If You Want To Build Muscle FAST You Need To Start Doing THIS! | Brad Schoenfeld

0:00The majority of literature shows that if you just do a half repetition in the lengthen portion, it's as effective as doing the full range of motion. What? We can also build muscle by doing high reps and low weights. It disproves everything that we thought we knew over the last 20 years. Certainly some research supporting it, that type 1 fibers might be more predisposed to growth with lighter loads and type 2 fibers might be more predisposed to growth with heavier loads. If that is the case, combining some higher rep training and some lower heavier and lighter load training

0:33might optimize hypertrophy to a greater degree. Do you think that we've got a problem there with maintenance and building muscle because of GLP-1s now? GLP-1s, they tend to induce greater or more rapid weight loss. More rapid weight loss is generally associated with more rapid muscle loss. What is the single most dangerous lie being told right now about how to build muscle? One of the things that I think is really counterproductive is... I'm Louise Nicola and this is The Neuro Experience.

1:08Brad, this is a very exciting time for me. You and I have known each other for quite some time. We met back in 2020 and here we are. And since then, I believe that you are one of the most highest published people in the area of muscle growth. I think you've got now around 400, close to 400 papers, close to 400. When you first started out in the 90s, you were a personal trainer and then you went into academia. And just as the natural progression in life, things change and that's what science does.

1:42What do you think was a belief that you held back then in the 90s as it related to hypertrophy and muscle growth that is no longer true? There's been quite a few. I think the one that stands out probably the most is that you have to train all-out failure to optimize muscle development. So I came from the old school. Either you go all out or you go home. If the vein in the side of my head wasn't bulging at the end of every set, I wasn't training hard enough. And the research that we have on the topic now really shows you can be a couple reps or three short of failure

2:19and still get roughly the same amount of muscle growth, which is, first of all, it's a revelation given my previous thoughts, like the old bodybuilding school mentality. Not only was I training to failure, but I was doing drop sets and four straps.

2:36But it also, I think, has a lot of importance for adherence because a lot of people don't want to lift weights or are averse to it because there's discomfort involved in the closer you are to failure. If you're, you know, if you go to muscle failure, there'll be more discomfort. So the fact that you can stay a couple reps short of failure, which, by the way, is still training really hard. People think, well, you're a few reps. If you're not training to failure, it's no, you're not really training hard. If you're a couple reps short of failure, you're still training really hard. But it's not, certainly not as discomforting as it would be if you go to a lot of failure.

3:11And I think that can help with adherence in the general public. And I think the last stats I saw was that 80% of the population does not lift weights on a regular basis. Or when I say lift weights, perform resistive exercise, which encompasses lifting weights and can be other bodyweight exercise. But the statistics are pretty grim given the importance of resistance training. Yeah, I think you can probably agree with me. We've seen this massive influx of people really understanding the term longevity.

3:45Muscle as a longevity organ, the importance of muscle. I think it really took place, even though you as a scientist have always known this, but I think the general public has now understood in the last three to four years, hey, muscle is important. So I think we've seen this uprise of people doing resistance training. Yeah, it's getting better. That's not saying much. Like I said, there's still a huge number of, huge percentage of the population that doesn't. So a lot of times people can know, yeah, it's beneficial, but I don't have time or I don't want to go through the effort involved and whatever the excuse is.

4:23So it's one thing to know that something or to have heard research on the topic. It's another thing actually to put it into action. And I think that's where these types of revelations can help to promote adherence, participation. Yeah, exactly. I think I really want to start and open up the field of longevity and you're at your third edition for your book. Correct. Have you included longevity in this third edition?

4:53Well, not really because it's focused on just the optimization of muscle development, not only optimization, but just the development of muscle size, muscle mass and optimization as well. So it kind of, maybe in a future edition, that can be something to touch on, but it's such a wide ranging field. I mean, I do touch on sarcopenia and the effects of aging, certainly, but getting into the health related benefits is somewhat outside the scope of the book. I want to ask a left field question.

5:24With the amount of resources that we have right now, the amount of information on hypertrophy, what do you think makes this book different? Well, it really is not only the first, but still the only book that has really delved into the scientific aspect of understanding the mechanistic aspect and then putting the mechanisms into perspective with the application. There's a lot of books that are just more guidelines as to you with a lot of opinions based.

5:55This really is a scientific book. It's a textbook and there really is no other, certainly that I'm aware of, textbook that just deals with muscle growth. So I want to go into some of the biggest subjects within that book. And I actually want to start with a study that I read with Stu Phillips, and this is the one that you were talking about, where I documented this on Instagram, like I think it was in December. And it was the first time that I've seen an academic paper really put forward the fact that what you just said, that we can also build muscle by doing high reps and low weights.

6:31Which is amazing because it disproves everything that we've thought we knew over the last 20 years. Can you walk me through the mechanisms by which that happens? Yeah, sure. So, first of all, that's certainly another area where I've almost done a 180 on in terms of my opinion, because it was always taught that you did really light weights. You're not going to do a, not going to build a appreciable muscle and funny, somewhat funny story. It's funny looking back at it, but Stu actually, Stu's a good friend of mine and a terrific researcher.

7:03He published a paper back in 2012 on untrained subjects, just doing leg extensions. And he looked at 80% 1RM versus 30% and showed that 30% and 80% had virtually identical growth. And I'll never, he posted this on Facebook. I went on Facebook and I said, come on, Stu, these are untrained subjects just doing leg extensions. I said, they can do spin cycling and they'll get jacked. I said, I'm going to carry the same study out or a similar study in well-trained subjects, total body workouts. You're going to see it's not going to be enough stimulus to promote substantial muscle.

7:38Well, long story short, a year later, I finished that study and no difference. It's basically the exact same results. And there's been literally dozens of studies over time since then that have showed the same thing. If you're asking mechanistically, it's somewhat difficult to tie in mechanisms, but at least the speculation is, is that the mechanical tension is long. So it's predicated by the way, the lightweights are training very close to failure, to failure, or close to failure. As long as you have substantial effort, the last repetitions are going to promote substantial mechanical tension, which is the primary driver of hypertrophy.

8:14Um, and thus you're going to induce similar, somewhat similar muscle growth. I'll say this, the one caveat that I'd give is that there may be differences. And I want to firm this in the perspective that it's may, because we don't have good evidence on it yet, but there's some, certainly some research supporting it. That type one fibers might, uh, might be more predisposed to growth with lighter loads and type two fibers might be more predisposed to growth with heavier loads.

8:44And by the way, type two, for those who don't know, type one fibers are endurance related fibers and type two fibers are quote unquote strength related fibers. Conceivably, if that is the case, combining some higher rep training and some lower, heavier and lighter load training might optimize hypertrophy to a greater degree, whole muscle hypertrophy. But on a whole muscle basis, if you just look at one versus the other, virtually identical growth. I want to talk about the difference between type one and type two, as you just elucidated, but from my understanding, type two is the one most closely linked to longevity and the one that atrophies the fastest.

