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This podcast is going to cover a technical aspect of muscle building. I’m discussing which is more important for getting bigger and stronger: hypertrophy or hyperplasia?

What do those words even mean?

Well, hypertrophy is when your muscle cells get bigger, and hyperplasia is when the number of muscle cells increases.

Scientists aren’t sure whether hyperplasia even happens in humans, but “believers” contend that both hypertrophy and hyperplasia contribute to muscle growth. Thus, according to them, you should train to produce both of these phenomena to gain muscle as quickly as possible.

Focusing on hypertrophy or hyperplasia would change how you train, so this topic has practical applications I’m going to break down for you in this podcast.

Lastly, if you want to support the show, please drop a quick review of it over on iTunes. It really helps! 


4:27 – What is hypertrophy?

4:46 – What are the components of muscle?

4:56 – What is myofibrilar hypertrophy?

5:16 – What is muscle hyperplasia?

5:37 – Does hyperplasia happen in humans?

7:16 – Does hyperplasia exist?

8:10 – How do you induce hyperplasia in animals?

9:26 – What does the science say about hyperplasia in humans?

16:56 – How do we cause hypertrophy?

18:28 – Why does training near failure produce hypertrophy?

19:06 – What about hyperplasia and training?

20:12 – Does stretching cause hyperplasia?

Mentioned on the Show:

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Oh, hi there, and welcome to another episode of Muscle for Life. I am Mike Matthews. Thank you for joining me today. And before we tear into today’s discussion, take a moment and subscribe to the show if you like it. If you’re not sure if you like it yet, maybe. You will want to subscribe after this episode, but if you already know you like the podcast, subscribe to it in whatever app you are listening to so you don’t miss any future episodes.

And it helps me because it boosts the ranking of the show and the various charts, and then more people can find me in my work. So today’s episode is going to be about muscle building, and it’s going to be about a technical aspect of muscle building. It is hypertrophy versus hyperplasia. Which one is more important for getting bigger and stronger?

Now, what the heck do these words mean? It’s pretty simple. Hypertrophy. Occurs when muscle cells get bigger and hyperplasia occurs when the number of muscle cells gets bigger and countless studies show that hypertrophy occurs in humans normally as a result of resistance training, But hyperplasia is not so cut and dried.

Scientists aren’t even sure. Whether it exists in humans or not, whether it happens now, the believers, the true believers, they contend that hypertrophy and hyperplasia both contribute to muscle growth. And if you want to get as big as you possibly can, or if you just want to gain muscle as quickly as you possibly can, you should train to produce both of these phenomena.

And if. To primarily produce hypertrophy, then you are going to train differently than if you want to primarily produce hyperplasia. And so this topic is not just merely academically interesting, it also has practical implications. And I’m gonna break it down for you in this podcast. Also, if you like what I’m doing here on the podcast and elsewhere, definitely check out my v i p one-on-one coaching service because my team and I have helped people of all ages and all circumstances lose fat, build muscle, and get into the best shape of their life faster than they ever thought possible.

And we can do the same for. We make getting fitter, leaner, and stronger, paint by numbers simple, by carefully managing every aspect of your training and your diet for you. Basically, we take out all of the guesswork, so all you have to do is follow the plan and watch your body change day after day, week after week, and month after month.

What’s more, we’ve found that people are often missing just one or two crucial pieces of the puzzle, and I’d bet a shiny shackle, it’s the same with you. You’re probably doing a lot of things right, but dollars to donuts, there’s something you’re not doing correctly or at all that’s giving you the most grief.

Maybe it’s your calories or your macros. Maybe it’s your. Selection. Maybe it’s your food choices. Maybe you’re not progressively overloading your muscles, or maybe it’s something else, and whatever it is, here’s what’s important. Once you identify those one or two things you’re missing once you figure it out.

That’s when everything finally clicks, that’s when you start making serious progress. And that’s exactly what we do for our clients. To learn more, head over to That’s by, and schedule your free consultation call, which by the way is not a high pressure sales call. It’s really just.

