Why Muscle Matters & How to Build It

The science and practice of enhancing human performance for sport, play and life. Welcome to Perform. I'm Dr. Andy Galpin, a professor of kinesiology in the Center for Sport Performance at Cal State Fullerton. In the center, our mission is to conduct and disseminate research that enhances human performance. In addition to my roles as a scientist, I also work directly with high performing athletes.

This could include Olympic gold medalists, world champions, MVP's, Saiyong winners, all stars, across multiple sports, the NHL, NBA, the NFL PGA tour, boxing, the UFC, and many more. So while I focus most of my career on sport and athletes specifically, my real passion is the physiology behind that. And so what I hope to share with you over this podcast is a deep dive into the physiology of human performance.

Now that doesn't necessarily mean sports per se. This is really human performance at its finest, most broadest definition. This could be athletes, musicians, leaders, scientists, educators, or anything else in between. Human performance really is what you want your body to be capable of. So in order to accomplish that, I'm extremely excited to share with you the physiology behind human performance in a way that is engaging, applicable, and most importantly, useful.

Today we're going to be talking about muscle, more specifically, skeletal muscle, my favorite. Now, I know when you first hear that, your mind may jump to things like sport performance and big, giant muscles and bodybuilding and aesthetics. And while that may or may not be of interest to you, I will tell you, can't really, it's a large interest of mine. You may be surprised to learn that muscle quality and quantity are incredibly important for your overall health and well-being.

Yeah, you heard that right. Quality muscle is essential for the vitality of nearly every cell, organ, or organ system in your entire body. Let me give you two specific examples of what I'm talking about. First is the connection between muscle and the brain. Now, there are many lines of evidence we could utilize here. But one that I think highlights the point beautifully is a recent study on about a half a million participants, mostly middle-aged men or women.

And in that, they found that about 30% of dementia cases were directly attributable to low grip strength. Now, that may sound alarming and or interesting to you and I promise we'll get into these those of that study and many others later in the show. Now, that was an example of muscle quality or functionality. Let me give you another one regarding muscle quantity or size and how that will directly relate to longevity or lifespan.

Once again, there's lots of research to pull from and we'll get into this later in the show. But it's very clear that being under-muscled is a significant problem. In fact, we know this is such a big problem. The National Institute of Health has an entire wing dedicated specifically to sarcopenia, which is the advanced loss of muscle with age. If you'd like some hard numbers to wrap your head around a little bit here, consider this.

Those in the bottom 20th percentile versus the top 20th percentile in terms of how much muscle mass you have on your entire body. Well, those in the bottom portion have about two times the risk of all cars mortality as those in the top. And so while we certainly are going to consider functionality or quality, most important quantity matters a lot as well.

So based upon what I've just shared and more that we'll get into later in the show, to me, skeleton muscle is by far the most important organ in your entire body. Now, in order to convince you of that, I'm going to start by telling you how it actually regulates performance across the entire system.

This includes everything from its relationship to how long and how well you're going to live, to how it regulates your blood glucose, metabolism, and overall energy production, to other factors that you may or may not also be aware of. After that, we'll get into what muscle actually is, how is the structure and the function of it determining how you move throughout the world. And then finally, we'll get into the assessment piece. How do you identify whether or not you have enough muscle?

And if you don't, how do you go about improving that? Now, before we go too much further, I'd like to take a quick break and thank our sponsors because they make this show possible. Not only are they on this list because they offer great products and services, but because I actually personally love them and use them myself. Today's episode is brought to you by Absolute Rest. Sleep is the bedrock of human performance, which is why I always focus on it with my elite athletes.

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The first is the quantity of muscle you have in the second is quality. Now, the quantity of muscle compared to other organ systems, say your immune system, your brain, central nervous system, or even like your bones, skeletal muscle is the one you have the most control over with lifestyle factors. So what I mean by that is it is the one you can manipulate the most to alter your physical appearance. Now, you may want to look a certain way or not another way that's entirely up to you.

But skeletal muscle is the place you will go to determine that. Of course, you can reduce the amount of body fat you have overall with lifestyle, but it's hard to really pick that from a certain space or place on your body. For example, if you wanted to lose fat on your triceps or the back of your arm or on your legs or so, it's really difficult to target the fat loss in that area. It tends to come globally a little bit from everywhere in your body. But skeletal muscle is different.

You can absolutely focus entirely on growing your calves or on one arm, relative to the other, or anything else you want to do. So again, of all of the different organ systems and structures on your body, it is the one you have the most control over to determine how you look. That said, I want to focus more on the second part of our discussion here, which is the quality of the muscle. So the functionality, what it's providing to your body, and how it's helping you navigate to the world.

So remember, skeletal muscle is the direct interface with the world. I know folks that are in the neuroscience department, people like Andrew love to give all the credit to the nervous system and the brain, and that's fine. Obviously, that's what's making the decisions. But skeletal muscle is the workhorse. So nothing will actually get accomplished without the skeletal muscle. It's a little bit of chicken and egg here. I get that.

But in my opinion, nothing is going to happen in your body, health-wise or actual, again, interfacing with the world without skeletal muscle. This is the workhorse of your life. Now, before we go too much further, I want to back up just a touch. I realize I've described skeletal muscle as an organ system several times now, and many of you may not know what that means or why it matters.

You see, if you would have gone on something like Jeopardy in 1990, and they asked a question of what's the biggest organ in your body, you would have probably said the skin, and that would have been correct at the time. However, hopefully, jeopardy's made a change. We realized that's not the correct answer. It is skeletal muscle by a landslide. So what it means to be an organ is that it's to create something and communicate to other parts of your body.

And it wasn't really until the last 20 years where scientists have identified and realized that skeletal muscle is what we'd say not stupid. In other words, we used to, again, neuroscientist, think that skeletal muscle just is a one-way street. Information comes in from the nervous system, tells muscle what to do, and then it executes. What we now realize skeletal muscle is far smarter than that.

It is known only accepting information from the nervous system, also from the hormones and the consistent things that are in your blood and everywhere else. It's also sending signals back out. This includes things that are now called extra kinds. So these recital kinds are, again, other information molecules excreted from muscle, in this case, in response specifically to exercise. And their direct target is other organ systems in the body.

This would include the kidneys, liver, lungs, brain, and every other part of your system. There are also other molecules that we'll discuss later, such as non-coding mRNAs that are critical to your body understanding its overall status. You see, really, the way that I think about it is skeletal muscle, given the fact that it occupies far more space in your body than anything else, is the primary key to physiology communication.

It is the biggest factor that is both receiving and extending information out to the rest of your body. So when you don't have enough of it or it is compromised, you're going to see problems in every other area of your life.

To double down on that statement, if you were to look across the literature on both skeletal muscle mass, as well as muscle quality, so think in this case, muscle power, muscle strength, or something like that, you will see connections to basically every aspect of overall human health and performance. And this is why if you were to look into the scientific literature on everything from sport performance to all-cause mortality, you'll see a strong tie to skeletal muscle quantity and quality.

So for example, skeletal muscle has been implicated in the regulation of numerous systems, which include, but are not limited to, all-cause morbidity and mortality, cardiovascular health, cognitive health, brain health, mood, inflammation, immunity, fertility, metabolic health, hormone health, bone health, and much more. Another important thing to realize is that most of your

metabolism in your body is actually occurring in your skeletal muscle. In fact, because of this, around 85% or so of the heat you generate in your body is coming from skeletal muscle. It's also the primary place in which you dispose of and regulate blood glucose, which is important for both short-term performance as well as long-term health. In fact, recent research has shown that athletes are up to 25% more effective at disposing glucose

into their muscle than non-athletes. So regardless of how you're defining human performance, whether that be hit a golf ball, 300 yards, fix your low back pain, have more focus at work, or alter how you physically appear, skeletal muscle is going to be at the center of that conversation. So how much can it really change? Let's talk about the adaptability or what we call plasticity of skeletal muscle. In my opinion, I judge the overall quality of skeletal muscle in

three main areas. Effectively, you can think of these three as look good, feel good, and play good. What that means for everyone, the first one is pretty obvious. It should look how you want it to look, and that's going to be different for everyone. People want different sizes and shapes, some folks want more size and certain muscles and muscle groups and less than others. That's entirely

up to you. The second one, feel good. This should be resilient and non-sensitive, so you should be able to engage in multiple types of metabolic processes, should be able to handle multiple types of contractions and multiple ranges of motion, etc. So again, we want resilient muscle that can do many things, basically on demand. The last one then is play good. Can we execute on the things we're asking it to do? So can I go fast when we want it to go fast? Can I go under control when we want

it to be under control? Can it be high precision? Can it be gross movement? Can it respond and recover quickly? So as we continue on this discussion, I'm going to have all three of those goals in mind that really at the end of the day, it should look a certain way. It should be resilient, be able to do many things and many areas, but then also be able to execute the exact way that you personally

want it to execute. As a quick example, when we say smooth muscle, think about the tiny muscles involved in digestion, moving food throughout your digestive tract, stuff that is really not under your voluntary control, not really going to respond and change, say growing in size, increasing in strength and response to a workout or lifestyle interventions, it's kind of the stuff that moves your life beyond your somatic or cognitive control. Now, in terms of cardiac, we're really basically

talking about one thing and that's your heart. There's a few other things that go along with that, but that's basically what we're talking about. Skeleton muscle is almost everything else. So it is your biceps muscles, your hamstring muscles, your quadriceps, the things that you have both voluntary and involuntary control over. They tend to be large muscles, but they can be the small ones

as well. Think of your inner costles, the muscles between your ribs that are contracted to expand your chest so that you can breathe and bring volume and your lungs, the small muscles in your eye that control fine motor movement and everything else like that. So to recap, smooth muscle is the stuff you have very little control over, tends to be the muscles necessary to keep you alive for digestion