9:23Is that correct? So we, we lose it as we get older. Correct. Yeah. And sarcopenia is the age related loss of muscle. So, and, uh, over time, the type two fibers are more predisposed to atrophy than type one, uh, various, at least speculative reasons. And not only that, there's evidence that if in severe cases of sarcopenia, there's actually programmed death of where actually you lose the type two fibers. And it's very important from a functional capacity because that isn't the type two fibers are involved in power and people experience falls as they get older.

9:58Or these type two fibers are what helps to reverse the fall. You're not able to avoid a fall if you don't have a lot of power producing fibers. One of the best ways to improve brain energy metabolism is to make sure that you have adequate ketones circulating in your body. This is why I ingest ketone IQ. I'm obsessed with ketones. They're one of the brain's most efficient energy sources, especially as we age and glucose handling changes. I use it for deep work or for long days when I want to focus without caffeine or crashes, but I also use it just in my day-to-day to make sure that I am neurologically adequately fueled.

10:42If you haven't tried ketones, you must. These ones taste great and you can get 30% off your subscription at ketone.com slash neuroplus. Get a free gift with your second shipment. So it's really important to be able to maintain those. Type two fibers, yeah. And can we regrow them? Generally, no. You can make the fibers that you have bigger. So it's not like you lose all the type two fibers, but there's some of the data I've seen, there's a loss of, it can be up to 25% of them, but you can make the type two fibers that you have larger.

11:17Again, I think the, at least from the literature I've seen, the death has to do with nerves being not innervated properly. If the fibers are not properly innervated by the nerves, you're going to lose the capacity to develop the fiber.

11:33But you can make the fibers that you have stronger and bigger and stronger, and thus you can help to avoid falls and other functional aspects. When we look at the literature on brain health, right, we've seen, and I've published on this, that even just two days a week of resistance training can have meaningful effects on mild cognitive impairment and Alzheimer's disease risk. We're seeing a reduction of upwards of 30% to 50%, right, which is really big.

12:04And that's just two days a week. But where I, what I'm trying to understand is, you know, when you go back to the, you know, higher reps, lighter weights, it doesn't involve as much neural real estate, you know, from a neuromuscular perspective, right? So when we're lifting lighter weights, we're not really activating as much neural real estate in our brain. Is that correct? You know, certainly the neural, neurology is not my area of expertise. So I'm certainly aware of a lot of literature on, first of all, on mood depression.

12:36There's a lot of evidence. Muscle itself secretes myokines, which are substances produced within the muscle. And some of them are sent throughout the bloodstream. One of them is BDNF, which is involved in brain health. So developing your muscles themselves helps to produce the myokines. If you're asking during the actual activity of lifting, I'm not aware. Like motor unit recruitment. Well, the motor unit recruitment is going to be somewhat, so there might not be as high type 2 fiber unit recruitment.

13:09That's where I talked about preferential type 1 versus type 2 hypertrophy. But what I'd say is the evidence we have, even if it's not complete type 2 recruitment in high rep and lighter load training, you're getting a substantial portion of the motor unit pool. And again, this is predicated on training the failure. I think that's one of the limitations with some of the research. They'll look at lightweight training where they're stopping 10 reps short of failure. And you're not stimulating the muscles, first of all, and likely not stimulating brain activity, I would assume.

13:43But again, that's really somewhat outside of my area of expertise. So if somebody listening to this is thinking, okay, so I can go into the gym and I can really just perform lightweights. But there is a caveat, as you said, we do have to be getting to a failure and we have to be fatiguing. Close to failure. Close to failure. And are we talking like we can go upwards of, because I wouldn't see a Mike Isretel in the gym doing lightweights, for example, to failure. Maybe.

14:13I don't know what his training schedule looks like. But I would imagine that men are choosing still to go back to the old, you know, phase, which is, you know, three by 10 or four by 10 reps. Yeah. So a couple of things there. Number one, we have evidence up to 30 to 40 reps can produce roughly similar whole muscle hypertrophy as 10 reps. Now, the question then becomes, what is the practicality of it? And what I'll say is, high rep training is not fun if you're going close to failure.

14:45So a study we carried out that I mentioned was on resistance-trained individuals that had an average of three to four years training experience. Half of them puked the first week of training. I mean, there's a lot of acidosis that is produced during the training. Now, it does dissipate, so the early phases, if you keep doing it, you're going to get, just like almost anything, the body acclimates to it. But it's still not, the longer you're under tension, the more unpleasant it gets to be. And that's why, you know, when you're training with lesser, with heavier loads and thus less reps, you get the set over with quicker and people can deal with it better.

15:21So I'm not saying that you should be using lighter weights, although I am saying that if you're a bodybuilder, I do recommend having some sets that are in the 20 to perhaps 30, upwards of 20 reps, just because you may get type 1 benefits. And if you can optimize type 1 and type 2 hypertrophy, the combination can give you conceivably greater whole muscle hypertrophy. You don't have any evidence to the contrary that it hurts. There's some evidence that it helps. So, you know, I would say it's a worthwhile endeavor if your goal is absolute maximal muscle growth.

15:57On the other hand, though, I want to point out that a lot of older individuals, it's quite common, they have osteo issues in the joints. So let's say you have any type of joint-related issue and you're lifting with heavier loads, it's going to put a strain on the joints. And a lot of older individuals have difficulty, feel pain, discomfort when they're training with these heavier loads. It's certainly an option to train with lighter loads and still get roughly similar benefits.

16:30I'll also add, strength is not as high. You get greater strength with heavier loads. So there is, even though muscle growth is roughly the same or similar on a whole muscle level, strength does follow a dose response where the heavier loads do produce greater strength. That said, you still get quite good strength-related results with lighter loads. And from a functional standpoint, maximal strength probably is less important than muscle endurance. Most of your everyday tasks are more muscle endurance-oriented than maximal strength-oriented.

17:05I'm seeing a lot of, right now, a big proportion of women, especially, opting in for ballistic power movements because we're now seeing how important it is, especially for longevity, sarcopenia. What's your, do you want to just outline for us, like the difference between strength and power? Yeah. So, uh, strength is the ability to produce force. Power, it's a time component into it. So it's the ability to produce force over time.

17:37So the more quickly, the more rapidly you can produce force, the greater the power. That's the simple, kind of the simple explanation. From a training standpoint, that would mean if you want to train for power, you do need some powers built on a foundation of strength. So conceivably, you do want to have strength-type training, heavier loads. But you also, there's some quite compelling evidence that also doing some higher velocity training. I was involved in a meta-analysis of older individuals. And really interesting findings that adding power movements, meaning that on the concentric action, you lift it quickly and then you lower it under control.