Discovery call where we get to know you better and see if you’re a good fit for the service. And if you’re not for any reason, we will be able to share resources that’ll point you in the right direction. So again, if you appreciate my work and if you want to see more of it, and if you also want to finally stop spinning your wheels and make more progress in the next few months than you did in the last few years, check out my VIP coaching [email protected]

Slash V I p. Okay, so let’s start this discussion with a reiteration of the definition of the terms in case you skipped the intro, which is totally fine. So hypertrophy is the scientific term for an increase in muscle cell size. So hyper means over or more, and trophy means growth. So hypertrophy literally means the growth of muscle cells and technically muscle hypertrophy can be achieved by increasing any of the three.

Components of muscle tissue. You have water, glycogen, and protein. So if you increase any of those things, hypertrophy has occurred. And those of us who like to bang weights, we are normally most interested in increasing the amount of protein. In muscle cells, and that’s known as myo fibular hypertrophy, as opposed to the fluid components, which is sarcoplasmic hypertrophy.

Although both of those things though, they do contribute to muscle size. Now, muscle hyperplasia refers to the formation of new muscle cells, and plasia simply means growth. So by increasing the number of muscle cells, In a muscle, of course, that would increase its size in the same way that just increasing the size of the existing muscle cells would, and research shows that there’s no doubt about muscle hypertrophy that occurs in humans, and that contributes to overall muscle size and muscle growth.

But, Muscle hyperplasia in humans is dubious. Many people say it does not occur at all, and any increase in muscle size is solely from an increase in the size of the individual muscle fibers that we already have, or muscle hypertrophy. Now, why does this matter? If those people are wrong, if the muscle hyperplasia naysayers are wrong and the muscle hyperplasia advocates are right, then if you are not doing certain things to maximize muscle hyperplasia, if you are really just focusing on hypertrophy, then you are only gonna get so far in your journey.

You are only gonna get so big and strong. But if you. Do a lot of hypertrophy work, as well as a lot of hyperplasia work. And if you combine them in the right ways, the legend goes, then you can break through that ceiling, that hypertrophy ceiling by adding new muscle cells that you can then make bigger.

Because you can only make a muscle cell so big and the muscle cells that you have are only going to get so big before they just stop responding to. Any sort of stimulus by getting bigger. And at that point then of course, the only way to continue getting bigger, again, this is the theory, would be to add new muscle cells.

Now, there’s no question that hyperplasia exists. Many studies have confirmed the existence of this. Phenomenon in different animals. It’s been shown in quails, in chickens, in rats, mice, rats, cats, fish. And many people say that, Hey, if it is occurring in all of these different animals, there’s. A reason to believe that it is also occurring in humans or that it can occur in humans because while we don’t look like any of these animals, we do share a lot of DNA and a lot of physiological systems in a mouse, for example, work similarly to the.

Counterparts in humans. And so scientists for some time now have believed that hyperplasia is something worth investigating in humans. Now, how has hyperplasia been induced in animals that would be a good place to start? Unfortunately this required some strange, and in some cases pretty cruel and unusual.

Punishments, protocols, to, to create hyperplasias things that you just couldn’t do in humans. For example, in one study, scientists found that they could cause a 294% increase in muscle size due to hyperplasia when they attached progressively heavier weights to a bird’s wing for 28 days in a row, 28 consecutive days.

In another study, researchers found that they could cause hyperplasia in rats. Cutting them open and partially destroying some of their muscle tissue and then letting it heal. In another paper, scientists found that hyperplasia occurred in salmon as they developed during adolescence, mysteriously interesting.

Great for salmon and. These types of experiments, they make it difficult to draw any firm conclusions about what actually causes hyperplasia to, to find a pattern. And of course, it would make it even harder to try to extrapolate that information to humans what could cause that in our muscles. And while there are a handful of studies on muscle hyperplasia and humans, unfortunately, They contain a lot of methodological issues.

So for instance, multiple studies show that bodybuilders have significantly more total muscle cells than people who don’t exercise regularly. That’s an interesting observation that has led some people to suggest that all those years of heavy weight lifting, high volume weight lifting, has caused hyperplasia.

