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The number one most requested product of my sports nutrition company, Legion, is something I refuse to sell.

That product is BCAAs (branched-chain amino acids), and it’s one of the most popular supplements in the body composition space.

Many people claim that BCAA supplements are essential for muscle growth, improve immunity, and even help with fat loss. In this podcast, I’ll explain why BCAAs are actually worthless and how the science used to sell these supplements is often misrepresented or even fake.

So, click play and stay tuned as we explore the world of BCAAs, discuss their perceived benefits, and uncover the reasons why you might want to skip them altogether.


0:00 – Please leave a review of the show wherever you listen to podcasts and make sure to subscribe!

3:32 – What are BCAAs?

7:32 – What studies show that BCAAs show significant muscle growth?

18:07 – Try Whey+ risk-free today! Go to and use coupon code MUSCLE to save 20% or get double reward points!

20:42 – Do BCAAs reduce fatigue?

24:18 – BCAA’s and recovery

25:40 – Can training in a fasted state with BCAAs increase muscle growth?

30:08 – What are some good alternatives to BCAAs?

Mentioned on the Show:

Try Whey+ risk-free today! Go to and use coupon code MUSCLE to save 20% or get double reward points!

What did you think of this episode? Have anything else to share? Let me know in the comments below!


Hey there, I’m Mike Matthews. This is Muscle for Life. Thank you for joining me today for a new episode on BCAA’s Branched Chain Amino Acids, which are one of the most popular supplements in the body composition space, and one of the few. Popular supplements that I don’t offer, that my sports nutrition company Legion does not sell and probably will never sell despite the magnitude of the economic opportunity.

This is the number one most requested product people ask us every single day. Now, just because of the popularity of legion’s popularity, we get a lot of emails and a lot of. Website chats. So every single day, multiple people ask me or people on my team who work with me, why we don’t sell BCAAs, if we are going to sell BCAAs, what our position on BCAAs is, or what my position on BCAAs is.

And so I thought it would be worth. Recording an episode. I have of course commented on this in previous episodes, but I don’t think I’ve done an in-depth or if I have done an in-depth episode or a more in-depth episode on BCAs. It was some time ago, and so I thought it would be a good idea to give my take on BCAs as of March 13th.

  1. And so here we are now, if you have looked into sports supplementation at all, you’ve probably heard about BCAAs. You’ve probably also heard about EASs Essential Amino Acids. And although I’m going to be focusing on BCAAs in this episode because it’s the more popular supplement that I get asked.

The most about everything that I’m going to share in this episode applies equally to eaas. I don’t take eaas and I don’t sell eaas, and I don’t recommend eaas for the same reasons that I don’t take seller. Recommend BCAAs. And if you are new to all of this, especially the supplement racket, you might be a little bit surprised because if you look around on social media, you’ll find a lot of people who are in great shape sometimes who are well educated, well-spoken, talking about how great amino acid supplements and, and BCAs in particular are, many people say that BCAs are, are just one of the.

Best supplements that you can take for boosting muscle growth. Sometimes they will say, oh, well, when you’re lean bulking in particular, sometimes they will say when you’re cutting and BCAs are good for body recomposition, when you are cutting for gaining muscle and losing fat at the same time, or minimally for preserving the lean mass.

That you have when you are cutting or maintaining energy levels. When you’re cutting. Many people also claim that BCAs can improve your immunity, your body’s ability to recover from training and even help you lose fat faster. And often these people will share citations. They will share PubMed IDs that purportedly.

Support their claims and it all sounds great until somebody like me comes along and explains why BCAs are actually worthless. And a lot of the purported science that is used to sell these supplements is either misrepresented or possibly even fake manipulated to appear a certain way. That sheds a positive light on BCAAs when the reality was otherwise.

Okay, so let’s start with a brief explanation of what BCAs are. It stands for, the acronym stands for Branched Chain amino Acid, and that refers to a group of three essential amino acids, which are amino acids that we must get from food. Our body can’t create them from other amino acids and other compounds.