18:14So a high-velocity concentric action and then a controlled eccentric action, uh, produce substantially greater functional improvements in older individuals than just training in the traditional slower style. Is that still heavy though, like at around 80% of 1RM? Yeah, I generally don't even like to talk about percent 1RM because at 80% 1RM, some people will be able to get 8 reps. Some people will be able to get 12 reps. Some people would be able to get 15 reps. There's a very wide range inter-individual.

18:46It also depends on the type of exercise, upper versus lower body, multi-joint, single joint. So I like to give more of a rep range, but that's in the traditional 8 to 10 rep range. So this meta-analysis you did, can you walk me through it a bit more? Yeah, so we looked at all studies and it's been a while since we published it, but I believe it was 65 and older. They had to be average age, 65 and older. And, uh, we looked at all, uh, studies that had a functional component, like a get up and go test, a sit to stand test.

19:18These are all basically power type of functional, uh, type tests that's done assessments in older individuals to see their functional capacity. And we looked at, uh, each group or each study had to have one group that did a power type exercise where they form the concentric exercise very quickly. And the other group had to do it slowly on the concentric and both X on both groups, they lowered the weight under control. And, uh, we found the, uh, effect size was about 0.3.

19:49So it's a third of a standard deviation or so. Not a huge difference, but in my opinion, that certainly could be practically meaningful for an older individual who's starting to become functionally dependent in their, in their everyday living. Yeah, I've seen that, um, there's this famous study, uh, that I always point out, which was done on twins to show who has a better brain functionality. And it's the, the twin who was able to maintain lower leg power better than the twin who didn't.

20:20And it was directly proportional to how well they performed on cognitive tests and even down to how large their brains looked on MRIs. So I think there is a large component and a relationship between power, well, I mean, strength as well, but power, especially for longevity. Yeah, no question. Again, we mentioned earlier that, uh, falls when you, uh, when an older individual falls and breaks their hip, the mortality is, I think, 50% after two years and 50%, another really, uh, obviously, uh, mortality is a huge issue, but functional capacity, uh, quality

20:59life, I think half of the older adults who experience a fall, never fully recover their functional capacity. So the, the, what, uh, prevents that is power. You're able to re reverse the fall. And if you don't fall, you're not going to fracture your hip. Yeah. You know, we brought up Stu earlier. I love Stu. Um, he's been on the podcast is so incredibly well-researched, well-read. And it's funny cause he's like, he's now bringing out his own podcast, I believe, which is great because he's like, I just want to just clear the air when it comes to all of the misinformation.

21:32As you, you've probably seen on social media. I just, by the way, did Stu's podcast and we covered several myths. It was a myth busting podcast. Which I want to know because, um, you've said that the fitness industry has a misinformation epidemic. What is the single most dangerous lie being told right now about how to build muscle? Oh, there's so many. I mean, one of the things that I think is really counterproductive is that there's one best way to build muscle and to build strength and just to develop the body.

22:08Um, you know, that's kind of the influencer method is that you take off your shirt and you say, this is how I did it by my program. And, um, many roads lead to gains. There's very many, you know, plethora of ways that you can go about building muscle. Uh, the basics are got to train hard, you got to train relatively close to failure. As I mentioned, two, maybe three or up short, you got to be consistent. Um, and you got to train all your major muscle groups as a general rule.

22:41You got to get a total body approach other than that. Uh, I mean, then it comes down first of all, to N equals one. People respond differently to different things. Some people respond better to somewhat lower volume, somewhat higher volume. What are your goals? Do you want to be a bodybuilder? Do you want to be an athlete? Do you want to be just more fit? Uh, so there's so many things to take into account and certainly there's not one way to train. Um, what are some other things that are happening right now that you think you need to clear the air on? Well, I think one thing that's really counterproductive is the, um, is the promotion that you need to,

23:20or I won't even say promotion. I think it's just the thought in a lot of people that you need to spend a lot of time with resistance training that people won't have time to do it. Uh, now, again, if you want to be a bodybuilder, if you're looking at bodybuilding style workouts, yeah, you're going to have to put in more time in the gym, the higher your expectations, your goals, the more effort and the more time you're going to have to expend to get to achieve that. But for the everyday individual, again, 80% are not even doing any muscle strengthening.

23:50Two 30 minute sessions or so per week is sufficient to see substantial improvements. Substantial, substantial in multiple and strength and muscle development and metabolic health, brain health, et cetera, as long as you are training hard and as long as you're consistent. So you do it twice a week and you got to show up twice a week. I think the word hard is, um, is lost on many people, even myself. For example, I don't feel like I can go as hard by myself as opposed to if I had a trainer with me,

24:24you know, getting me to that last rep, whether it was assisted or just speaking to me. Yeah. I mean, a lot of people do think that, and again, it's, um, a lot of it comes down to motivation. You know, if, uh, it's, it's easy to say, ah, I've done, I did enough. And, but if your goal, and again, I come from a bodybuilder, I was a natural bodybuilder for quite a number of years when I, my younger years. And, uh, I would have eaten the grass off my lawn if, uh, that had told me I was going to get more jacked or more cut.

24:55So, but it was all motivation. So it comes down to intrinsically, do you really want to make the gains? And look, I'm not saying that you don't get anything if you're not training quite as hard, but to, to optimize results, particularly in the, in more, um, minimum dose type routines, meaning shorter, when you're not doing as much volume, you need to be training really hard. Or when I say need to, you're going to really compromise your gains if you don't. Guys, I am a big believer in testing instead of guessing, especially when it comes to your

25:27health. And for years we've been told to wait until something goes wrong before looking at our blood work. I mean, that's, that's what the medical system is right now. You know, you break an arm and you're in the hospital and that's great, but it never taught us how to get on track as a preventative method. And this is why I use function health because when you use function, it gives you access to over a hundred different biomarkers all in one place. They've got this amazing platform that you can look at everything.

25:59It tracks all of your biomarkers over time. So you can start seeing your patterns. And for me, the power is in the inside. So instead of wondering why your energy is off or your mood or your focus, or you're wondering if you're in perimenopause, you can actually see what's happening inside your body and make decisions for real data. Now, if you want to get some clarity and if you want to get your blood work done with function health, you can, you'll get a discount. If you sign up at functionhealth.com slash Louisa Nicola, or go to functionhealth.com,

26:33use code neuro 100 at sign up to get started. I think one of the other misalignments that we're seeing as well is the protein debate, the RDA, the 1.6 grams per kilogram of body weight is needed to activate muscle protein synthesis. Where are you sitting now on that, on that nutritional line of how many grams of protein you need to increase hypertrophy? Well, so the first thing we've got to talk about is whether you're talking about someone

27:06who's resistance training or not, if you're untrained. So when you resistance strain, you need more protein to build muscle or you can maintain. If you're not resistance training, you're not building muscle, but from, from a maintenance standpoint, the RDA is 0.8 grams per kilogram per day. Yeah. Uh, and that even that has been shown to be too low just from a maintenance, it's probably somewhere around one gram per kilogram, but yeah, the, um, literature that we have, I would say kind of the minimum threshold in my opinion, in my interpretation of the

27:38literature is around 1.6 grams per kilogram per day. I think there are some, if you're resistance training, if you're resistance. Yes. Okay. There is some, uh, muscle protein synthesis studies that show it can go up to around two grams per kilogram per day. Um, if you're in a caloric deficit and an energy deficit, so if you're trying to lose weight, it can be even a little higher. We have actually researched that's in review that does show that, uh, going above two grams,

28:10maybe to, to optimize, to order, prevent muscle loss in a, in a caloric deficit. But I would say if, as long as you're at maintenance or above slightly above, um, 1.6, I think for the majority of people, certainly again, this depends if you're a bodybuilder, I'd say you want to earn the side of caution. You go a little higher, but there's going to be inter-individual needs and everyone. When we research, we look at the means, the average responses. People are not an average.