That’s why they have. Total muscle cells, and that is a fine hypothesis, but there are some problems with that line of thinking. One, we have no idea how many muscle cells everyone had to begin with before the studies looked at these jacked. People, It’s possible. And I would say it’s probably likely that the bodybuilders in these studies were just born with more muscle cells than the sedentary people, and that also may help explain why they got into body building.

Because they found that they were just uniquely suited to this, they could just respond really well to training and gain a lot of muscle and strength and gain it a lot faster than the average person, which you would expect of course to happen with somebody who comes with more muscle tissue from the womb.

Another issue is these studies did not directly measure or demonstrate muscle hyperplasia. Instead, they just found a correlation between bigger muscles and more muscle cells. Of course, then hyperplasia may or may not have been involved, or may not have caused that to occur. And finally, most other studies have found that bodybuilders and sedentary people have the same number.

Muscle cells and that would indicate that most bodybuilders have bigger muscles through hypertrophy, through growing their existing muscle cells, not through adding new ones. And then there is the always present elephant in the room when we are discussing body building. And that is steroids, Vitamin S, because not only.

Do steroids allow you to get a lot more hypertrophy out of the muscle cells that you have. Research shows that they may, certain drugs may also help you grow new muscle cells. For example, studies have shown that steroid users consistently have significantly more muscle cells than non-steroid users, and not just bigger muscle cells, but more muscle cells.

Now, again, these people may have come with. More muscle cells to begin with, but it is an observation that we should note, and that’s an observation that might also help explain why people who have used steroids in the past tend to keep some of their chemically enhanced gains years after they stop taking drugs.

And to put that another way, what you will often see among long term and heavier steroid users who got really big and really strong is when they come. The drugs, they don’t stay as big and strong as they were when they were on the drugs, but they stay bigger and stronger than they were before the drugs.

And that has held true in many people who were advanced. Trainees before they started taking drugs, meaning they had already gained most of the muscle and strength genetically available to them before they started taking drugs. So then they start taking drugs. Then they get super jacked. Eventually they come off of the drugs and their new cruising altitude to use an apt pun.

, their new normal is now bigger and stronger than they ever were before taking drugs in the first. Now another study on hyperplasia in humans that is often cited as evidence of its occurrence looked at people who are not bodybuilders. And in this study, scientists autopsied the left and right anterior to be Alice muscles.

So those are the muscles that lie close to your shin. Bones of seven previously healthy right-handed. With an average age of 23, and they use this method because everyone uses their body asymmetrically. So about 90% of us have a right side bias, which causes muscles on each side of the body to develop differently.

And for most people, this results in muscles of their non-dominant leg being larger and stronger than the muscles of their dominant. Leg, which I know is counterintuitive, but it’s true nonetheless. And also, the lower leg muscles are used in many daily activities. So any differences in how these muscles develop should be more pronounced in other lesser used muscles like the biceps.

And the results of these biopsies showed that there were 10% more muscle fibers on average in the left muscle. Than the right which researchers believed was best explained by hyperplasia. And that seems plausible until you realize though, that muscle biopsies can be wonky. For example, one study that used muscle biopsies to measure fiber type composition found that duplicate biopsies were up to 12%.

  1. From one another, and that was probably due to measurement errors and also muscle fibers. They don’t run from one end of a muscle to the other, which means that you can get very different results if the biopsies are taken at different points along the same muscle. But regardless. If we were to take this study I just referenced at face value, if we were to agree with the researchers best hypothesis, it would suggest that we are only likely to experience a very small amount of muscle growth after a lot.

Yeah. A couple of decades of continuous training. Again, if we looked at the data in the study, it would show about 10% growth because of hyperplasia over about 23 years of constant use. If hyperplasia does exist, it would appear to take a very long time to occur and it will not contribute greatly to the size and strength of our muscles.

Now, a notable exception, as I mentioned, may be steroids, and I’m not recommending steroids. In fact, I recommend against. Steroids. And if you want to hear my thoughts on that, I have produced a couple of podcast episodes on over the years. So if you just search for steroids in whatever app you’re using to listen, then you can find them.

And if you’d rather read, head over to legion, search for steroids, and you’ll find a couple of articles I’ve written over the years that explain why. I believe for most people, the risks that come with steroid use are just. Too high. They’re not outweighed by the benefits. There are exceptions, and I talk about this, professional athletes, actors, people who make a lot of money with their body, whether it’s through performance or looks.