breathing and things like that. Cardiac is effectively your heart and then skeletal muscle is basically everything else. It's the stuff that relegates human movement, you have both control and involuntary control of it. They can be large muscles or small muscles, but once again, it's basically everything non-smooth and non-cardiac. Now, if you've listened to any of Dr. Andrew Jimman's work, he's talked extensively about the role of neuroplasticity, which is the ability of your nervous system to

adapt or change in response to various stimuli or lack that up. Well, skeletal muscle's ability to respond like that is even greater. So it will change its nature in both the short term and now we're talking in order of seconds to minutes as well as in the long term. So it's ability to alter how you feel and perform is extensive. In order to understand that, we need to talk briefly about what muscle really is. So what exactly is skeletal muscle? Well, let's start all the way back at the

beginning. In your body, you've got somewhere between six to seven hundred different muscles. Now, we don't know the exact number. There's no scientific consensus on that. In fact, I remember fairly recently, a paper came out arguing for the identification of a fifth quadricep muscle. So the tradition is that you've got four hands quadricep muscles in your quad or your thigh there and they had argued that they had identified a fifth one. Now, I don't know the literature on that

as well anymore. But the point is you've got a large number of muscles throughout your entire body. We tend to group them into muscle groups. So continuing with the quadriceps theme, we tend to call that the quad muscles, although that is actually four individual muscles. Your biceps are actually a combination of several different biceps muscles, your triceps, etc., etc. And so we've got all the muscles in our body. We've got these subgrouping of muscle groups. And then within each

individual muscle, you have hundreds of thousands of muscle fibers. Think of this like a ponytail. So while you'd call that ponytail one thing, it's actually just comprised of thousands of different individual hairs. So when we want to talk about the individual hair, we say hair follicule,

we want to talk about the ponytail's unit, we say the ponytail. So the same thing would happen. I could talk about your hamstring muscles, but really am I talking about one muscle, say the semi-member nosis or semi-tendinosis, the hamstrings as a group, or the individual fibers within each of those

individual muscles. So drilling down on that, if you can imagine going back to the ponytail, there is a layer of connected tissue or fascia that surrounds each of these muscle fibers that holds them together, but that's what actually collectively makes them one unit and why we call that a muscle.

That muscle is then wrapped around further with more connected tissue. All that comes together to form a tendon, that tendon then connects to the bone such that when you activate or contract any of those muscle fibers, it contracts the muscle as a whole, tends to contract the entire muscle group, that entire muscle group comes together, goes into a tendon, that tendon then pulls the bone.

So the easy example against sticking with the quads is an easy theme. You contract any of the muscle fibers within, say, the vasisaladuralis, the muscle that is on the far outside of your leg, that is one of the quadricep muscles. The entire quad tends to feel like it's contracting, that then goes over through the patellite tendon, the patellite tendon inserts on the front of the lower leg bone, which causes the lower leg bone to lift up and for your lower leg to extend.

That quickly is how muscles work and how they actually cause human movement. It's through one, the activation of the muscle, two, the contraction of the muscle, and then three, the muscle pulling on connected tissue, which makes bones move. Now the amount of muscle fibers you've got in each muscle varies pretty highly, and it's somewhere in the neighborhood of one to 300,000 individual fibers. Interestingly, this number will double during the first few months of your life,

and then basically stabilize by the time you reach adulthood. Now, as I mentioned, you've got somewhere between 100 and 300,000 fibers per muscle. One example, the vasisip's breaky eye has been shown to have about 250,000 muscle fibers. And so if you ran some quick math there, that would mean most of us probably have somewhere in the neighborhood of between 125 to 250 million muscle fibers throughout our entire body. And these fibers are extraordinarily unique in

all of biology. For a couple of reasons. Number one, they are absolutely huge. They are some of the biggest cells by volume in all of biology. It is common to have a muscle fiber that is up to two to three centimeters long. And in fact, many have been shown to be up to 10 centimeters or so long. Think about the sartorius muscle. This muscle that goes from the inside of your hip bone that

front side there and goes all the inside of your knee. It is theorized, and some folks will say in physiology, Lord, that you can have a single muscle fiber that runs the entire length of that. I don't actually know whether or not that's true, but it would not be rare to see a fiber that is again four to five to up to six inches long, which is enormous. In terms of the width,

same kind of idea. You'll see these things as extremely large, right? Somewhere between four to five micrometers in terms of cross-sectional areas, my promenader squared, to give you a little bit of concept of how big that is. Number one, you can see that with a naked eye. I could pull up in my laboratory a pair of tweezers, a single muscle fiber from a human. I could hold it up right now, and on this camera, you would absolutely be able to see that. Both on camera as well as with your

naked eye, if you were within even five to ten feet of me. In terms of cross-sectional area, you're looking at something like four to five thousand micrometers squared, which a little bit of context there. One time actually, I had a long established power lifter, as well as anabolic steroid user in my lab, and we biopsy this individual. In his muscle fibers, we're closer to nine thousand. The closest equivalent we found there was actually a rhinoceros. So muscle fibers are

not only large in terms of biology, but the ability to gain size is extraordinary. As again, I said earlier, one of the things that makes skeletal muscle in humans especially unique is the ability to respond and adapt based on stimuli. In fact, it seems to be quite unending. Now, we'll come back and talk about muscle fibers, size, and how to develop it a little bit later. But getting back to this idea of fiber number. As I mentioned, it's not to be fairly fixed

once you reach adulthood. However, it is extremely clear that this number will go down with aging, unless you do something proactively to prevent that. It's actually also very clear that this number can increase with anabolic steroid use. Now, this concept of growing new muscle fibers is called hyperplasia and something that has been hotly contested in the exercise physiology world for many, many decades. Now, I will give you a little bit of a behind the scenes here. I personally

am always been a big believer in hyperplasia happening. I won't say the science is strongly in my support, but it's one of the passion projects that I'm not going to give up on. Okay. Now, what I'm really talking about here is there's no question whatsoever that new cells can grow. That's not really the debate. What is up for discussion, though, is whether or not that happens as a normal response to normal training in healthy humans. There is strong evidence that animal steroid use, especially

over a number of years, can increase that number. And again, we know it will decrease with aging. Now, when I say animal steroid use, I'm mostly talking about testosterone here. Now, please, so I can be ultra clear here, I am not encouraging anyone to utilize antibiotic steroids or testosterone. I'm not a medical doctor. If you are interested in any use of exogenous hormones, that's something you need to work out with your personal position. This is not, again, me encouraging or recommending

the use. I will not also suggest it will make your muscle healthier or any better. There are many factors to think about when considering exogenous hormones. And I am not the person to take advice from on those things. We also know that consistent strength training will prevent the loss of those muscle fibers over time. Whether or not you can, again, go above and beyond your normal set at a normal age with just basic strength training, I guess, is still up for debate. There are maybe some

things if you catch me off camera. I'm willing to share with you. But according to the current science right now, that's the best we can say. So what this means is you've got two paths to changing skeletal muscle structure and function. The first is increasing the amount of muscle fibers, as we just got done discussing. That's probably quite challenging to do in normal settings. And so when I spend more of our time talking about how do we alter the metabolic and contractile

properties. So another thing that makes skeletal muscle extremely unique is the fact that it is multi-nucleated. So now remember, the nucleus of the cell is what holds your DNA. It relegates all activities until the cell to grow, shrink, die, repair, or any other necessary function. The overwhelming majority of cells in all of biology are single nucleated. Some of them actually get very interesting when they have two or three. But skeletal muscle has thousands per cell.

This allows it to actually have such extreme size because now we have more relegation centers throughout it. I can give you an analogy here. Let's imagine you're running a business and you want to have a branch manager at every one of your offices. Well, if you only have one branch manager, it's hard to have an office in Chicago, New York, Dallas, and Seattle. Too many little things happen

in local areas. It's hard to relegate and to change things quickly. But if you could put a manager in every single location, the success of each branch, as well as the speed and turnover, goes up. That's effectively what your muscle cells are doing. They're putting a lot of nuclei in a lot of different places so that allows not only the size to expand, but where this really matters is the adaptability. Your muscle is hyper responsive to things that are happening in a short

time window across a broad domain of insoles. What I mean, this could be responsive to physical contraction, to blood flow, nutrient availability, glucose, oxygen, hormones, lifestyle factors. All of these things are being measured and monitored by skeletal muscle. Because it has the ability to adapt in multiple segments, it can do that and it can do that very quickly. Giving you some firm numbers on this nuclei, let's say that biceps breakie, I muscle, we talked about a second

ago, was 10 centimeters long. It may have something in the neighborhood of 3,000 nuclei. If you were to then count up all the muscle fibers in total, this would mean you would have in the ballpark of 750 million nuclei in the entire biceps muscle. You extend this out to all 600 plus of your muscles, and that puts you somewhere in the neighborhood of around 500 billion nuclei throughout your entire body. That's how responsive and adaptive skeletal muscle is to everything you're doing in

your life. We're going to talk a lot more about these myonuclei in future episodes, because as I mentioned, they are the primary place that are going to regulate how your muscle cells respond and change to external stressors. But what regulates the contractile and metabolic properties? That's actually something different, and it's what we call the muscle fiber type. You've probably heard of this referred to as a fast switch or slow-twich muscle fibers, but it actually extends beyond that.

Now, on the surface, that's a fine, broad explanation, but we can go a little bit past that, and I think it's helpful to do so, without being unnecessarily exhausted. Really, fibers can be classified as the following slow-twich, or another way to say that is type one, and then your fast-twich fibers are broken down into two major categories, your type 2A, as well as your 2X fibers. Many of the properties

are the same between all these fiber types. The micro anatomy, how they're designed, all the things we've talked about, how they're wrapped in connected tissue, their myonucleation status, etc., etc. The properties that are really distinct are, again, the contractile and metabolic ones. Slow-twich fibers tend to be, but are not always smaller. In fact, in endurance-trained individuals, they can often times be larger than fast-twich fibers. But their contraction is exactly that. The twitch,

or the speed of contraction, is slower. It doesn't necessarily mean the strength, or force behind the contraction is smaller or less. It's just that it contracts a little bit slower. The advantage, though, is they tend to be highly fatigue-resistant. They are better at utilizing phallus of fuel source. They have more mitochondria, and they're overall good at what we call anti-gravity

or postural. So when you think about slow-twich fibers, they tend to be the ones that are on kind of all day, keep you upright and erect, keep you moving, and keep you at a low level of contraction, but continuously. Fast-twich fibers, particularly the 2A fibers, are really the opposite. So they're going to be hedged more towards fast speed of contraction. But really, they're not particularly

effective at fatigue-resistant. They are going to prefer using things like phosphocreatine or carbohydrates as a fuel source, and are not as effective at things like fat or long-term sustained contractions. The third and final type 2X are the fastest of the bunch. While you're 2A and fast-twich fibers are somewhere in the neighborhood of 5 to 6 times more powerful than a slower type 1 fiber, a 2X fiber is in the neighborhood of 20 times more powerful.