28:41People are individuals and there's going to be variation around that mean. So again, for the average individual, I would even say if you're a little below that, it's just not going to make a meaningful difference. If you're 1.5, 1.4, probably it's, you know, we might, you're not optimized. Yeah, but it's, most people are not going to look at themselves and say, oh my God, I missed that 0.2 grams of protein. But if you're an elite athlete or aspiring to be, or a bodybuilder, or even just someone who wants to maximize their muscle growth, going a little above, I think is a good cost-benefit.

29:14Yeah. Uh, you know, it's not going to hurt you. I was talking to, um, I forget his name now, he was, is a scientist, a PhD, and he came on the podcast and he's done a documentary before on Netflix and he was telling me that he doesn't believe in the, um, the protein and the eating protein and that it's more, um, it's, we actually just only need the 0.8 grams. So that caused a lot of stir on, um, uh, on my podcast. And that's why we brought Stu in. And then Stu was more on the bandwagon of the stimulus is actually the most important thing.

29:45Like you can't just, yeah. Um, over protein, you can't just eat a hundred grams of protein a day and expect to build muscle. It's actually more stimulus. And so even if you have to bring it down to, let's say 80 grams a day, which is below your, your threshold, but you're still hitting the gym and getting that MPS at the gym, then that's the most important thing. I completely agree with that, that you can be deficient in protein and you'll still build muscle. But again, is it, what is our goal here? Is it to maximize muscle growth? So yeah, you're not going to max if you are at 0.8, just all the literature we have.

30:18I'm not sure how someone could say that if they're actually there are scientists and looking at the literature, all the literature we have show there's a much greater need for protein in those to optimize. It doesn't mean you're not going to gain muscle. You can gain muscle in a deficient state. So you can do a lot of things. You can train substandardly and still gain muscle. It doesn't mean that is optimal if you want to maximize. I mean, to me, again, I'm a former bodybuilder, so I'm somewhat biased in that respect. But even if you're going to, to me, if you're going to do something,

30:49you should at least try to get the maximum benefit within what you can do. And I don't see why there's very little to no downside of consuming the higher protein. I'm not seeing any literature showing that, uh, at even the levels are even higher levels, but certainly at 1.6 grams per kilogram, there'd be any health, health-related issues with them. Back in the nineties, you probably didn't see the rise of, um, the GLP ones, but now you're

31:19seeing that. Do you think that we've got a problem there with, um, maintenance and building muscle because of GLP ones now? I don't necessarily. Uh, it's interesting. You bring that up because I'm collaborating on a study, uh, see what happens, but that's going to involve resistance training where we're actually looking at, uh, MRI, looking at muscle development. Most of, I mean, the GLP ones where you're seeing this massive muscle loss along with the weight loss is without resistance training. So yeah, if you just, and by the way, any time you diet without resistance training,

31:54the literature we have shows around a quarter of each pound that you lose is from fat-free mass. Now remember this too, that's DEXA derived that we're estimating through DEXA, um, dual X, uh, dual X-ray absorptiometry. Um, that is not fat-free mass is not muscle mass. It's, it constitutes, there's a component of muscle mass, but it's all nonfat tissue. One of the primary tissues is water. So adipose tissue, fat tissue is 20%, 25% water.

32:27When you lose fat, you're going to lose water from the fat cells along with that. So that will show up on DEXA as a loss of fat-free mass. I'm not saying certainly there will be a loss of muscle mass as well. Now, one of the issues with GLP ones is that they intend to induce greater or more rapid weight loss. So you see weight loss instead of having, let's say two pounds a week, it might be three or four pounds a week. More rapid weight loss is generally associated with more rapid muscle loss. Uh, so that is an issue, but if you're counteracting that with resistance training,

33:02I'm not convinced there's going to be that big an issue. And, um, the other thing that I would say, and I kind of touched on this before, but having a higher protein intake during fat loss also has been shown to maintain more muscle. You know, the more that I hear and the more that I talk to people and study, the more confused I get. Um, but again, um, I've really just come back to, it's not rocket science, but we're complicating it. I feel like we're just complicating everything, going into the gym,

33:32doing a certain set of weights, because we're looking at somebody who does a certain thing on, on Instagram. We see the reels, we see this and we're like, I want that. And at the end of the day, it's just, it's something that we've been doing for hundreds of thousands of years. Right. You just go in, well, exercise, but we have, it's, it's literally just exercise. It's stimulus. That's all it is. It's placing load upon a stimulus for it to grow. I would completely concur with that for the general public. Yeah. And now, again, if you're a bodybuilder, then you need to more scientific basis.

34:08In my humble opinion, I don't think it's even debatable that you're going to need to focus more, not only on the science, but also in inter individualizing your, uh, your program, because you can't just use science. As I mentioned, each person is their own N equals one experiment ultimately. But, um, you need to micromanage your resistance training and your diet to a much greater extent. If you're that's your job, if your goal is to maximize your growth. So the, the higher, the closer you get to your genetic ceiling, meaning everyone has a

34:41hypothetical point where they're, they can no longer gain muscle. By the way, in my humble opinion, no one ever reaches that. No, it's kind of a concept because there's always different things you could do. It's no way to research. Have you actually gotten to your ceiling? And I've worked with very, very high level bodybuilders who've been able to add more muscle by just manipulating variables differently. But what I would say is the closer you get to your genetic ceiling, the more intuitive and insightful you have to be in doing things differently and manipulating variables to,

35:13to eek out the smaller amount of gains that you have left. Yeah. It's, um, I know that for myself as well. And then we also forget that real life comes into play, especially for women, you know, whether they're going through, maybe they're pregnant, then they're going through childbirth and their primary caregiver, then it's like sleep loss. And all of this adds up at the end. I want to go back to the power, the power versus strength, because I looked up your, um, meta analysis, uh, in JAMA network in 2022, looking at the explosive lifting.