But for most of us who are not a professional athlete or a Hollywood actor I don’t think it makes sense. So let’s shift gears now from the theoretical to the more practical. Let’s talk about hypertrophy. Hypertrophy is straightforward. We know how to trigger hypertrophy. It’s resistance training. It’s spending the majority of your time.

In that resistance training with relatively heavy weights, let’s say between 70 and 95% of one rep max, and it’s doing 10 to 20 hard sets per major muscle group per week, and a hard set is a set taken close to failure. Doesn’t have to be up to. Muscle failure, but in your primary exercises, your big compound exercises, you generally want to have one to two good reps left, let’s say around two.

In your first set, let’s say you’re doing four sets. In my training, I like to feel like I have. Two, maybe even three good reps still in the tank when I end that first set and then by the fourth set, that’s usually a one to two. Sometimes it’s a zero, but it’s usually a one to two good reps left. I am basically never going to absolute failure.

With a big compound lift and then with accessory exercises, which are safer and don’t involve as heavy of loads. Then I like to have one to two good reps left in my first set and zero to one good reps left by my final set. And often I’ll go to zero where if I tried to go for another, I will fail. Now, why does that training work?

Why does it produce hypertrophy? It creates enough tension in your muscle fibers to activate specialized proteins in muscle cells, and then that kicks off a cascade of genetic and hormonal signals that then stimulates the body’s muscle building machinery. It tells the body it’s time. To make our muscle cells bigger, and a key enzyme involved in this process is one, you’ve probably heard of the mammalian target of rapamycin or mTOR, and that boosts protein synthesis, the synthesis of muscle protein.

And there you go. You have hypertrophy. Now, what about hyperplasia and training? My position is while it may occur in humans, it’s not clear if we can cause it, if it is going to occur, if we can cause it, it is probably just gonna be a side effect of doing what I just described. It’s going to be a side effect of proper hypertrophy training, and it’s almost certainly not going to be something that we can boost with special diet or training techniques, but, Some people would disagree with me.

Some people have, and usually sell diet and training protocols that can cause hyperplasia. They claim or can greatly increase hyperplasia. And since the largest increase in muscle fiber, Number count occurred in animal studies that used extreme weighted stretching. Some fitness gurus claim that you can do the same thing just on a smaller scale and get very similar results on a smaller scale.

No, it’s not going to be 294%, but it could be 29%. Now what this normally comes down to is stretching in between sets and using high reps and lightweights in an attempt to mimic the protocols used in some of these animal studies. And while at least one study has shown that stretching alone can cause muscle growth in humans, but through hypertrophy, not hyperplasia and.

Others have found an association between weighted stretching and an increase in anabolic hormones in the body. There are no studies that have found stretching or weighted stretching can cause hyperplasia. And by my lights, the theory here just doesn’t make sense. Let’s say you take this advice to heart and you stretch every day, 20 minutes per day, and you do 20 high rep low weight sets per day for a muscle group, and you somehow don’t get injured.

That is still nowhere close. To the extreme protocols used in some of these studies, that is nowhere close to, for example, loading that muscle with a weight for 28 days straight. And so for now, until research comes out that shows that I am wrong and that we can meaningfully increase hyperplasia without doing anything.

Absurd or obscene stick to the time proven fundamentals of hypertrophy and strength training. I know they’re not very sexy, but they work in every person every single time, and chances are they are all you need to get the body you really want. I hope you liked this episode. I hope you found it helpful, and if you did subscribe to the show because it makes sure that you don’t miss new episodes.

And it also helps me because it increases the rankings of the show a little bit, which of course then makes it a little bit more easily found by other people who may like it just as much as you. And if you didn’t like something about this episode or about the show in general, or if you. Ideas or suggestions or just feedback to share.

Shoot me an email, mike muscle for, muscle f or and let me know what I could do better or just what your thoughts are about maybe what you’d like to see me do in the future. I read everything myself. I’m always looking for new ideas and constructive feedback. So thanks again for listening to this episode, and I hope to hear from you.

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