The downside is we don't really have any good evidence of normal humans having many, if any, pure 2X fibers. Oddly enough, we see it in extreme muscle-dissue situations, things like spinal cord injury or coming back from extended space flight or situations like that. And so there's a lot of mystery still behind these 2X fibers. We can get into that again and maybe

more detail a little bit later. So on its surface, while we really have these three distinct unique fiber types, type 1, type 2A and type 2X, it is really appropriate to discuss basically the type 1 and the type 2A's from now on. Now, within any individual muscle you have on your body, the proportion of fast-twich to slow-twich, in other words, the amount of fast or slow-twich fibers in that muscle varies widely from muscle to muscle, as well as from human to human.

Now, that actually determines a lot about the function of that muscle. For example, if you take, say, the soleus muscle, which is one of the small muscles behind the back of your calf there that goes into the bottom of your heel, that is heavily based towards slow-twich muscle fibers. Depending on the person, it would be something in the neighborhood of 70% tall, we have the 90% plus percent slow-twich fibers. And that's because the primary purpose of the soleus is to keep

you standing and moving all day. It's not meant for explosive power or sprinting or jumping or anything like that. If you compare that to the other major muscle in your calf, the gastrocnemius, that's almost the exact opposite. And a lot of folks, it is 60 plus to 70 or 80% fast-twich fibers. So the gastroch is there for the exact opposite. It is there for the explosion for the jumping and sprinting and not necessarily to keep you upright all day. Now, that's not necessarily true of other

animals. In fact, this is one of the things that makes examining research in this area important to pay attention to whether you're looking at a study from a rat or a mouse, a cat, a bear, or any other animal. Is that is different? In fact, mice, the soleus is almost exclusively, if not 100% slow-twich. And other muscles like the plantarous might be the opposite, 100% fast-twich. And so why there's clearly important information we can gather there is not necessarily a direct

and equal comparator. So as I mentioned, the amount of fast-twich and slow-twich, the fiber proportions in the muscle groups varies within your own body. It also varies from person to person. So if I were to biopsy myself as I have several dozen times, I would know and see that, say in my vasocilar ralus, the muscle on the outside, which is the most common muscle to biopsy for a number of reasons. It has the least amount of nerve innovations. There's no major blood vessels flowing

through there. It's easy to access. It tends to be quite large. I don't have to go past any other muscle groups, etc., etc. So within that muscle, I have seen people in my laboratory as high as 90% plus slow-twich, as well as up to 85% fast-twich, and everywhere in between. And so the quadricep, again, the VL specifically here, is meant to really be responsive to training. And we'll talk about this more later. Other muscles like the solius, spinal erectors, other muscles saying your

fingers or eyes are not necessarily going to change as much. It would be very difficult to convert your solius into an exclusive fast-twich muscle fiber, because it's really meant to do one job. And the overall stimuli that you provide to it is fairly similar. It doesn't really matter what kind of exercise or training intervention you put, how many plyometrics or sprints you do. The vast majority of time that your solius is contracting, it's still because you're standing.

And so there's just not a lot of change that can happen there. The VL is quite different, since it is so important in all knee extension and really hip movement, it's going to be hyper-responsive to what you're asking you to do. So again, can vary heavily within your body, as well as from person to person. And we'll talk about more of this stuff later, but as you've already heard me allude to, your fiber type, again, the proportion of fast-towel

twitch is hyper-responsive to lifestyle. We know extensively for decades now that it will respond to both changes in exercise, as well as the removal of that. So some of the classic Dallas bed rest studies where they put people into bed where their head was something like six degrees below their legs. So you can imagine laying on a bed with a slight backwards tilt, so your head is a little bit below your feet a little bit above. And we've done this for up to 50 plus days.

And what we're doing there is trying to simulate both space flight. This was initially done in preparation for thinking humans were going to go to the moon or further for extended time. As well as it's actually representing nice model of aging, you can actually simulate upwards of a decade of aging in about 10 days of bed rest or so. And so we get a really good grasp of what happens when you go into disuse, similar for if you have to go into a cast,

post surgery or something like that. So we see in those models of inact forced inactivity as well as any number of exercise training studies looking simply at individuals cross-sectionally. So those that have exercised for long periods of time throughout their life compared to those who haven't. Any of these interventions you want to look at. And we see hyper-responsiveness in your fiber type profile based upon your physical activity. Other interventions that are less well

understood but are also actually quite interesting that we will discuss in depth later. Things like nutraceuticals, vitamins, minerals, vital chemicals have been shown to alter fiber type in extreme concentrations. Now whether or not small changes in your diet say how much carbohydrates or protein you're eating or any supplementation can actually reach concentrations high enough to alter fiber type is yet to be determined. I'm not really aware of any research showing that. But certainly we

have seen that in many models again where we can give them non-physiological doses. But even stuff as well as hyperbaric or extensive oxygen concentrations alterations in CO2 intake and things like that have also again mostly in animal models shown to alter fiber type. So whether or not this actually happens in a normal human circumstances is not as relevant right now. But it's just highlighting the concept of how responsive this muscle is to everything you're doing in your life.

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perform to receive 5 free travel packs plus a year supply of vitamin D3 plus K2. So in my opinion the key take home is that things like your fiber type again which regulate the contract on nature how fast and powerful your muscle fiber is contract as well as their metabolic properties how effective they are using fats and carbohydrates as a fuel source how efficient they are at bringing in nourishment and getting out waste products much of this is regulated by its fiber type

and your fiber type in general is responsive to changes in activity. Now if we would have to compare the responsiveness of the fast switch fibers to the slow-twich fibers it is very clear fast switch fibers are more reactive to things like physical activity changes whether or not you can

increase or decrease the amount of slow-twich fibers in response exercise I think that evidence is clear but it is of a much smaller magnitude than the plasticity within the fast switch fibers now why that's critical then is unless you do something about it from an exercise perspective

you're going to lose many of your fast switch fibers as you age a really nice example of this a paper published in the last few weeks looked at lifelong strength trainers now this is interesting because while we are just starting to get data on lifelong exercises almost all of that has been

in aerobic or endurance based exercises we're just starting to come on board with these lifelong strength trainers and what that paper found was that that activity to strength training basically over your entire life was able to preserve fast switch fiber concentrations however the endurance

training was not and so it was not to say the strength training is more important or better for your health at all but it is simply saying these fiber types are lost you're not able to get them back but you can preserve that or ameliorate that loss by chronic strength training now you're

going to care about these fast switch fibers for a couple of reasons while we will acknowledge that both fast and slow fibers are critically important for overall muscle health what makes fast switch fibers unique is a few things the first is that again they express the greatest capacity for force

and power production this is obviously critically important for young folks trying to enhance their club head speed on their driver when they're playing golf or individuals as they move throughout age think about scenarios in which you need to move your foot in front of you to catch

yourself from a fall you want to be explosive enough to go upstairs without a fatiguing you need to have power to lift something up overhead quickly before it collapses back down and you are any number of reasons in which you need to have strength and power as you age now the way that you

regulate force production extends beyond just what the muscle fibers themselves can do unfortunately I've got to get a little bit of credit back to the neuroscientist folks here because really this is a combination of nervous system as well as muscle fiber characteristics all of your muscle fibers

are combined into what are called motor units so the definition of a motor unit is the motor nerve as well as all the muscle fibers within that package now all those fibers within that motor unit will be of the same fiber type so fast switch or slow twitch and they're not necessarily

laying next to each other in the muscle they are spread out both superior and inferior they're deep within the muscle belly they're kind of all spread out there and this allows you to control and not have spastic movement so when you activate a motor unit not only does this contract all

of the muscle fibers in that unit it contracts them all fully that's called the all or an unprinciple and so when you flip the switch and turn on that motor unit you pass that activation threshold it activates and contracts all the muscle fibers in that unit to their fullest potential

what you can't do is turn a muscle fiber itself on at 60% or 70% or 80% so the only way you relegate force production across an entire movement is to actually turn on or off more or less motor units the example here say i would like to take my hand and reach it

up towards my eyeball and lightly touch my eye now i recognize and realize this is only going to take a small amount of force to move the weight necessary to move my hand to lightly touch my eye if i were to do that too hard i would smash my finger into my eyeball and that would hurt and

so what i do is i start with what are called low threshold motor units so these are motor units are very susceptible to firing or contracting and they activate in this case very slow and metabolically efficient muscle fibers the type one muscle fibers and so what it says is i kind of

start with the least amount possible physiology is very lazy like this and so i'll start with the least amount of force necessary and this allows me to move very slowly but with a lot of amount of control and now if i realized that actually i had a five pound weight attached to my wrist and i

had to lift my hand with more force than i thought i needed i would turn on more and more motor units and if i realized that i had that five pound weight and then i added a ten pound ball to my hand and any more and more force production i would slowly turn on more and more and more motor units as we continue up this cascade again the size principle is telling us we start with the lowest threshold smallest motor units so this is not only tends to be slow to muscle fibers but it's

also oftentimes but not always motor units that have less muscle fibers in them the amount of muscle fibers in a motor unit can vary highly several of them in your eye can be as low as a couple of dozen muscle fibers in the motor unit and those in your glutes might be several thousand muscle