And those three are leucine, isoleucine, and valine. And the reason they are called. Branched chain amino acids is they’re chemically chained together, chemically linked together. Now, what is the significance of essential amino acids, especially in the context of body composition? Well, protein. Is a large molecule and it’s made up of chains of smaller compounds known as amino acids.

And these amino acids are the building blocks, so to speak, of the protein molecules as well as many tissues in the body, including muscle, hair, nails, and skin. Now, I mentioned a minute or two ago that there are essential amino acids. That your body must obtain from food and there are nine of them. And then there are 11 amino acids that it doesn’t have to obtain from food, it can create from other substances.

And those nine, those essential amino acids. Are particularly important to those of us who are trying to gain muscle and retain muscle and are one of the primary reasons we need to eat a high protein diet to maximally improve our body composition. Our body needs a lot of these essential amino acids to recover from our training and to get bigger and stronger.

And so you understand now why the B C A A supplement came about in the first place and why it has remained so popular for all of these years. It provides essential nutrients for people who are trying to improve their body composition. There’s no question about that. And further evidence supporting the theory, I guess you could say.

Underpinning the existence of BCAs and. The use of BCAs and the sales pitch of BCAs are studies on each of the amino acids individually, and leucine in particular is the star because studies show that leucine directly stimulates protein synthesis, the creation of new protein molecules in the body, and.

That means that leucine plays a vital role in muscle building, particularly in Kickstarting, the muscle building process kickstarting the body’s muscle building machinery, I guess you could say. Now, ISO leucine has different effects in the body. Research shows that it improves glucose metabolism and it increases glucose uptake into the muscles in particular, which could help you train longer, could help you train harder, maybe increase muscle endurance to some degree.

And studies show that valine doesn’t appear to do much compared to leucine and isoleucine. However, there is evidence to suggest that it can activate an enzyme that is responsible for cell growth, known as the mammalian target of rapamycin or mTOR, as it is often referred to. Now from here, if I were trying to sell you BCAs, I could refer to a couple of studies that show that it does appear to augment muscle building.

That if you take, however you are eating right now, even if you are eating a high protein diet and you. Add A, B, C, a, a supplement on top of it, you are going to gain muscle faster and depending on which study I want to cherry pick, I could quote unquote credibly claim that you are probably going to gain a lot more muscle.

You are going to gain muscle a lot faster with the BCAs in your regimen. But unfortunately our branched chain emperor has no clothes because when you scrutinize the research, when you really look at the details, you quickly lose your enthusiasm. So let’s first talk about studies that purportedly show that branched chain amino acids help you gain muscle faster.

But. The problem with a number of these studies that have been bandied about over the last decade or so that I’ve been in the fitness racket is protein intake, and specifically one of two things. In some cases, protein intake is way too low. Like in one case, there was a study that was conducted with college athletes where they were eating about 0.5 to 0.6 grams of protein per pound of body weight per day, muscular.

Men training very hard, eating 0.5 to 0.6 grams of protein per pound of body weight per day. And for the sake of reference, they should be eating or should have been eating close to about one gram of protein per pound of body weight per day, given their body composition and given the frequency and the intensity of their training.

And so under those conditions, yes, supplementing with BCAs actually would be helpful. It would at least help you retain muscle because if you. You are a lean athlete and you are training many, many hours per week, and you are only eating 0.5 to 0.6 grams of protein per pound of body weight per day. You may end up losing muscle, especially if you are restricting your calories.

Maybe you are a wrestler and you are dieting to make weight. You are. Going to lose muscle, I can guarantee it. If you are in a significant calorie deficit, you are training many hours per week, and you are only eating 0.52, 0.6 grams of protein per pound of body weight per day. In that case, if you couldn’t simply eat more protein, then a BCA supplement.