35:44Is that the one that we discussed earlier? Yeah. We discussed that. I think what I find terrifying there is that, um, when we're looking at, you know, you look at longevity science, right? And yes, it's about sarcopenia and, and, and the loss of sarcopenia, but it's also related to, uh, osteoporosis, right? Osteoporotic, uh, fractures as we get older, especially for women in, you know, in their menopausal years, if they're going to get a hip fracture, we know that they're not going to

36:15leave the hospital bed, maybe they've got like a 30% chance of dying afterwards. And that's pretty scary as well. And so this notion of power is really important. I just want you to just walk me through what that might look like from a, an actual standpoint. If someone has 90 minutes a week to work out, what does power and strength look like in that 90 minutes each week? Yeah. So the art of programming is an art that is based on the underlying science. Uh, and that again can be done in some, there's not one way I can give you certain examples.

36:47That doesn't mean that is the only way to approach it. And so here's what I will say. You don't need to do all power training. Certainly. It's not like every set that you're doing needs to be explosive, concentric, and then control the eccentric. Um, some portion of that 90 minutes should be devoted to it. It could be done. Let's say you're doing three days a week, a half hour sessions, or two days a week, 45 minute sessions. You might do one day power training and other day strength training. You might do one X, uh, multi-joint exercise power and a single joint exercise strength.

37:23Again, there's just so many different ways that can be rolled out. And what I would say is that needs to. Be specific to the individual preferences are going to come into play. The most important thing is adherence. Someone doesn't like what they're doing. It doesn't matter. You can have the best program. If they don't enjoy the program, they say, you know what? I'm not going to do this. What good was it? So what I would say is as long as you are getting some strength-related training in, so it doesn't have to be hit. We talk about strength-related.

37:54It should be somewhat heavier if possible. Uh, probably six to eight to 10 reps, somewhere in that range would be. Now, if you're a power lifter, then you want to be doing one rep and three reps. Then you want to be training really heavy. But for the general public, the cost benefit there is not great. In my opinion, there is certainly an increased injury risk, um, spotters. And there's other things that can be problematic with training really heavy, but you're going to get the majority of your maximal strength gains training with six,

38:26seven, eight reps. Um, and then using some somewhat lighter loads, let's say 10 reps and just training more explosively on the concentric and lowering it somewhat slowly. One thing that you haven't mentioned throughout all of this is aerobic training. Where do you sit right now with that? And do you do any studies related to aerobic or anaerobic threshold training? Yeah. So I'm, first of all, I'm a muscle researcher, uh, and bias. Certainly I, if you're, if you would ask me, what is the most important thing you could

38:58do for your overall health and wellness, et cetera, I would say it's resistance training. But that said, I'm a huge proponent of aerobic training. I'm not an aerobic researcher. So we've done, I might've been involved in a couple of studies over the years that in collaboration that have involved aerobic training, but it's certainly not my focus. That said, I incorporate aerobic training. When I say aerobic training, I I'm a step count person. I really, I'm a big fan of making sure I hit my roughly 10,000 steps. Not like it's a magic number, but if I get somewhere close to 10,000 steps, a little more, a little less

39:33on a daily basis, I think I'm hitting a pretty good target for aerobic fitness. There is good research showing that, um, high intensity interval training can actually help to maximize, optimize cardiorespiratory fitness, your maximum aerobic capacity, which is linked to, uh, longevity. But again, there's a trade-off in terms of, uh, enjoyment, uh, high intensity interval training. That isn't necessarily fun. And I do sometimes when I'm doing, uh, my walking, as long as I'm not walking my dog,

40:06who does not like to run, but I'll do some, I'll throw in some sprints as I'm walking, uh, to try to kind of get touch on that aspect. But I don't think that the, uh, it's going to be hugely different in terms, at least from a longevity standpoint, again, if you're a, an athlete who's an anaerobic athlete, you're going to certainly need to do high intensity interval training or some form of anaerobic threshold training. You said that you're obviously, you're a muscle scientist.

40:39We've touched on the importance of muscle for different areas of longevity where, you know, as it relates to, um, you know, functionality and being able to get out of bed. But what are the other areas that muscle is contributing to health? Yeah, muscle, um, improves virtually every organ in the body, organ system. So first of all, metabolic health, one thing that's really underappreciated is that number one, having more muscle allows you to store more glucose. So metabolic disease, particularly diabetes or insulin resistance has to do with the inability

41:16to properly store carbohydrate in the muscle as the primary storage house. So you, the liver does store a little bit, uh, and muscles become insensitive. If you don't lift weights, you tend to become insensitive to storing glucose. And the more muscle you have, the more it's kind of a sink reservoir for storing glucose, you have greater capacity. So that in itself will help to reduce, uh, the incidence of insulin resistance to diabetes. But it goes beyond that. Um, um, resistance training itself helps to wake up what are called, uh, GLUT, uh,

41:53four receptors, which are inside the muscle. They're kind of chaperones. They function as chaperones that basically meet, uh, they go to the insulin receptor and they meet the, uh, glucose there to bring it into the cell. So they kind of chaperone the entry of glucose into the cell. Um, it's been suggested, at least some of the literature indicates that a lack of activity of these GLUT4, um, transporters will, uh, enhance the possibility of, or increase the possibility

42:26of insulin resistance. And, and even just at the receptor level, having greater affinity, uh, receptor affinity for allowing the entry of glucose. So on multiple levels, muscle is, uh, is a metabolic, uh, sink house. Mm. Would you say that that's the most important correlation? Cause I'm seeing, um, some, some great correlations between even immunity. Well, so there's certainly other, yeah. So immune function. So as I mentioned earlier, muscle secretes myocons, which, which helps with chronic inflammation.

42:59Yeah. Uh, so chronic inflammation has many negative effects on the body, including by the way, it diminishes muscle building capacity. So older individuals tend to have a lot of chronic inflammation. These, uh, cytokines and muscle secretes anti-inflammatory side, uh, myocons, which help to counteract this chronic inflammation. Talked about brain health, uh, brain level. Um, I mean, posturally that's, it's not necessarily an organ system, but at the spinal level, uh, so helps

43:34of course to, uh, uh, resistance training to give you greater, uh, improve your posture, which has not only effects on how you look and how you present yourself, but also on health overall. When you're stooped over, it actually, uh, saps energy and, and has effects. I actually feel like that's me sometimes just cause I'm always at my desk and I'm noticing it in my back and I'm like, what is going on with me? So now I've like been optimizing my lat pull downs as much as I can and the rows as well. I feel like you at 400 peer reviewed articles, right?