fibers so even if i activated one motor unit in my eye i would get a small amount of force one motor unit in my glute might produce you know hundreds if not higher amount of force per motor unit because i have more muscle fibers in that in addition the muscle fibers might be of larger

size in the glute and smaller size in the eye because we need more motor control there and less force production something like the eye again is meant to be highly precise with its movement very low margin of error i don't need to get there particularly hard i need to get there sort of

quickly but i need to be in a control the glute in this example this is your your your butt muscle what up in any of your large butt muscles they don't necessarily need to have a lot of fine tuned precision with the movement they just need to contract with a lot of force and so the way that

these motor units is set up is in large part determinant of how they produce force and then again what the function of that muscle actually is so to go back to what we were talking about a second ago if i'm trying to produce this finger into my eyeball i need to produce more and more force

i slowly activate more motor units if i've realized the point where i need more force beyond that i will increase and start activating the higher threshold motor units that also now start to tend to be faster twitch motor units and if i need extreme amounts of force i will activate the

highest threshold which are the highest and probably where we're going to get into our type 2x fibers if we have any of them at all and so what happens if we're playing the story backwards is any movement at all in a muscle almost always includes the slow twitch motor units but only

when i start demanding high force production do i activate and engage the fast switch muscle fibers if i then go weeks months years or decades without doing anything of high force those motor units just never get activated eventually what can happen is denervation which means the nerve stops

attaching to the muscle fibers many of the muscle fibers die off we talked about that earlier right the amount of muscle fibers in the muscle reduces with aging if you don't know anything about it and then also we see changes in motor units so not only is our ability to produce force go down

but our motor control goes down because we've lost the amount of motor units going into a muscle sometimes we can see what happens called muscle fiber type grouping and so we'll see a nerve innovation that acts on that that is gone if you will the muscle fibers are still viable

and so in neighboring motor unit will actually obtain them and if they were say a fast twitch muscle fiber but now they're in a slow twitch motor unit they will convert that fiber type over to slow and so you see these big patches or groupings of slow fibers as opposed to them being spread out

throughout the muscle which reduces our motor control and smoothness of muscle contraction so we're going back to our original point here it's incredibly important that we do something to preserve our fast twitch fibers because if we don't we're going to lose them and that then becomes

extraordinarily difficult to bring them back especially once we've lost the fiber number returning muscle functions that your strength is actually very manageable through aging but increasing the amount of muscle fibers as we age it is very difficult so once we lose them they're basically gone

for life before we go any further let's quickly go back and recap what we talked about the importance of skeletal muscle extends far beyond support performance or aesthetics in fact it's important for a number of physiological factors across basically every organ system in your body we also

know that skeletal muscle is uniquely responsive to changes in the external environment it is hyper adaptable to things like changes in physical activity nutrition or various other lifestyle factors in fact what I would call the superpower of skeletal muscle is its ability to respond and adapt

both quickly as well as permanently we talked about how the muscles fibers themselves are multi nucleated which allows them that extended adaptability as well as come in various forms fast twitch and slow-church fibers the fast twitch fibers being more difficult to preserve and probably require

some sort of steady and consistent exposure to high force demands over the course of your life in order to maintain so what I like to do now is walk through the three eyes investigate interpret and intervene for both muscle quality and muscle quantity and I want to do them separately and that's

because while there is a giant overlap between the two they are independent factors let me give you an example while there is a clear relationship between muscle size and muscle strength such that generally bigger muscles are generally stronger that's not necessarily always the case we can see

number of examples here take any sport that is a weight class-based sport wrestling boxing weight lifting power lifting generally the best of the best will increase their performance in this case say strength as muscle size goes up so clearly there is a relationship between if you have more

muscle mass you potentially have the ability to create more force but that said if you walked out to the general population or even an athlete's just because you find an athlete who has more muscle that doesn't necessarily mean they're going to be stronger so again there's a clear relationship

here but it is not necessarily one to one in addition it's incredibly clear and simple to increase strength or power without necessarily changing muscle size at all these are all protocols we will go over and discuss at the end of this of our episode today but there's a relationship here

in fact I think a really nice way to highlight this even further is a recent publication of mine now this was led by a colleague of mine Tommy Wood a neuroscientist at the University of Washington and what we did is we went into the national database this is what's referred to as anhaines so this is a giant national database of kind of a study that they run every single year they collect a bunch of data from participants they put them into these big open source pools and they may do IQ

testing strength testing blood work etc etc and scientists can come in and use these for any purpose now they've been running anhaines for several decades and so you have many many many years of analysis you can go back into and poke around in well Tommy and myself and the rest of our team

did that and in our paper we found a couple of interesting things here within the population of participants that we analyze there was no relationship whatsoever between their physical strength and their muscle mass in fact there was also no relationship at all between their

amount of muscle mass they had and their physical activity background what this tells us is in this population alone they accrued their muscle mass from non-exercise pathways what we did actually find was a strong relationship between muscle strength and cognitive function but that's

something we'll talk about in a further episode so my point here is when you look at the relationship between again muscle mass and strength they can overlap they can also not we can see further evidence of this when we look at things like mitochondrial health of testosterone concentrations

range of motion a lot of these things are somewhat linked to muscle size but not necessarily in the last example think about this as if you were to take somebody who has more muscle mass that will tell you actually very little about their range of motion or flexibility

if that extends to a certain point of course excessive amounts of muscle mass may start contributing and so again there's an overlap there but there's so much distinction between them too I think it's important that we actually treat them as almost separate variables we're going to start

off with muscle quantity or muscle size the gold standard here in research would be to use something like an MRI or an ultrasound to get a high resolution cross-sectional image of an individual muscle or muscle groups think again the quadriceps hamstring muscles elbow flexors etc etc the benefit of

this of course is high fatality accuracy and precision the downside is it's really only telling you about that individual muscle or muscle group it's really only covering that portion of it so where the MRI is shot it may necessarily cover say the part of the quadriceps that's close to your hip

or close to your knee if the MRI was taken at say the midpoint of it doesn't really allow you to access or compare the right leg to the left leg unless you also image that leg and then really from this conversation the most challenging part about that is it is extremely unrealistic for

most people to do this would cost you a ton of money and be very challenging to get access to so it's not a real viable solution for most people that said new technologies are coming online there are companies like springbok which allow you to do exactly what I just talked about so this

is a full body MRI and this is quite different than using something to say scan for early cancer diagnosis or something like that this is really for the assessment of muscle quality rather and so you can go in an MRI takes about an hour or so and they will be able to capture an image each

individual muscle you have in your body and give you a visual in three dimension feedback of the muscle volume of them which again allows you to compare say all the muscles in your rotator cuff to each other compare the one on the right side to the left side front side to back side

etc etc these are available throughout at least america right now in a number of MRI facilities it is quite expensive still for the average consumer and it's not usable and available again worldwide so if you want to go after a gold standard that would probably be your best bet

if that's not available or you're more interested in something that can be used anywhere you have a couple of other options and those would be things like your app mendecular muscle mass measurement or your fat free mass now both of those metrics can be used to create what's called an index

and a second here i'm going to tell you what some of those standard numbers are and those are widely available based on your age or sex to be able to get an idea of where you should be at on those scales but quickly when i say app mendecular what i'm talking about is basically

how much muscle do you have in the appendices so your arms and legs that differs from your fat free mass index and it's important for me to point out that's not necessarily representative of your total amount of skeletal muscle that actually can be measured in other ways and would be

a separate idea so what i mean by that is when you think about your body if you want to globally say okay we're going to bucket everything into the amount of fat i have and the amount of non fat i have that's not necessarily only muscle it includes things like water muscle glycogen bone minerals

and things like that and so it's actually a pretty decent estimate of how much muscle you have but not nearly as precise and specific as again some sort of MRI imaging could give you now in order to appropriately calculate these values the best ways if you can get yourself into a dexascan

or something like that those are traditionally a hundred to two hundred dollars or so available in america and plenty of other countries worldwide so a little bit less challenging and certainly more cost-friendly than the the previous MRI stuff but not free either and so still maybe outside

of your cost range if you want to take a step below that most home scales come with the ability to use what's called BIA and so this is effectively going to tell you your body fat percentage you can use that in combination with your height and get a rough estimate of your fat free mass index

again once you go down in the scale scientific accuracy you start to lose some fidelity of measurement but for a lot of people that exchange of cost difficulty accessibility might be worth it especially if you're just looking to see if you're close if you're trying to see whether or not you broke a

world record we probably need to go a little more accurate method but for those of you that are just trying to get a basic understanding of am I significantly undermuscled am I okay where am I roughly at those are absolutely fine metrics to take and exam fat free mass index or ffm

9 is probably the most established metric to look at here so I'm going to focus mostly on that one interesting enough there is no fundamental way to calculate this there's a lot of new ones that can go into this that can alter your numbers in a decent amount of way so it's important not to

confuse you even more but I do need to add that that is not as simple maybe as one would would hope your hydration status on the day and other factors like that can alter it enough so again if you're looking for high precision maybe pay attention to that but if you're just trying to get an estimate

this is still going to give you phenomenal numbers there's also hundreds of papers published on this and so you have a great scientific background to give you that context of where you're at as an incredibly rough number when we're looking at that ffm i so that fat free mass index score for men

I generally want to see them coming in at over 20 and for women something like 16.5 again this will scale up and down based on age and you can look at a chart to see exactly where you're at I'll give you some examples here in a second but that's kind of the collective number I want to look at now to give you a little bit of context of what some of the gold standards are here of total amount of muscle mass we can have a little more fun I want to take you all the way back to 1995 there is

this classic study that came out and it basically said all right the average gym goer is something like the neighborhood of 21.5 to 22 on an ffmi score and they actually theorize at that point that the only way to get past the score of 25 was to be to use exogenous hormones and again specifically

testosterone now another reminder here I'm not encouraging or promoting the use of hormones especially outside of working directly with your doctor but this is what they're establishing what they're trying to identify is what is the genetic limitation of muscle and in other words how much muscle can