Would be helpful. It would. But what if you can just eat more protein? Well, I’m gonna talk about that in a minute, but let’s get to another problem with a number of studies that are used to sell people BCAs, and that is different amounts of protein intake. In different groups of people. And so in some cases you have studies where you had a group of people eating around 0.52, 0.6 grams of protein per pound of body weight per day, and doing a fair amount of exercise strength training in, in a couple of cases I’m thinking of, and restricting calories, which of course can lead to muscle loss, especially if you are training fairly intensely and you are not eating enough protein.

So you have one group of people who appear to be. On a protocol expressly designed to either cause muscle loss or if calories are not restricted to hamper muscle growth. And then you have another group of people who are doing the same workouts, but who are eating a lot more protein upward of 0.82, one gram of protein per pound of body weight per day, and taking a, B, c, A A supplement.

Those people are then monitored for a couple of months. They follow their regimens and there are regular data collections, measurements of various things. And you also would have a controlled group of course, taking a, a placebo supplement. But then at the end, the scientists crunch their numbers and. What do you know?

The B C A A group gained a lot more muscle than the non B C A A group, but of course the question is, well, is that because they took BCAAs or is it because they ate a lot more protein? And the problem is those studies were not designed to answer that question, which is the real question you as a consumer have because you probably eat enough protein, you are probably not eating 0.5 grams of protein per pound of body weight per day.

And so you want to know are BCA is going to help. U not an under protein nourished U. Now, there are other studies that appear to be better designed and that do support the efficacy of BCAs and one in particular that is regularly cited as proof. Definitive proof. BCAs are great. They help you improve your body composition.

And this was conducted by scientists at Wheater Research Group and the researchers had participants follow a four day strength training program for eight weeks and supplement with either BCAs Whey protein or a Carbohydrate sports drink. And the results showed that the participants who supplemented with the BCAs gained significantly more muscle and strength and they lost at least.

Twice as much fat. So they were in a calorie deficit, two body recomp, and they lost more fat than the participants who used the other supplements. However, there are a few problems with this study. One is that it was never published in a journal, and so it never underwent peer review. Not that peer review is.

Perfect and fail safe and that bad research cannot pass peer review. Yes, it can, uh, loads and loads of bad research passes peer review every day, but peer review still is a useful mechanism for helping maintain certain standards of. Quality of research and quality of the representation of research and ensuring that the researchers’ words are backed up by the data.

Another problem with this BCA study from Wieder, from the Sweeter Research Group is the supplement wasn’t just BCAs, it also contained glutamine and citraline malate, which means it’s impossible for us to know how much the BCAs per se contributed to the results. And you could argue that there is no reason.

To believe that glutamine would contribute to those results, and I would agree. However, Citraline malate can contribute to muscle growth, in particular muscle performance in particular, we know that from other research, and so that is a confounding variable in this study that should not have been there.

It should have just been a pure B c, a supplement. Yet. Another problem with this study is diet was not controlled. And this is coming back to the point I was making a few minutes ago. It’s very important with a, B, C, A study and with any body composition study to control the diet, particularly the calories and the protein, because in this case, we don’t know whether the B C A A group made better progress because their diet was just better than the.

Other groups, they were maybe more consistent with their calories, more consistent with their protein, and that alone would explain the additional muscle growth and the additional fat loss. Now, there’s another study I want to comment on that is often used to prop up BCAs and it was published in the Journal of International Society of Sports Nutrition, and in it a group of participants supplemented with B C A A powder while diving.

And they lost more fat, and they maintained more muscle and gained more strength than a group of participants who were supplementing with a carbohydrate powder. And in this case, both groups were following identical training and diet regimens. Okay, better designed study positive results for BCAs.

However, a team of shrewd scientists later discovered and published their concerns about some of the questionable statistical analysis methods that the researchers in the first study, the study that apparently showed that BCAs can help you lose more fat and maintain more muscle and gain more strength.

And the second team of researchers showed that the. First team made several errors in handling their data and reporting their data that could explain the quote unquote results of their study. And that, of course, makes those results very hard to swallow, especially when you consider that. Both of the studies I just shared with you were funded by supplement companies who sell BCAs and who sell a lot of BCAs.