44:08You'd think what more is there for me to study? Oh, there's so much. Uh, so I, I mean, what I would say is we're still in the relative infancy of studying all the things that, well, basically, first of all, in your variables, not my primary focus is on variables, but I mean, we have almost no studies comparing, uh, so most of the studies that we have in variables compare, let's say, uh, heavyweight versus lightweight. We have very few studies that

44:39look at combining. I've mentioned the combination. I've carried out one, but you need, it's not like one study solves anything and you need many, many studies to really get confidence. Each study is a piece of the puzzle. So even just looking at clarity on a given topic for a single area, you need five, 10 or more studies to really start to draw confidence in your conclusions. And then again, going beyond that, there's just so many topics that haven't, in my opinion, been adequately looked at them. We have very, uh, poor, when I say poor, limited research on advanced training techniques.

45:16So various time-saving strategies like rest pause training, intracet, uh, repetition training, drop sets, uh, uh, uh, super sets. Like these are advanced training, uh, techniques that we have used handful of studies on them. And there's really, yeah, yeah. I know we like to think that we're in this enlightened age. Cause I'm saying like drop sets are like, uh, a really great thing to do. Well, and when you say great, the evidence we have now, so again, it's still quite limited. Uh, we did a mate analysis a few years ago on the topic. There was only six, I think there were five

45:50or six studies that actually met inclusion criteria. It's a very small maiden. Since then, there's been a few more, a couple more, but still in this, again, there's gaps because how you carry out that study is not, you're not just replicating the same study. You're carrying it in a different way. And it's, well, how does this fit in, in the overall literature? So you just need many, many studies to really draw a good insights. I would say the biggest, one of the biggest areas of interest is in mechanisms. Uh, we've come a really long way in understanding

46:24what drives hypertrophy, but it's very difficult to tease out mechanistically what is causing muscles to grow. Most, the vast majority of research on the topic are either in cell culture and test tubes, uh, which have, of course, limited extrapolation to humans or in rodents, which still have a little more than test tubes, but still have limited extrapolation. You're just not going to be able to do the things that are necessary to humans to understand what goes on. This episode is brought to you by IQ bar, our exclusive snack, hydration, and coffee sponsor. Guys, the IQ bar, the protein bars,

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48:42That's neuro to 64,000. Message and data rates may apply. So you're telling me in 2026, 400 plus papers, and we still don't have a definitive answer for what causes muscle hypertrophy? Well, I'm not saying that. I'm saying that we have a better understanding, but we still, there's many things we don't know. I mean- What do we know? We know that mechanical tension is the primary driver of hypertrophy. Right. Now, again, I don't think we have enough time to go take a deep dive into this, but

49:13mechanical tension are the forces that are acting on the muscle. Number one, there's active tension, and there's passive tension. So passive tension occurs during a muscle stretch, which is both either passive, or you can passively stretch, or even when you're, let's say, in the lengthened position of a movement, like a curl, if you're in the bottom position, the muscles are under passive tension at that point, even as your act. So there's a combination of active and passive tension, which contributes more how much we know that both do contribute. Is there an optimal way we can utilize

49:47these concepts? Um, we don't know if to the extent to which other potential mechanisms may contribute. So, um, I wrote a paper for my capstone project in my master's program, 17, 18 years ago now, which was published in the Journal of Strength and Condition Research. Um, where I kind of took a stab at what the mechanisms were at that time, what we knew. And I, I talked about mechanical tension,

50:17but also metabolic stress and muscle damage. And we've gotten more insights that certainly these alternative factors have less relevance, certainly than I think the literature had suggested that it might be at that point, but we still don't have great evidence that there's no contribution to it, or if there is, what is the contribution? Um, and maybe there are other factors that, that are involved. So, um, again, it's not, it's not an either or, do we have knowledge or not, but it's the

50:48extent of the confidence in our knowledge and saying, this is where we're at at this point. And so I'm saying the needle has gone a little over back when I did my paper, it was very weak evidence. Now we have stronger, but still in my opinion, fairly weak, it's maybe more towards the moderate. And, uh, I don't have a lot of, I have a lot of confidence in saying mechanical tension is a primary driver. I do not have a lot of confidence in saying there might not be other factors, mechanistic factors that also do contribute in a synergistic fashion.

51:22What are you confident? You mentioned that you have to have, you know, uh, replication, I guess, and not just replication of studies, but like a large body of work to suggest that one thing you can confidently say that this is true. Like you mentioned with, um, a certain area of, of hypertrophy and mechanical tension. What other areas have you explored that you can definitively say, okay, I've, I have high confidence that this is true. Yeah. So we talked about one is the fact that light loads build muscle, very high confidence.

51:52I'd say I have, I there's at this point, there's been so many, we have dozens of studies and they all show no difference. Basically they're all when I said, well, almost all right on the needle. There's a few kind of somewhat outliers, but I don't say in my opinion, I can't see it would have to be so many studies that just show something different, which is so unlikely. I think we'd have a greater chance of seeing a landing on Pluto at this point than we do of getting, uh, you know, evidence where the

52:23lighter loads are less effective than heavier loads on a whole muscle level. Yeah. But even within that, as I mentioned, there's much less evidence is there may be a specific effects on fiber type. So even though we know on a whole muscle level, it's when we do MRI or ultrasound, we actually look at the size of the muscle as a whole. We're not looking at the fiber level. The studies on the fiber type level have been somewhat mixed. And there does, there's at least suggestion that there may be type one, uh, fiber hypertrophy with lighter loads. And when I say it doesn't mean you

52:55don't get type two, which just means there might be somewhat greater hypertrophy in type one fibers and somewhat greater hypertrophy in type two fibers, which would mean that conceivably combining them. So this is where, again, you talk about even in a given topic, you might have a lot of confidence in one aspect of that topic, but other aspects might be lower on the continuum. What is your stance now? And we mentioned it briefly on rest intervals. I think that's probably the hardest thing either. Um, uh, we're resting too much or we're not resting enough in between sets.

53:28Yeah. So we're talking about for muscle development, muscle hypertrophy, another area where I've somewhat changed my opinion on, um, we carried out a mate analysis on this topic. We've carried out a lot of mate analysis. And what I would say is, is that the literature at this point shows that if you're resting very, have very short rest periods, like 60 seconds or less, you will compromise muscle growth. Whereas once you get up to around 90 seconds, it seems there's not much difference between 90 seconds and more. But even with that said, you talk about the confidence. I don't have

54:02great confidence that that's the case because number one, there aren't still that many studies on the topic. The mate analysis had, I think nine studies, which is not, yeah, not, it's not a lot at all. And the, there was heterogeneity and the methodologies. So trying to pull the data, you do have some skepticism in terms of the conclusions you can draw. I would say that to me, at least where I'm at now, probably on single joint exercises, less complex exercise, like machine training, 90 seconds

54:34or so probably is going to be somewhere in that range. But if you're doing squats or deadlifts, probably two minutes or perhaps more might be needed to fully recuperate. But why is it that if we go over, let's just say you're having five minutes between sets. I mean, I don't know who has time for that, but let's just say you are for argument's sake. What's that doing? Well, so the, the seeming issue with short rest interfering with hypertrophy is that when you rest very short periods of time and you then go back and do another set,