I normal human have outside of using exogenous hormones and the answer they came up with was 24.8 or was sort of roughly 25 that's been disputed since then but that gave us a ballpark and understanding so when you're looking at your scores if you realize that you're you know certainly

you know in the 2425 area this probably puts you close to what normal people are going to be outside of again exogenous hormone use but there's a lot of examples where people blow way past this of course we never necessarily know if somebody had used things like testosterone in the past but

I'm gonna make a pretty good argument for you right now that it's absolutely possible to go past that in fact if you look at someone like Arnold Schwarzenegger and his heyday kind of at his peak of performance his FFM my score was about 28 now we obviously know Arnold has his history

and past with exogenous hormone use and so that still doesn't really change the case of saying well can we get past this 25 marker naturally well let's look at some of the evidence here to give you a little bit of of scoring context here if you're at 23 and a half remember 25 is the established

limit what we think to be natural Arnold was at 28 with extensive steroid use if you're at 23 and a half for most men this is going to put you in the 99th percentile so already puts you in a phenomenal position however there are data initially the first set of studies came out in sumo wrestlers

and now these are individuals that were well over 400 pounds giving them something in the neighborhood of 268 to 270 pounds of lean body mass now again that doesn't mean muscle mass lean body mass is including bone and water and things like that but still you know 260 year so pounds of lean

body mass is a ton to move around in your system this gave them an FFM my score of about 35 now there's actually a famous case report that came out of one of the best power lifters of all time rate Williams now of course his name wasn't used in the paper but effectively

ever knows who that was and he scored a 41 on that metric which just tells you how enormous and an incredible athlete that rate is again don't know about his steroid use the vast doesn't matter what I'm trying to show you right now is just what is the human potential for total amount

of muscle mass we can put on a frame now the magical number that tends to be thrown around here in terms of amount of lean body mass what can have is somewhere in the neighborhood of 110 to 120 kilos translation 230 pounds or so something like that the example I gave you earlier of course a little

bit higher than that but that tends to be the kind of spot we can be as you start manipulating body weight hydration status what that does to muscle glycogen pulling water this is someone again this can alter this number sort of day to day so it's a little bit harder interpret but that's the kind

of number we're going to put in terms of what this this would put you in in terms of absolute muscle mass probably 60 kilos or so and the reason is maybe we'll back up one quick second lean body mass of let's just say 120 kilos it's kind of the upper limit of what we're thinking to have

well about 50 40 some between 45 to 50 percent of that will actually be skeletal muscle and so if you have 120 kilos of lean body mass and half of that is muscle this would give you the stratosphere of about 60 kilos or so of total amount of muscle mass that's about the upper

limit of what you'll ever see a human can have obviously the numbers I'm giving you here are all and men for women that number gets significantly lower but that just kind of gives you a ballpark of how much skeletal muscle one could have how much lean muscle they would have and then what

their corresponding ff and my score would be there's two other things I want to point out before we move on and the first is dealing with asymmetry now we're going to talk a lot about functional asymmetry so when when muscle is stronger than another advice for us but the actual

amount of muscle size matters as well we don't have as much concrete data on this and it also depends on your activity so for example if you are an athlete of any kind it may be who view to have some amount of asymmetry this allows you to create things like rotation and torque to be able

to throw a baseball 100 miles per hour or to hit a golf ball 400 yards or whatever the case may be but that said there's clearly a point in which asymmetry within a muscle from side to side front to back etc is detrimental functionality is different in terms of quantity right now some folks are going to say 5% others might cut that line at about 10% so if you were to get an analysis and look at say how much muscle you had from a dexascan you're able to identify maybe your right leg versus

your left leg or something like that you would want to keep an eye on about that 10% and anything more than that is probably going to be a flag that there's some sort of issue or potential issue in the future so total amount of muscle mass ff and my is a great way to go about it a symmetry pay

attention to more than about 10% and a lot and the second thing I wanted to point out here is what does it look like when I gained too much muscle and want to be clear here and I believe that we've showed that in the recent paper we published in that is excessive amounts of skeletal

mass is not detrimental in any way so there does not seem to be an upper limit where it actually starts compromising your physical health now of course if you've gained the muscle from non-exercise venues like what we saw in our enhanced database in our recent paper then that's not great so an

example here would be if you've just gained a bunch of body fat and because of that some muscle came along for the ride that would be what we consider to be muscle that I got accrued from non-exercise habits this is not going to be advantageous to your health but if it is accrued from exercise there

doesn't seem to be any evidence at all that suggests this is negative there are some papers out there that I think have made mistakes and identifying that after a certain point an increase in muscle mass is actually negative and again having analyzed some of those things myself in our recent

paper I think we found clear evidence that that is not the case there are other practical considerations if you've exercise excessively you've done it poorly or other things that have led to injury of course all those things are true what I'm trying to argue is the simple fact of having

additional muscle mass itself is not detrimental to health in any way can be associated with other things that are bad for you that lead to injury and other metabolic problems but the excessive amount of muscle mass on its surface is only going to aid in both your health and performance

we're going to make a number of these charts available to you in the show notes but again please acknowledge that they do vary a little bit from study to study so depending on which population was in a particular paper or how it was analyzed the values might be a little bit different but you're going to get you pretty close nonetheless I want to give you a couple of numbers just to get you started though now these work on percentiles what this means is when I say one percentile that

means the lowest amount of muscle mass 99 percentile is the highest obviously as we've been describing you don't want to be low in muscle whether you're an athlete or someone just interested in overall wellness and health longevity higher is better I actually personally prefer people to be

in the 95th percentile or more but I'm going to walk you through what this kind of looks like across the 25th 50th 70th and then potentially up to 95th percentile for men to be in the 25th percentile your FFMI score would be about 17.9 and women that would be 15.1 now notice how as you

go from the 25th to 50th percentile again representing right in the statistical average or right in the middle you've gone from for men 17.9 up to 19.1 or so and for women you've gone from 15.1 up to 15.9 or almost 16 and so these numbers are not going to be huge in terms of what it looks

like on paper but that does represent a large change in the total amount of muscle mass you have if you were to go from that 50th percentile to 75th you've now gone up to 20.4 for men and 16.8 for women as I said I actually prefer people to be in the 95th percentile higher because it

provides no disadvantage whatsoever in overall health and performance that's going to look like something like north of 22 for men and north of 18.1 for women of course if you're extremely ambiguous and you want to challenge Ray Williams and his record of 41 by all means to be my guest

and please report back to me if you've accomplished such a feat. FFMI is not an intuitive number or score so if I were to give you an FFMI score that puts you in the 75th percentile you wouldn't really know what that means so let me explain to you how that number is calculated and run you through a

couple of samples and I'll do it both in the empirical as well as in the metric units. Now we know science works in kilos so we will start there globally when we think about body composition we're thinking about how much muscle do I have versus how much fat but as I said it's actually

a little more complicated than that so if you were to get something like a dexascandone or even stepped on a scale and that gave you your body fat percentage what is telling you is what percentage of your overall body weight is fat versus what is lean body mass and remember that lean mass is not

just skeletal muscle it is skeletal muscle plus bone and water and things like that so as a sample calculation let's try this let's say you were five foot ten and weighed a hundred kilos now I'm picking a hundred kilos because it makes a math very easy and for many of you listening you're

going to appreciate the fact that I've made the math somewhat simple for you so if I were to be a hundred kilos in weight and my body fat percentage was 25 that means 25 of those kilos are fat and 75 are non-fat as I said earlier most people that are decently trained anyways of their lean

body mass somewhere between 45 to 50 percent of that is actual skeletal muscle and so we're free to take that 75 divide that by two assuming 50 percent this would mean you probably have something like 37.5 kilograms of actual muscle in your body and again 25 kilos of fat if you

want to calculate your FFM my score from there all you would have to do is go back that lean body mass number so in kilograms so in this case 75 and divide that by your height so how tall you are in meters squared so if you're a five foot ten inches tall this is 70 inches which would be about

1.778 meters so you take 1.778 square that and then you take 75 and divide it by that number this would produce in this particular case an FFM my score of 23.7 pretty decent overall you can also intuit if you look at somebody who's five foot ten they're two or the hundred kilos and 25

percent body fat this is an individual with a lot of muscle mass and so this probably makes sense that they'd be on the upper end of the spectrum I'll run through that exact same thing now in pounds for those of you that prefer that method so a hundred kilos would be 220 pounds so just

take the kilos multiply it by 2.2 if you were to run the exact same equation so again assuming 25 percent body fat this would leave you with 165 pounds of lean body mass and 55 pounds of fat mass take that 165 again let's assume 50 percent so we'll divide that by two and you would have 82 and a

half pounds of lean mass but unless we'll go back up and you would take that 165 pound number you would need then to convert that to kilograms which means you divide it by 2.2 which would put you right back into that 75 kilogram number take that divide that by the same units in meters

squared of your height and that would give you that same exact FFM my score so very easy to convert your body weight in pounds to kilos convert your height in inches to centimeters and then convert that to meters go online Google conversion it'll do it in two seconds for you and you're able to

quickly calculate your FFMI our third eye of intervene which is a fancy way of saying what interventions do I do what stimuli do I introduce to aid and muscle growth now I'm not really going to discuss muscle loss I don't really see any advantage to doing that so we'll focus on simply

augmenting or increasing muscle mass a couple things to get you started while nutrition is an important consideration here I need to make sure that it's completely clear here resistance sector size is by far the greater stimuli of muscle growth relative to nutrition really from

this perspective we need to make sure we have sufficient calories which is to be said as hyperchloric so we need a little bit more calories and we're burning to this day alive and mostly we need to focus on protein here 1.6 grams per kilogram of body weight is a great place to start now I personally

prefer a little bit higher 2.2 grams per kilogram which is about 1 gram per pound but actually I believe the science is pretty clear here suggesting that going from 1.6 to 2.2 is not really going to increase the amount of muscle you're you're growing and if it is it's not going to be by much