BCAs are one of their primary. Products. And that is not proof of scientific misconduct of course, but it does mean that we should be skeptical and especially when the industry funded research is at odds with the independent third party research. And so while I could walk you through a couple other studies and point out the flies in the soup and a couple of studies that were.

Independent third party funded that showed no such effects as some of this industry funded research, but take it from someone whose economic interests would be served by not recording this podcast and selling BCAs. And there’s a lot of money in BCAs. It would add millions of dollars a year to. Legion’s revenue given legion’s size and reach.

And that would also mean a fair amount of money that would come to me directly because one of the reasons BCAs are so popular in sports nutrition and sports supplementation is they’re very cheap. They are inexpensive, and people are willing to pay a premium for them because of all of the marketing that has hyped them up and convinced people that they are a, a premium muscle building supplement.

And so I wish there were otherwise, I wish the weight of the evidence supported BCAs. For people who also eat enough protein, I would use them myself. I would sell them happily. I would pitch them honestly, and everyone would be happy. All of the people who message me and message, uh, my team over at Legion every single day asking us about BCAs, they would be thrilled.

But alas, here I am. Not selling BCAAs declining millions of dollars a year in revenue for my company and telling you to not buy BCAAs. And I would go further and I would suggest that you don’t buy, not just BCAs from a company, from a sports supplement company. Don’t buy anything that company sells because the fact that they sell BCAs is a huge red flag.

That means that they either don’t know what they’re doing or they don’t care, meaning they haven’t looked into the matter. With any amount of scientific rigor they have simply said, Hey, there’s a market for this supplement. People want it. We are in the business of giving people what they want. So we are doing them a service by offering them BCAs and the science.

Well, I mean this study here, this weeder study that looks pretty good and oh, here’s this other study that’s even better. That’s it. What else do we need? Sold? One of the easiest ways to increase muscle and strength gain is to eat enough protein and to eat enough high quality protein. Now, you can do that with food, of course, you can get all of the protein you need from food, but many people supplement with whey protein because it is convenient and it’s tasty, and that makes it easier to just eat enough protein, and it’s also rich in essential amino acids, which are crucial for muscle building.

And it’s digested well, it’s absorbed well. That’s why I created Whey Plus, which is a 100% natural grass-fed whey isolate protein powder made with milk from small sustainable dairy farms in Ireland. Now, why Wei isolate? Well, that is the highest quality whey protein you can buy, and that’s why every serving of Whey Plus contains 22 grams of protein with little or no carbs in fat.

Way Plus is also lactose free. So that means no indigestion, no stomach aches, no gassiness, and it’s also 100% naturally sweetened and flavored. And it contains no artificial food dyes or other chemical junk and y Irish dairies. Well, research shows that they produce some of the healthiest, cleanest milk in the world, and we work with farms that are certified by Ireland’s sustainable dairy assurance.

Scheme, S D S A S, which ensures that the farmers adhere to best practices in animal welfare, sustainability, quality, traceability, and soil and grass management and all that is why I have sold over 500,000 bottles of way plus and why it has over 6,004 and five star reviews on Amazon and on my website.

So if you want a mouthwatering high protein, low calorie whey protein powder that helps you reach your fitness goals faster, you want to try Whey Plus today, go to buy Use the coupon code muscle at checkout and you’ll save 20% on your first order. And if it is not your first order, you will get double reward points and that is 6% cash back.

And if you don’t, absolutely love way plus just. Let us know and we will give you a full refund on the spot. No form, no return is even necessary. You really can’t lose. So go to buy now. Use the coupon code muscle at checkout to save 20% or get double reward points and then try way plus risk free and see what you think.

All right, so now that the claim that BCAs can improve body composition is in tatters, let’s switch gears and talk about fatigue because this is a rather new selling point that many supplement marketers are relying on because many consumers are now skeptical of any claims about the purported muscle building effects of BCAs.

