16 hours, if you plan to go 18, but you only made it 15, you know , do you put a little cream in your coffee that that's not the stuff to get hung up on? Um, cause that's the easiest way to kind of discourage yourself from doing it at all.

I think keeping, keeping everything nice and fluid, understanding that it's a tool, you can use it in different ways and really taking advantage of that because at the end of the day, like we know that there's a lot of benefit to it, but we don't exactly know how to dose it or really how to maximize everything. So trying different ways of doing it, trying before they fast .

I know that's something I've personally never done, but I've always wanted to try to like, just see, all right , how do I feel after 24 hours? Or you should do it and you can report back to us here. I'll I'll tune in next week. See how I do if I make it through.

Um , well, and this is something that even in , you know, as starting to come about as being a focus of , uh, even the more mainstream medical literature, I mean the new England journal of medicine did a, a review article on like all the forms of fasting and all the potential benefits. Uh, I think there was , it's been published within the last six months to a year. Um, and so it's, it's something that I think is gaining steam.

And like you said, we recognize that there's a benefit , um, in lots of situations. And now we're really in a position where we're trying to figure out how best to utilize it in different situations and circumstances. I don't think they'll ever be a right answer, so to speak, but it's a tool that we can use going forward for lots of reasons. I'm excited to dig more into it. Personally. I've tried different strategies as far as your time, restricted eating and things like that.

And it's , it's really interesting to see kind of what your body can do when you have the misconception of, Oh, I need to be in a fueled state all the time, especially as it relates to cardio and things like that, like getting up and running, you know , for the longest time I felt like I had to eat before I would go out and run how to eat before I would go out and bike. And it's amazing. And you're like, you know what? I felt I felt fine.

Or sometimes even felt a lot better on a lot of those easy rides. Cause there's no GI distress or anything like that from thinking, Oh, I need to hit this hammer gel 15 minutes before my activity. Yeah. Excellent. Now I totally agree. I've gotten hungry too. Yeah. So I guess with that, do you have anything else to add? No, I'm going to go get a snack. Excellent set . All right. Well that break my fast. If I go, if I go eat a peanut butter bar, will that break my fast?

My fast has been broken long ago.

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