and so if you prefer to be at 1.6 that's fine higher is absolutely okay as well and it may aid in some people in some circumstances but going below 1.6 seems to reduce the amount of muscle you can grow so we want to be at least that number from a training perspective you want to start by focusing

on your big muscle groups now if you have a particular muscle or group of muscles that you want to increase for any number of reasons say you've identified an asymmetry have a personal preference you enjoy that more you just want to have a muscle group grow larger for some aesthetic reasons

that's absolutely fine focus on those but you really shouldn't omit everything else either it's critically important to maintain posture and joint integrity by ensuring we have adequate muscle surrounding each joint which basically means we need to address each muscle at some point

throughout the week we can certainly emphasize some more than others that's no problem whatsoever but we don't want to leave big chunks of muscles completely unchallenged that's going to present problems more likely if not now down the road so we also want to challenge these muscles

across multiple stimuli meaning exercises so whether you prefer your body weight machines dumbbells kettlebells or any number of other strategies those are absolutely fine all are incredibly effective and at the highest level it actually doesn't really matter that much

which of those strategies you try because at the end of the day it's just about stimulating the muscle however you go about that is absolutely fine so you have lots of options there perhaps in a future episode we'll get into the the details and spend the entire discussion on that going over

pros and cons of those different strategies and tactics but for now at the again the most zoomed out level you've got a tremendous amount of options regarding which exercise you select and which modes and methodologies you do to engage in that resistance exercise the range of motion is

critical you want to use the largest range of motion you can while still being safe and protective of both the exercising joint as well as the joint above it and below it so an example here let's just say you're interested in growing your quadriceps you want to have a lot of activity

over both the knee and hip joint but you want to make sure that you're doing though that in a case in which you're not compromising your low back and say your feet and so making sure we're protecting the joints above and below the muscle group is important as well so we really want to challenge our

muscles as much as we can in a variety of ways there in terms of how much to do the repetitions per set doesn't really matter such that you can have success in a number of them anywhere between safe as low as five repetitions per set all the way up to 30 or more repetitions per set can be

equally effective for muscle growth the total amount of sets per week is probably the bigger determinant from there you probably want to be in the neighborhood of about 15 to 20 working sets per muscle per week if you're to break that down let's say you were focusing again on your hamstrings muscles if you did three sets on day one three sets on day two and three sets on day three that would give you a total of nine working sets per week that's probably a little bit too low but if you did

two hamstring exercises each day three sets each that'd be six sets day one six sets day two six sets day three and now you're up to close to 18 working sets per month per week rather that's a pretty good spot to be in lots of things we could talk about there in terms of advanced athletes and

leap but structurally and roughly that's going to put you in the ballpark that's going to be enough stimulus for most people to grow most of the time last consideration here is frequency as I sort of alluded to here somewhere between two to three days per week per muscle group is a great way to go

about it more as fine as well if you can handle the recovery less than two days a week is also theoretically possible there's excellent research showing one day a week per muscle group is sufficient to most

to grow muscle it does become practically challenging though because now you've got to fit all those working sets into a single day and that is challenging both in the length of the workout as well as how sore and how much damage you create so what I recommend here is what I call the 72 hour rule

which is every 72 hours or so work each of your muscles to a nice pumper contraction remember we want to stimulate muscle growth here but we don't want to annihilate the muscle either excessive fatigue and damage and soreness does not aid and muscle growth and can actually harm our ability to

come back and train again in the next session or even the one following that which would then reduce our overall total volume so enough intensity enough difficulty to stimulate growth but not so much that we completely annihilate it we got to we got to be able to repeat that every 72 hours or so

so again the way I say it take it to a nice pump a nice contraction whatever that means to you and that's going to get a lot of people in a close enough ballpark to growing muscle I'd like to take a quick break and thank our sponsors today's episode is brought to you by Maui Nui Venison

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slash perform to save up to 50 dollars off of your subscription again that's rpstrength.com slash perform to save up to 50 dollars off your subscription so now that you have a better understanding of how to identify and interpret and then modify the amount of muscle you have

let's now talk about the quality of muscle this is not as straightforward I can't give you a simple equation or run you through a quick math problem because quality means different things to different people in different scenarios so rather than try to give you an exhaustive list of all of them

I'll start with just a couple of examples and let you infer on past that the first thing to consider here is really not specific contractile properties of an individual muscle but collectively how you move now I'm not going to get into this fully but really quickly it's important to understand

how an individual moves the quality of that which muscles are using for which muscle group their technique how that is portrayed across the joint is important for all of us again whether we're in a sporting context or just general life and so when I'm thinking about yeah how much

muscle do I have and then also what's the quality of that muscle I need to be thinking about how that muscle is actually used as a simple explanation here I look for four basic things when determining successfulness of human movement if you're in a specific sporting context you're of course going to

add your own unique flavor so how I made it like baseball picture moves is going to be quite different than even somebody like a golfer who are both in rotational asymmetrical sports how they move you can expand that even beyond that to somebody like an NBA player or a pickle baller all of these

coaches and athletes in the individual sports are going to want to have different muscles move in different fashions in different sequences I can't get into all those details now so just stepping back and thinking globally what are the core principles that are true in all those

examples to me it's really four basic elements the very first one is range of motion are you able to go through a range of motion in all of your joints that is appropriate for those joints as an example your elbow is meant to flex and extend it can rotate internally and externally this so

to imagine taking your palm of your hand and sticking it up in the air and then taking the palm of your hand and sticking it towards the ground internal and external rotation however your elbows not meant to bend left and right if you want to move your hand in closer to your body or away from your

body you actually have movement of your shoulder joint and so an elbow has a few ranges of motion a shoulder though can go up and down and front and back it can rotate and kind of roll itself internally and so each joint has a different range of motion it can go through so can you go through

all those range of motions in a way that's appropriate without being too much range of motion the second thing we want to pay attention to here is rough symmetry like we've talked about a couple of times already so symmetry means again am I okay moving front and back within one joint or

groups of muscles and then how does that compare to the contralateral or opposite side so if I can lift my say right shoulder straight out in front of me and I can lift it all the way over my heads that it's pointing directly in the sky but my left shoulder can only go 80% of the way then I

have some sort of asymmetry is it the front and back so my shoulder on the front side of it is twice the size of the back side of it things like that so we want to look at do I have global asymmetry especially when we're doing what is called bilateral movements so imagine doing like a squat

picture a basic air squat or a goblet squat where you're holding an implement in front of you or you're squatting down like you would do to hold a child or a baby or something like that in doing that I would want to be looking at all of my joints and I would do this one by one so

starting at the ankle joint I would say okay great can my ankles go through a full range of motion or they restricted and then that we're causing a movement compensation at the knee or hip or some other joint are they symmetrical is one facing a different direction than the other one does one

have more range of motion than the other one etc etc so that's just one example of how we would look at the range of motion and symmetry within one joint the third thing we want to look at is stability let's imagine that same squatting movement so I want to look at now say my knee I'm

going to ask the same thing can my knee go through a full range of motion is it symmetrical so is the left knee doing the same thing that the right knee is doing and then thirdly now is it stable so is the joint able to go up and down under control without excessive wobbling or shaking or any

other movement pattern that I'm not intending to do to me that's stability really you're talking now a combination of motor control and strength but we can globally think of that as is the joint stable when I'm asking it to be stable human movement is really two things it is asking a joint

or muscle or muscle groups to move in a way that we want and also at the same time not move in ways that we don't want both of those are critical to moving well the third and final element here is simple awareness so is the individual aware of what their joint is doing a lot of times movement

dysfunction like this is simply somebody not knowing their foot is not supposed to point in that direction somebody not realizing that one side is aimed at another direction than the other side so simply people letting people know that their joint is not supposed to be doing that that's not

a proper pattern is a critical component so from the onset and again we can maybe have further discussions about this in future episodes moving well needs to have those four components at each joint throughout our body if we can do that we can set aside the injury risk and stuff and again

talk about that later and we can move on to really performance now when I'm asking about a muscle or muscle groups to perform I cared about three things can it be fast can it be strong and can it have what's called muscular endurance this can be expressed over a concentric muscle action

an eccentric or an isometric so generally when we say concentric we're thinking about shortening of the muscle length so imagine doing a biceps curl when you're actually taking the the dumbbell and moving it closer towards your shoulder or your face that muscle or muscle group is shortening

that'd be the concentric portion if you got all the way to the top or say halfway up or any range part of the range of motion and you stop the movement and held it there that'd be isometric and then if you lengthen that back down all the way to the bottom that would be the eccentric

portion of it and so I want you to have the ability to be fast and any of those ranges of motion or any of those muscle actions I want it to be able to be strong any of those muscle actions and then I want it to have the ability to repeat that multiple times this could mean repeating

holding the position so if I could go to say halfway up I could flex and hold it there I want to be able to hold it for as long as I need based on the specific muscle or the movement I'm trying to do or be able to perform multiple repetitions if we're looking at basically any style of human movement

it's going to need to be fast it's going to have to be strong and it has to display some semblance of muscular nerves so if I summarize all of this the way to investigate whether or not you have sufficient muscle quality has two unique parts part one is understanding do you move well

now that definition of move well really changes depending on the sport or the context the way that your hamstrings need to contract for a hundred meter sprinter are quite different than somebody who wants to just be able to hike all day or across country skier or anything else so that is context

specific but I gave you an example of four things that are generally pretty universal regardless your muscles need to go through an appropriate motion they need to be symmetrical they need to be stable and you need to be aware of what they're doing if you're aware of the context say you have

a specific sporting outcome then you can lean on a coach or an individual in that area if not there are plenty of global movement screening tools so these are different tests you can do that allow you to understand a basic human movement pattern many of them to choose from it could

probably put some in the show links for you there are some nuances within plenty of them but something like that should be chosen you have a lot of options I would strongly recommend though picking at least one thing from the how do I move column in order to investigate

is your muscle functioning appropriately the second thing then is some sort of performance metric so this could be something simple like a leg press machine or more complex like a single leg squat or anywhere in between and within that you want to identify whether or not the muscle is capable