55:06you're going to have to lower the load a lot more because you're still going to be fatigued. There's residual fatigue from that previous set. So you're either going to have to make the weights lighter to get the same amount of reps, or you're going to have to do less reps with the same amount of load. Whereas if you rested two minutes, you'd have more recuperation. There doesn't seem to be much benefit beyond around two minutes or so. And we have some data coming out that I think is going to show that even more. But is it detrimental? No, it's not detrimental. Well, it's detrimental from a cost benefit if time is a factor. So whereas,

55:39is it detrimental to rest longer? Detrimental to hypertrophy itself. To rest longer? Yeah. No. So you could, if you had time, do one set, rest for five minutes. Do another set, rest for five minutes, if that's the way you wanted to train. Rest for 10 minutes. Wow. But again, most people, the majority of people, time is a primary barrier. Yes, of course. So I think one of the things we want to emphasize is that you don't need to rest long periods of time to still maintain, still get the maximal benefits. But, uh, yeah, I mean, most, many people do their

56:14cell phone workouts. So I'll give you a scoop here where the study we're carrying out now, you know, we haven't analyzed it yet. So I can't give any, um, insight into muscle development, but we looked at one group who rested two, two to three minutes. So fairly sure, you know, we're kind of within the guidelines of what's optimal. The other group, we let themselves select their rest intervals. What was their, um, sets and reps? So they, we told them just come back whenever you feel you're, um, you're ready to train. And here's the thing. We took away their

56:45cell phones. We did not let them use it. Oh my gosh. So we're, there was actually a better, uh, we got better insights into their actual recovery. What they felt was the recovery needs. They ended up resting over a minute longer. So whereas I think it was 2.3 minutes in the, uh, uh, average rest in the group that we've had fixed rest intervals, the rest of like 3.6 minutes. So like 1.3 minutes more. Uh, and I'm sure if we had to let them use their cell phones, it would have been five or more minutes, you know, they get lost in space in terms of texting.

57:19Oh yeah. Yeah. That I've actually got a new rule now. So, um, I lock my phone when I go to the gym in terms of, I take my phone with me, but I've got this specific device that locks me out of Instagram, my Gmail and my text messages. So, and it's such a natural thing because between sets, I do touch my phone to try and go into and it's locked. So it's like this habitual thing that I'm used to that I'm now breaking out of and my workouts are so much better and more enjoyable. And I'm actually there instead of thinking about work. That's great.

57:50Yeah. I am obsessed with that now. Um, I want to just keep, I just want to know more about what other conclusions that you've come to over the span of your entire career, because you're up to the third edition of your book. So I'm pretty sure that there's other things in this book and the third edition that you've covered that you probably didn't cover now that you have all of the available evidence. Yeah. I think one of the, another really interesting thing that is, uh, we've gotten quite a bit more insight to over the past decade or so is the importance of the length and position

58:22during resistance training. So you'd see a lot of people work out and they'll do like a shoulder press where they just do it in the short. They'll do like a little half rep in the short. So not full range of movement. Yeah. And what we found is, is that even if, so the, it doesn't even have to be a full range. The most important part, if you're going to do a shoulder press, if you want to do a half rep, do it from here to here. So the first, the initial portion to like the mid portion is the most important, at least in most muscles that we've studied the most important, uh, portion of a movement. And there's quite a number of studies. Now the majority of literature shows that if you

58:58just do a half repetition in the length and portion, it's as effective as doing the full range of motion. What? Yeah. But, and it's much more effective than doing, uh, if you do just length and partials, versus shortened partials, the length and partials get much better, uh, hypertrophy. Is that just, if we're talking about deltoids? No, no, no. I just use that as an example, but no, we have actually, we don't even, to my knowledge, it hasn't been studied in the delts, but I mean, the majority of evidence we have are in the biceps,

59:28the triceps, quads, the hamstrings, and the calves. So in the limb areas, it could look, there could be muscles that, that we just don't have evidence of it, but it might be certain muscles are more predisposed to length and training than others. But the evidence that we have virtually the entirety of it in the muscles that we've studied, which is limited generally to the limbs, seems to show a benefit to the length and position over the short position. Like if you're doing a bicep curl and you're doing the half range of movement,

1:00:00you're looking more at the biceps head at growing. Like if you, if you're just doing. Correct. Yeah. So the, probably because of the mechanical tension placed upon that. So we go back to the passive and active tension. There's greater passive tension in the initial phase. So look, there could be a, this is just speculative. That's why studying mechanisms we can study. Hey, if you do this versus this, what's going to produce more hypertrophy, trying to figure out what is causing that difference. You know, what's responsible for the

1:00:30differences in growth is much more difficult. That's not, we can speculate based on theoretical knowledge and, uh, that, that does drive hypotheses, but trying to actually, uh, understand that in vivo in the living is much more difficult. There's a difference between feeling functional and feeling like yourself. And most women I work with are operating, but they're not at their baseline. Their sleep is slightly off. Their mood is slightly unpredictable and thinking isn't as sharp as it

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1:02:06you will get 32% off your purchase. Biologica.com slash neuro to get up to 30% off your subscription. The hardest part for me to train for some reason is always my, uh, my, um, triceps, but also rear delts. I wish I could just, I wish I could just get there and do my bent over rows. And I don't know why it's just, this is for some reason, I just can't get my head around it. I don't know what it is. You know, with different people, the one thing I'll say is that, um, everyone has things, areas that they

1:02:39enjoy training more, uh, and they're more in tune with like mind muscle wise. Uh, I always had, oh, and I say always, when I initially started training, I had difficulty with my lats, trying to engage my muscle and really feeling the contractions over time with practice, I was able to do it. But a lot of it is just practice and you gotta try to will it away. Yeah. Have you seen, so there is this little at home machine that I'm thinking maybe I should, maybe I should get that. And basically it's a, it's this machine that adds load to, it's just got a, it's just a

1:03:14pulley machine. Okay. And it comes with a bar and you can just be sitting there at home and you do this and it's actually got weight on the eccentric and on the concentric phase. Have you seen anything like that? This new, I don't know, you can actually click it. I wish I knew what it was called. You can like hang it anywhere and, um, it just provides more load, um, as you're pulling the thing. So basically you can work out anywhere if you just take this with you. If, if I am understanding what you're saying, there is the, uh, some devices that use electromagnetic

1:03:47technology and that can be very effective. Yeah. Well, anything that adds resistance, you can get resistance bands. Now there's some limitations to bands because then the, um, when you're doing the initial phase, there's not as much tension, tension actually comes more in the end phase, which is somewhat of a detriment to them, at least when using them as a standalone. But, um, certainly they can help you if you want to travel, put them in your suitcase and you can use them. But yeah, the electromagnetic can be a very effective technology. Did you know, well,