And as you can expect, The research for BCAs reducing fatigue, and this is often promoted to athletes, endurance athletes. In particular, the evidence is, is flimsy. It’s pretty thin. For example, one study that was conducted by scientists at the National Taiwan University of Sport showed that handball players who supplemented with BCAs and arginine were less fatigued after playing a multi-day competition than players who supplemented with a placebo.

Okay, interesting. But the BCAs were mixed with. Arginine, that’s a problem. We can’t be sure that the BCAs were responsible for any of the benefits that were seen. It is equally likely that it was the arginine or it was the mix of the two together, or it was something having to do with their diets.

Further evidence that you can’t hang your hat on. The handball study comes from a study that was similar, but it was conducted with wrestlers and it was in a single day competition, and it failed to replicate the findings of the first study. And replication is a very important component of the scientific method.

If you can’t. Reliably replicate findings. Something is wrong. Now, you could say that BCAs may only benefit athletes when they have to perform at a high level for more than one day, and some people have said that to try to discredit the use of the wrestler study to discredit the handball study. But that is simply speculation.

There isn’t research to support that theory. It’s just a theory. And one final interesting point I want to share with you is research that shows that BCAs can increase the amount of time that it takes to reach exhaustion during endurance exercise. So it is reducing fatigue levels because you can only push yourself so hard until you gotta back off, but, That was seen only when people did not have enough glycogen, which is a form of carbohydrate stored in your muscles and stored in your liver.

And so what it was seen is when people did not have enough glycogen stored in their muscles, supplementing with BCAs increased the amount of time that it took for them to reach exhaustion during endurance exercise, but not when they had enough glycogen. In their muscles. And so then it is fair to say that well-designed research does seem to show that when you are glycogen depleted, BCAs may make exercise feel easier.

But there’s a problem because similar to trying to use BCAs to get essential amino acids instead of just eating protein, that’s the best way to get enough essential amino acids, just eat enough protein similar. If you are glycogen depleted and you need to continue performing at a high level and you care enough about your time to exhaustion, to supplement with BCAs, you should just eat carbs instead, because research shows that carbs are much more effective at achieving that and cheaper than BCAs.

So if you want to perform better in your workouts, in your sports matches, in your training, whatever, a couple of bananas. Is going to help you more than a blender bottle of BCAs. Next up, we have BCAs and Recovery. This is another common claim used to sell them, is that they can decrease muscle damage, they can improve post-workout recovery, and there are studies that show that that can be the case, but.

Major methodological problem. These studies only compare BCAs to either nothing, water or carbs. So what’s missing here? What is the post-workout meal and in some cases even pre-workout meal, what’s the, what’s the macronutrient, the most important macronutrient that you would want to test BCAs against that?

Basically everyone. Into fitness consumes before or after workouts. Oh, that’s right. It’s protein. And isn’t that odd that these studies were not designed like that? It’s almost like they were designed explicitly to obtain the desired result. And maybe that’s because Noel research research that shows no effect.

Isn’t generally as valuable to a researcher’s resume than research that does show an effect, and if it doesn’t show an effect, it may not even be published at all Anyway, in addition to all of that, there are also a couple of studies that have shown that BCAs did not enhance post-workout recovery and people who are also eating enough protein, so there’s that as well.

Now, lastly, I wanna talk about fasted training. Because this is one of the final segments, I guess, of the BCA market that is worth addressing because there are many people who like to train in a fasted state, which is a state rear body, has finished processing and absorbing the nutrients in the food that you last ate, and now your insulin levels are at a low minimum baseline.

Level, and many people believe that training in a fasted state results in more fat loss, which it does in the short term over the course of a workout. But research shows that it does not over the course of a 24 hour period, because while your body burns more fat in your fasted workouts, it just. Burns less fat throughout the rest of the day compared to a fed workout where your body is burning more carbohydrate and less fat in a workout, but then burning more fat throughout the rest of the day.