of moving fast moving strong and can repeat that performance over multiple repetitions helping you interpret your score on a movement screen is really challenging without having a lot more individual context so what I like to do is give you some more straightforward and specific

examples from the metrics of speed power and strength in sticking with the theme of the show I want to give you some context as to what the best in the history of the world look like for muscle speed power and strength and my opinion no one typifies muscle speed more so than a hundred meter

sprinters this is the quintessential best test in the world of maximum velocity and so when we look at the best two names jump off the chart of course from the female perspective this is flow Joe the American sprinter and then from the male perspective no one comes close to you saying

bold so how fast were these two individuals well a little bit of context here it took about 40 years and 11 individual men to drop the world record in the 100 meter dash by about two tens of a second from 9.95 to 9.74 both did nearly the same thing all by himself he dropped the world record

by 0.16 seconds all the way down to 9.58 seconds over the course of his career so he himself represented almost the same progress is the entire field made in 40 years that's how much faster he was than anybody else ever before him and still to this day no one's come even close to matching that

feet in fact only two people ever have run a hundred meter dashed in under 9.7 seconds which means you saying bolt is over a tenth of a second faster than anyone ever in the history of the competition now there's actually a lot of interesting people who tried to understand and examine

why he's so much faster than anyone else there was an interesting paper that was entirely speculative was not from his team but some biomechanics researchers tried to figure out what would be possible for him to do that and the best that they could estimate was that his fast twitch fibers which

we talked about earlier in the show are about 17% faster than other world class caliber sprinters again this is entirely speculation we don't know if that's true there's no data or evidence of biopsies that's public record of you saying both although I've been on record for many many times saying

I would love to take that biopsy if you're listening you say but of course some of the magic that goes into sports performance is we don't always get to know why people are how they are now something else I find extremely interesting about this is what happens to maximum speed as we age and the

reason I'm drawn this out is we talked earlier about how preserving these fast twitch muscle fibers is critically important and if you look across world records as we age in speed activities versus strength versus endurance a clear pattern emerges people drop maximum speed capability way faster

as they age then they drew strength and then certainly endurance in fact the world records in most endurance based activities really don't change from folks who are 35 years old to 40 or so and when they start dropping at 45 to 50 plus it is fairly small until we get to advanced stage speed

on the other hand falls off a cliff almost immediately as an example I told you you saying bolts record is a second ago 9.58 seconds if you go to the first age category which is 35 years old the world record jumps up to 9.87 seconds and that's just at 35 years old if you're in endurance

sport that actually might be in your actual prime still it gets even further faster as we go to 40 years old that record jumps to 9.93 and then at 45 it is a whopping 10.7 seconds so you're talking about now addition of well over a second by just going to the age of 45 to this date I'm not

aware of any human ever running 100 meter dash in under 10 seconds over the age of 40 years old so extraordinarily challenging as we go on just to rattle off a few additional numbers every five years or so you add on to age you're going to look at additional half a second or so

increase in your 40 yard dash time for those of you that are curious the world record for a 100 year old male is 26.99 seconds in fact the highest number I've seen was just a few years ago a 105 year old ran a 34.5 second 100 meter dash so I'm not sure where you're at you're welcome to go

out and time yourself on this please don't tear your hamstring maybe warm up and try it a few times before you go full maximum speed but I hope most of you can come in under that 34.5 seconds if not rest assured there's 105 year old out there somewhere who will beat you in a 100 meter

sprint and that's embarrassing coming back to the female side foreign scripted joiner or flow Joe as I referred to her earlier still holds the world record at a time of 10.49 seconds and to give you a little bit of context of how dominant that was it is still the record some decades later

and I believe there's only one other female to ever run below a 10.6 so tremendous speed on her part we can play the same game here as age goes on although it is a little bit less dramatic than the men the world record for 35 year old is held by a still current and competing star shelly and

phrasier price at 10.62 seconds as you go up to the 40 year old you're talking about now again a similar half a second or so jump to 11.09 seconds and then it continues really on from there all the way to the end there you've got a 100 year old coming in at a smoking 39.62 seconds and then of

course a 105 year old a little bit slower at a time of one minute and 2.95 seconds so as I mentioned if you're a woman out there and you can't run a 100 yard dash and under a minute again there's 105 year old out there who will smoke you running 100 meters as fast as you can may not be the best

test for many of you out there and so while I think that speed is critically important and it is different than power many of you could probably get away with just a simple test of power and you have a lot of options that are more realistic and probably a little safer for many of you if you're

an athlete or competitor of some type a lot of ways you can go about this of course you can use things like a force plate which is an incredibly expensive and fancy scale that can tell you exactly how much force and how much time it takes you to push into the ground other options are just simply

doing something like a vertical jump test or a broad jump test a very very easy rule of thumb that I like for the broad jump and this is again a horizontal jump so how far out in front of yourself can you jump is can you jump your height so if you're six feet tall can you jump six feet

high level athletes are going to be looking more like nine to ten or even 11 feet in that jump but a basic metric for the average person is can you jump your height vertical jump is actually my favorite way you can do this easily with just a tape measure you know put put a mark on the wall tape how high you can jump measure it that way as far as I know and actually I checked around with a bunch of colleagues on this there's no scientifically verified high world record for this Guinness has

their own records scientific publications a little bit different and so I actually called a friend of mine Paul Fabrice Paul is a world renowned basketball trainer has coached and worked with some of the best basketball players in the world and I asked him and he told me basically in his opinion

48 inches or so is the highest he's ever seen this would be a standing vertical jump if you were to get an approach say maybe two or three steps to run in you might be able to jump into the low 50s but he doesn't really think anybody has eclipsed the 50 inch mark in terms of a standing

vertical jump there's not extensive evidence on vertical jump height by age and so that's a little bit more challenging to give you so what I would say is again focus on something more like that broad jump test another option is to use machines like a proteus now you may have this available

depending on where you train at your local gym or clinic somewhere and these are machines that allow you to test your power in a number of different planes and this is really interesting because companies like this are starting to collect normative data on average people for power testing and I

don't have anything like that to report to you right now and so what's going to be hopefully interesting in the coming years as they start to release and publish these results I will have normative values based on age and sex for things that are not just vertical jump base not all of you

can do that you may have say ankle knee or back injuries I don't allow that or it's not realistic or for some other reason and so being able to identify and test your power and things like rotation and vertical movements that don't require jumping and landing are things that I hopefully

am able to share with you in the coming years once those data become available now technically the highest power output seen in the literature come from weightlifting or what's more effectively known as Olympic weightlifting so both the athletes themselves as well as the movements so the

snatch clean and the jerk and variations of this produce extraordinary amounts of power the problem is if you're not extremely technically sufficient in these activities you can't really test your power with them because you'll be limited so much by your technique we won't get a true expression

of your power so if you're familiar with those movements they are a fantastic way to globally test your power if not you might want to opt for something more like that vertical or broad jump test so to round us out here let's talk about strength there's a lot of different things I can pull up here

but the most direct plane measure of absolute strength comes from the sport of power lifting now not to be confused with Olympic lifting this is the sport of a one repetition maximum in the deadlift bench press and back squat there's a lot of different federations and rules and

all that and so to not bog down and unnecessary information I'm going to give you the numbers that represent what's called the equipped category which is to say the highest amount equipment possible what's just the most amount somebody's ever lifted there are subcategories like raw which

says you can't have certain equipment like belts and wraps and straps and special shirts and things like that you could debate whether or not you find one more relevant or interesting the other one I don't really care I just want to share with you the most amount ever lifted any human without

some arbitrary rule that these organizations have set now in power lifting you get to find your one repetition maximum among those three exercises and you can also combine them together to get a total so from the men's perspective there have only been two ever to cross a three thousand pound barrier

such that between the three exercises squat deadlift and bench they totaled more than three thousand pounds the two gentlemen Donnie Thompson and Dave Hoff Hoff having the current world record at three thousand one hundred and three pounds now my longtime friend AJ Roberts actually might have a

better resume here he totaled two thousand eight hundred and fifty five pounds but did it at probably thirty or fifty or so pounds lower than these other two gentlemen I'll let them all figure that out but nonetheless almost three thousand pounds across three different exercises

if you want to go through the exercises individually we have different people with world records there so the squat right now current world record is from Nathan Baptist at an astounding thirteen hundred and eleven pounds again friends you heard that right this is a thirteen hundred

pound back squat from the bench press was this was actually just recently broken Jimmy Colbe did this and this is this is unbelievable the world record is now thirteen hundred and fifty pounds the previous world record he broke by almost two hundred pounds I don't know if this is more

impressive than you say in bolt but hard to argue when you beat a world record by an additional two hundred pounds like simply unbelievable that strength accomplishment another actually fun thing to know here is I believe fifth or six on that list is a gentleman they bill Gillespie

at a total of eleven hundred and twenty nine pounds he actually also did this pretty recently and the fun part about bill is two things one he's sixty two years old you heard that right sixty two years old and just I think last year bench pressed well over eleven hundred pounds the other

thing interesting about bill is he was actually one of my first mentors when I was an undergraduate student bill was the head strength edition coach of the university of Washington I'm from that area and so I was fortunate enough to beg bill to let me come up and shout out him one day and he said

fine you can do that but I'm training and so I showed up there probably thirty minutes late was beyond embarrassed to thought don't even go in go home this is so ridiculous that you showed up this late for a guy like that he was the kindest sweetest guy ever put in his mouthpiece had

his training logs out there and proceeded to do one of the most impressive training sessions I've ever seen while giving me guidance of being a strength edition coach I'll also never forget bill looked at me now in context you can imagine what bill looks like at the time myself I'm

a five foot eight probably a hundred and eighty pounds at the time college football player but still incredibly small compared to him and I will never forget the words he said to me it made a huge impact on my life I asked him about being a collegiate strength edition in coaches I