1:04:19here in New York, that there's this, um, place that's open. I know this because I have, I have a client who's 62 years old, female, and she has started, she's got this trainer who comes to her house and puts a suit on her, wets her, puts this suit and it's electromagnetic simulation. And she says, Louisa, it's so hard. What I get done in 20 minutes, the trainer told me that I'm getting done like three or four hours of resistance training within that 20 minutes. What's your stance on that? Yeah. So I think you're talking about, uh, electrostimulation, which is different. The

1:04:51electromagnetic technology from re so you can have resistance that's using electromagnetic technology. But I think what you're talking about is, um, is electrical stimulation where you put on the little electrodes. Uh, there's, it's an area that I've become quite fascinated with because I used to kind of dismiss it. And first of all, it used to be promoted for like zapping fat. They had like the ab belts that would have that. And that doesn't do that. But we, I used the, it's like a tens machine, right? When I was a triathlete before, like when we would have to travel, like even like interstate, we would put it on our legs

1:05:25so they wouldn't atrophy. Yeah. So that's what I was going to say is that from a muscle building standpoint, the preponderance of evidence now seems to suggest that certainly as a standalone, if you're not doing anything, you can build muscle and we definitely need more. That's another area. We definitely need more research when you combine it with lifting weights or doing resistance training. But the limited evidence that I've seen does seem to show that it's additive, which is a really interesting, uh, concept. Now, again, I, I'm still, I'm a, as a scientist, you're trying to be a skeptic, but I do think that it's a worthy area. It's something I'm looking to,

1:06:00to study at some point. What's your take on, um, cold plunges after lifting? Yeah. We did a main analysis on this. And, uh, if your goal is to maximize muscle growth, you should stay away from cold plunges. It, it actually hinders hypertrophy. Um, and, and the reason seems to be, again, mechanistically, uh, somewhat speculative, but it inhibits blood flow to the tissues. Cold, uh, tends to, um, as opposed to dilating, restricts the, uh, vessels. And how do you get muscle protein synthesis? You get it through nutrient

1:06:33delivery through, through the blood flow, through the, uh, circulatory system. But it's most important straight after, like to not do it straight after, but if you wait three hours. Well, that's not clear. We don't have any evidence on that. So first of all, here's what I'll say. So that might be the case, right? The, um, evidence that we had was within 20 minutes post-exercise. Oh, okay. Muscle protein, the muscles are sensitized to protein synthesis for 24 hours after a workout. So if you, at any point, if you do a cold punch, you're still going to restrict

1:07:04your blood vessels. If you're going to ask my opinion, I wouldn't want to put that to the test. If I'm a body builder, uh, I would tend to think that it's not going to have a good effect. And by the way, on the other hand, we just finished a MAID analysis on heat, post-exercise heat, and that had somewhat of a positive effect. It was very modest. Um, but it certainly didn't have a negative effect and heat increases dilation of blood flow. So at least, uh, logically, there would be the alternative to cold punch. I think that's where the biggest benefit of

1:07:39saunas come in. Correct. Yeah. But not if you're optimizing for hydration, obviously. Yeah. There's going to be, we look at things in a vacuum, you know, and there's going to be a, you always have to look at the totality of what other things might be influenced and then make a decision. What, what's important to you. Have you done any, anything on sleep and, and muscle building? So it's interesting you ask. I do have a new, not a chapter, but a section. I did a whole section on sleep in my, in the third edition of my book. Um,

1:08:13and I also am a coauthor on a paper that has been submitted to a journal. So, uh, it was a review paper. So we'll see, uh, hopefully that'll be published soon, but look, sleep, um, if you're asking, is there a lot of evidence on it? The evidence we have is somewhat difficult to draw good conclusions on because we know that there's a lot of, or at least a good number of studies on deprivation where they'll, and a lot of them are in animals, by the way, like in humans, there's some,

1:08:45you have a few, but the overall sleep deprivation where you get like 24 hours, no sleep. Yeah. There's negative effects on muscle protein synthesis. Um, there's not good evidence while we talk about like seven to nine hours sleep a day is optimal. That's in my opinion, that's, first of all, it's certainly not based on a plethora of evidence. It's based on an extrapolation of what we think. Um, and my thought would be that it's probably inter-individual that we can't, you know,

1:09:16that some people would be able to do well. I think there's going to be a minimum threshold that certainly should be at some point. What that is, is it five hours? Is it six hours? And then too much sleep? Is it nine hours, 10 hours? Who knows somewhere? I think the restricted zone or recommendation is a little too, at least it may be the case. I am skeptical again, that we can hone in and say that everyone needs this exact amount of sleep. Um, but, uh, the evidence that we have within fairly wide limits doesn't seem to show, even if

1:09:50the, there was a study done showing that restricting from two hours of normal sleep, I think it was where they had them do two hours less than normal, did not affect their muscle development over a, I recall an eight week study period. Would the biggest, um, correlations for this be, uh, growth hormone secreted during deep sleep, or is it more so about like, if you've slept more, you can push harder the next day? Yeah, I doubt the growth hormone has that much to do with it. First of all, growth hormone. Um, while the name sounds like it's a

1:10:22real muscle building, uh, hormone, it really is more, it's kind of a hybrid hormone, but it has greater effect, at least on the evidence we have in lipolysis in breaking down fat tissue than it does. It's more of a quote unquote cutting hormone. Um, and in physiological levels, I'm not, again, I can't rule that out, but I don't think it's, has that much prominence in muscle building, where it would have that big an effect. And by the way, how much is growth hormone suppressed if you, let's say, sleep five hours instead of seven hours, six hours instead of eight hours? I'm

1:10:55skeptical there's that much difference. But yeah, my, at least my speculation would be that it has to do with you're not as ready to go. You're not as prepared for your workout. You don't have the mental acuity to really push yourself. My last question to you is, I'm, I'm so excited for your book, by the way. Thank you. What's the most exciting chapter in there that you've written or the most, uh, something that, um, that probably people haven't learned about yet that they should look

1:11:25forward to. So I'm the author. I think they're all exciting, but the one I'm most proud of, I added another, I added, uh, a new chapter. So I added a lot of other sections in the book and a lot of sidebars, et cetera. And of course, uh, a lot of new information. It's like 30, 40% new information. But what I'm most proud of is the first chapter is on evidence-based practice. How do you, what is evidence-based practice? How do you take research? You know, I don't, I, I've written a

1:11:57book and a lot of people I don't think understand, understood how to use it properly. And I went through the whole process of here's the evidence, uh, here, here's go from mechanistic to, um, applied evidence. And then how do you then take that and use your own personal expertise and needs and abilities of an individual, um, talking about statistical analysis, what mistakes that are made. And, uh, anyway, I think it's going to be very enlightening. I'm going to link it below. Brad, thank you so much for coming on the podcast. It was my pleasure.

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