So basically, there’s no way to get around energy balance, and if you want to get leaner, just manage your calories properly, maintain that calorie deficit, eat enough protein, and let your body take care of the rest. However. Quick exception to that rule is if you add Yohimbe, which is a stimulant that enhances fat loss and enhances quote unquote stubborn fat loss in particular, but requires you to be in a fasted state.

Research shows that if. Insulin levels are elevated. It completely negates yohi being’s fat burning effects. It will still work as a stimulant, but not as a fat burner, so to speak. And if you wanna learn more about that, just head over to legion, search for Stubborn Fat, and read the article I wrote on Stubborn Fat, what that really means and why certain fat stores are harder to lose than others, and how Yohi being can help.

But in the absence of Yohi being, and maybe you could say rine, I guess they’re. Isn’t a good reason to train in a fasted state unless you like it. Some people don’t like having anything in their stomach. Even a protein shake or an apple, like that’s what, when I was training early in the morning, I would just have a protein shake and a banana or two.

That would be my pre-workout meal, cuz I do not like training with a full stomach, especially if I’m squatting or deadlifting. I’ve almost thrown up because of that. But I also. Don’t particularly like training on an empty stomach if I’m a little bit hungry. And so I’ve done it many times when cutting, when lean, wanting to get really lean when taking Yohimbe along with some caffeine and sevrine.

But generally I prefer to not feel full, but just not be hungry. And so I like a, a simple pre-workout. Meal. But anyway, when you are training in a fasted state, there is a disadvantage you should know about, and that is increased rates of muscle breakdown. Research shows that muscle breakdown rates tend to be higher, especially after a fasted workout.

And also fast training can impair performance as well, which means. At least slightly worse results, especially if you are consistently performing more poorly than you would otherwise. And that’s where BCAs purportedly can help. Now, according to most supplement manufacturers, BCA supplements contain zero calories.

And so then people think, okay, great. This is not going to break my fast. This is not going to spike my insulin levels and therefore, I can use this to mitigate this increased rate of muscle breakdown. However, research shows that BCAs do contain calories and they do raise insulin levels. Now, you could say, and you would be right to say that they don’t raise insulin levels nearly as much as a scoop of protein or a banana or two bananas, and that the effect.

It appears to be about 15, 20 max, 25 minutes, and then your insulin levels are back down to that low baseline level. You are back in a fasted state. And yes, those things are true, but many B C A A hucksters won’t even tell you those things they say. No calories, no insulin response. Not true and not true.

And the 15 to 20 minutes of elevated insulin levels, depending on when you take your BCAs, that might be a third or a half of your quote unquote fasted workout. That’s not quite fasted. Okay, well that’s everything on my list. Those are all the reasons I currently have for not taking BCAs, not recommending BCAs, and not selling BCAs.

And before I sign off, I want to quickly comment on a good alternative to BCAs for fasted training. It is called. Beta hydroxy, beta methyl butyrate or just H M B. And that is a substance that is formed when your body metabolizes leucine, which is one of the three branched chain amino acids. And while most research shows that H hm B is not a muscle builder, that it was once believed, To be.

That’s how it was once sold. Some people are even saying it’s the next creatine. No, it’s not. However, studies do show that it seems to be very effective at preventing muscle breakdown, and it also has no effect whatsoever on insulin levels, which means it does not break your fast, does not take you out of that fasted state.

And therefore, H M B is perfect for use with fasted training. If you have a good reason to do faster training, like for example, faster fat loss. So if you’re gonna take the caffeine and the yohimbe, maybe some rine, it does make sense, I think, to include, hm. B, if you also want to minimize muscle loss, if you want to maximize your body composition benefits from your fasted training.

And if you are interested in giving that a Go Yohimbe and hmb in particular, check out my Product Forge because it has Yohimbe and it has Hmb. It also has Cline, which you can learn about over at buy B uy Well, 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 have. Uh, ideas or suggestions or just feedback to share.

Shoot me an email, mike muscle for, muscle f o r and let me know what I could do better or just, uh, 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 soon.

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