thought this is what I wanted to do with my life and he looked at me straightly and directly and said you're a dime a dozen you don't matter and he didn't say it with hate or hurt at all it was the kindest most direct and helpful thing I've ever heard it changed the trajectory of my life

and it made me realize if I wanted to make it as a strength edition coach I was going to have to do a lot more than to just show up with my exercise history the third and final exercise that deadlift was set by the famous Andy Bolton who I believe is the only person still to the state to ever

deadlift more than a thousand pounds at a thousand and eight now from the female side of the equation you have some equally impressive if not more impressive numbers the world record total there's only been two women ever to cross the two thousand pound barrier that'll be Becca Swanson and Leah

rightman Swanson currently owns that record at two thousand and fifty pounds the individual records the squat Leah holds that record at nine hundred and twenty five pounds I don't know when she's gonna cross a thousand but I keep watching to see when it's gonna happen that would be just absolutely insane to see and good luck to you Leah on that one the bench press re-en miller currently holds that record at six hundred and fifty pounds and then the deadlift is currently set by Becca Swanson at

six hundred and ninety four pounds so now that you know what that gold standard really is for strength what are some more realistic numbers for the average person for men I like to see about a one-to-one ratio for the bench press such that you should be able to bench press your body weight so a two hundred pound person should be aiming for something like two hundred pound bench press for women it's about

point six upper body strength is significantly less in women in general and so you're gonna have to scale that down a little bit more now for the back squat it's hard to give you numbers because it is so technically demanding I think it's easier to give you something more like a leg press value

for men you want to shoot for something like double body weight and for women something like one and a half times or so so that hopefully gives you a little bit of context of the numbers to go after last thing I want to add here is actually something we'll talk about a lot more in the future

and that is grip strength is incredibly important and a great insight into your overall health for both athletes and non-athletes easy to test there's a number of ways that you can grab hand grip dynamometers they're cheap and available almost anywhere for men just again a rough number here

I'd like to see individuals over 45 kilograms and then for women over 28 kilograms or so another thing to keep in mind here is asymmetry really matters now this is the first test I've given you where you can isolate you know your left side from your right side really important to test your

grip strength in bull recent papers have come out suggesting that an asymmetry of more than 10% specifically increases your risks of sarcopenium and heightened denervation of muscle groups by 2.67 fold and so we'll talk about that more in detail later but really really important you want

to understand whether or not you have major asymmetries in strength between both your sides again some asymmetry is probably okay maybe even advantageous for some sporting applications but asymmetries outside of that are potentially concerning if you're unfamiliar with that term

sarcopenium describes the the excessive loss of muscle mass with age we know there's going to be some sort of natural decline in the amount of muscle mass you have in fact unruff average men will lose about 40% of their muscle mass from the ages of 25 to 80 so we know it's going

to happen we've talked about how strength training and our adequate nutrition can reduce that loss of muscle but some of it's going to happen so sarcopenia really refers to the excessive or additional loss of muscle beyond the normal loss with aging so those strength standards I gave you are rough

guidelines but I want you to get as strong as possible I don't necessarily need you to be squatting or benching 13 hundred pounds but I don't want you to stop at body weight either so outside of of course leading to injury and getting hurt which is something we don't want to do there's no

disadvantage to getting stronger I've tried to make that argument with muscle mass earlier in the show but I can really make that heavily with strength in fact if you were to compare the two muscle mass the muscle strength muscle strength is by far a stronger predictor of both how long

you're going to live as well as how well you will live within those years that's number one number two getting stronger only continues to reduce your risk of developing things like sarcopenia or late onset dementia in fact one particular study of note here this study had around

500 thousand or so individuals pulled from the UK biobank which is a similar setup as what we've got here in America that I talked about earlier in our NHANES database now they study these individuals across nine years and during that time around 4,000 or so the individuals developed

dementia and so what's interesting is they're able to go back and say okay what unique characteristics existed prior to the dementia as well as after the onset and how did that compare the individuals who didn't have the dementia set in and this one certain study and just one study so we want to be

cautious of overinterpreting here what they found was 30% of the dementia cases were attributed to having low grip strength and this was independent of a number of other important confounders we will talk about these things more in future episodes and I don't want you to get overly concerned with

that specific result or those specific numbers I just wanted to highlight though the critical importance of getting stronger really helps overall global health and what's furthermore interesting about this paper and many many many others is there doesn't seem to be an upper limit

so when you continue to increase strength you continue to reduce risk of all cosmortality dementia and similar other things and so we don't see this really even an asymptote we don't see a tapering off of benefit we just continue to see rises and improvements in risk reduction factors

hazard risk mortality risk and number of other things important to overall health when we continue to get stronger whether we're talking about grip strength leg strength or anything else and so it just right now according to the data across again multiple areas just continuing to get stronger

seems to continually benefit human health and performance at this point we can now move into our final eye which is intervene in other words what do you do to improve your muscle quality I'm going to give you four big areas to focus on the very first one is similar to what we talked

about for muscle quantity and that is you want to train all of your joints through all the range of the motion one thing people fail to realize is it's good to be strong but you need to be strong and fast and have good endurance over the entire range of the motion you're going to be put

into positions likely where the muscle needs to contract when it's shortened when it's extended and many other positions and so we want to train that somehow across multiple range of motion the first is similar to what we talked about with muscle quantity and that is all ranges of motion

you want to be strong fast and have great endurance when your muscles are both shortened when they're extended and when they're in various positions as always we don't ever want to put a joint into a bad position and then we definitely don't want to load that or contract that but as much as we can

we want a force human movement and a high quality through a large range of motion the second one here is being intentional so where this differs then say the muscle size issue is muscle quality is about eliciting an improvement in human movement whether this means we're more efficient whether

we're producing more power or speed we've got to move in a certain way and so now we're talking about a quality that extends outside of the muscle itself and into a human movement and so we want to be incredibly intentional about how we're moving our technique our rhythm our timing our tempo

what should be moving what should be relaxed what should be contracting is all critically important to moving better if you ask any sprinting coach they're going to talk about things like rhythm and timing and tempo and what they're really talking about is this stuff how this applies to

everyone else is simply understanding when i'm trying to contract same my pecs or my shoulders for bench press what should my glutes be doing should they be contracted all the way should they be totally off and relaxed should they be halfway things like that so paying attention to your

movement quality is the fastest way for most people to actually move faster and move stronger improve technique first and then chase after improving maximal capacity of the actual muscle fiber and tissue the third is in making sure you're balancing movement planes and posture

so if you want to get a better squat make sure that your glutes aren't significantly stronger than your hamstrings or that your adductors and your your groin and then the muscles that kind of pull your knees together aren't significantly weaker you will only ever be as strong as fast as your

weakest link in that movement chain so ensuring you don't have anything grossly behind something else and that you're training yourself so that the muscles move appropriately think about it this way there are some muscles and joints that are meant to be stable and others that are meant to be

movers and they tend to stack in an every other one fashion such as this i gave the examples of the knee and the hip earlier the ankle is meant to be highly mobile and move a lot the knee is meant to be stable so if the knee is stable this allows the ankle to move a lot and then the opposite

direction would be the hip so you want a highly mobile hip a highly stable knee so you can have a highly mobile foot going above that since the hips are mobile you want the low back and the lumbar spine to be stable so that the thoracic and kind of mid back spine can be mobile so that your shoulder

joints and your neck can be stable this allows then the shoulders to be mobile the elbows to be stable and the wrist to be nice and mobile now it is more complicated than that but really at the highest level that is a nice summary of how the muscle actions are supposed to work if you think about that in general contacts it's going to keep you pretty safe and it's going to allow you to move well lastly then is what i call the three to five rule so the three to five rule applies to strength

power and speed what it roughly means is is choose three to five exercises do three to five repetitions for three to five sets rest for three to five minutes in between each set and repeat that three to five times per week so at the lowest level this could mean three sets of three repetitions three

days a week of three exercises this would be a pretty low volume but because of that that would allow you to go really really heavy or to really high intensity you're going to have a lot of recovery not going to stimulate a lot of muscle growth won't stimulate hardly any muscular endurance

that could be used if you're trying to maximize the recoverability or the strength aspect going higher on that spectrum say five sets of five of five exercises five days a week would get closer to the high perch for your muscle growth into the spectrum would give you a little bit more muscular

endurance and would be a lot more volume for those individuals or a higher training status for muscular endurance you can add any number of things number more repetitions per set more sets less recovery in between sets or anything else like that training do a little bit of fatigue is a

pretty easy way to think about muscular endurance of course exercise science is an entire scientific field it gets far more complicated than that but that is a rough idea of how to intervene to change the quality of contraction of which your muscles can go through so to wrap everything up today we

talked a lot about skeletal muscle we went over how it actually works what it's made of why in my opinion it is the most important organ in the entire body and deserves more credit and attention we talked about why you want to make sure that it is functioning at the highest level possible

this means both a quality of muscle functionality contractile properties how much force sick and produce how fast it is and other things like that as well as the quantity of how much muscle you have in general we went into a little bit of the micronatomy so the difference between fast

twitch fibers and so to true fibers and why it's important that you pay particular attention to high force activities in order to preserve those fast twitch fibers regardless of whether or not you're an athlete or a person interested just in longevity and overall wellness so from there we

talked about the three eyes the first being investigate so identifying whether or not you have enough muscle and how it's functioning in terms of power and speed and so on the next eye of course was interpretation so letting you know whether the amount of muscle and the strength and power you

have is good great close to some of our world records whether you're male or female or maybe not quite as high as you think and then lastly to intervene so what do you do about it what are some protocols and things you need to do it from a lifestyle perspective to improve the both muscle

quality and quantity I hope you found this initial discussion of skeletal muscle interesting and useful now when I say initial that's for a reason I have a lot more to tell you about skeletal muscle but we're going to have to save that for future episodes thank you for joining for today's

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you have to say I use my Instagram and Twitter also exclusively for scientific communication so those are great places to follow along for more learning my handle is doctor Andy Galpin on both platforms thank you for listening I never forget in the famous words of Bill Bauerman if you have a body you're an athlete