Metabolic Fitness: Considerations of Fasted Cardio & Muscle Growth ft. Dr. Brad Schoenfeld

Metabolic Fitness: Considerations of Fasted Cardio & Muscle Growth ft. Dr. Brad Schoenfeld

Authored by Zhill Olonan and Geoffrey Woo • 
April 29, 2019
 • 37 min read

Dr. Brad Schoenfeld is a natural bodybuilder turned research scientist whose work focuses on the mechanisms of muscle hypertrophy. Simply put...muscle growth!

Unlike most of our other guests, he’s more cautious on the applications of the ketogenic diet and intermittent fasting, which we wholeheartedly welcomed. This is an evidence-based conversation that unpacks various nuances around the interconnected network of metabolism and physicality.

In this discussion, you'll discover...

  • The ketogenic diet & intermittent fasting on muscle growth and what considerations there are
  • Resistance training vs. ketogenic diet - What has the most effect on insulin resistance?
  • Discussion on protein leverage hypothesis, anabolic window, & fasted cardio

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Transcription

Geoff

Dr. Schoenfeld, thanks so much for coming on the program.

Brad S.

My pleasure.

Geoff

So perhaps to frame the conversation before diving in. I personally got interested in the human performance space broadly more from a fasting, longevity, cognition perspective. Obviously you've done a lot work, and published a number of interesting research papers on the broader human performance space. But I want to get back how you even got into the space. I know you've been an award-winning body builder. Curious to hear your personal story of how you got into the research space. Did it come from a personal interest of you becoming a champion body builder? Or was this always academic intellectual interest, or a bit of both?

Brad S.

Kind of a bit of both. It came about, both my parents were physicians. My father in particular had a very big influence on my early thinking and discussing the scientific method with me from the time I was ye high. But it really throughout my earlier years, it was in the back of my mind, but never really came to fruition. It came about I would say mostly from a bodybuilding standpoint because I started to see that using the routines of my favorite body builders was not the way for me to get maximum muscle. That might have gotten them maximum muscle, but I didn't have their genetics, nor their pharmacology, if you will. So I decided, I started looking, how can I better optimize my own genetic capabilities. That ultimately led me to research. The more I started delving into it, the more interesting I got in it. It was just kind of one of those things that snowballed. It was a very nice match.

Geoff

Out of curiosity, how does one, how did you get into body building? I think growing up, people look at football or basketball or baseball as typical pursuits of athleticism, obviously bodybuilding is not unpopular but I wouldn't say it's the mainstream sport that you might get into growing up. How did you get into it?

Brad S.

It really came about because I, it's kind of a typical story that I was this really skinny kid, just very unhappy with my physique. I didn't ever think about going into bodybuilding, I just wanted to develop my physique, once I started to train I started seeing very large differences in my body initially, so I responded well. Over time, coming from where I was this skinny kid and started to see my body evolve, it just kind of became a- I don't want to say a natural progression, but something that started getting into my mind that, hey I was this skinny kid now you kind of want to prove to yourself that hey I can do this. Other people started to- I started making friends with some people who were competing, they started motivating, giving me inspiration really and I became motivated. It's one of those things, it wasn't an "aha” moment I just kind of evolved.

Geoff

Right.

Brad S.

This is something I really, the more and more I started getting into it, the more and more I started seeing its something I want to do.

Geoff

Yeah, and then again just on the personal trajectory side, obviously as you mentioned the pharmacology side of bodybuilding obviously a lot of people are having added assistance with different consumables, injectables all of that. What was your personal process thinking through the risks there and why did you go your path of staying more on a natural path?

Brad S.

I've been very pragmatic my whole life and everything to me is cross benefit plus reward, I just did not see a good cross benefit ratio to drugs. I have nothing against people that do, I've worked with many pro bodybuilders, that's why I don't make any judgements. Just for myself, me personally I just didn't think the health risk... I was never going to be Mr. Olympian, even if I was to get to that level the extent of drugs you have to take. But, to win local shows, even national level shows because it's nothing. If I was going to be an elite pro wrestler, athlete, or something where you're making millions of dollars I can't even say, I'm not in that realm. Maybe different, I would've thought differently I don't know. I was never, that was never presented to me, but certainly for me I just never saw this as a very good risk reward. The health risk, and there certainly are health risks associated with it, they were not good trade offs to looking good for a given period of time. Particularly when those attributes go away quickly once you stop.

Geoff

So, obviously that leads into the natural research areas that you've been prolific in. Hypertrophy okay, the practice of making your muscles bigger. So, translating from more of a practitioner, an athlete, a competitor in Hypertrophy to being a researcher in Hypertrophy. Tell us how you made that transition, what were your initial research areas into that specific physiological aspect of human performance?

Brad S.

Yeah, so I was a personal trainer for many years. I think one of the reasons my research has become so popular is because I'm researching everything that as a personal trainer, I wanted to know. I'm saying, well why isn't this research out there? And that's resonated with a lot of fitness professionals because, if I wanted to know it as a fitness professional so do they. I think most of the people in the field don't go through that progression, I was a personal trainer for 18 years, so I worked with all different demographics. From the highest level athletes, many bodybuilders all the way to geriatric individuals and young adolescents and everything in between. House wives, stock brokers, just any and every demographic population you can think of I trained, and it gave me this wide experience and understanding of responses in the human body.

So, my trajectory from there as I, like I said started getting really interested in training. While I was a personal trainer took a teaching position at a vocational school for personal trainers. Once I started teaching I just said this is now my course of what I want to do. That was where a light bulb basically went off, and while I did love being a trainer for the time that I was doing it, and by the way I still do consult... Have very limited clientele at this point, but I still like to keep my feet in the game.

But, I only do it at elite levels, like with people who are high level bodybuilders, physique athletes. The personal training just was a huge factor in my life, but it just progressed to the point where I got into teaching. Then once I got into teaching I said now I want to go on and become a professor, then I started realizing that research was a real focus of mine. That it was something I really wanted to do, so they kind of went hand in hand. It would take a couple of hours to go through the whole trajectory, so that's kind of the short course, but once I started teaching I just knew that was what I wanted to do, and ultimately went back to my PHD after that and got my professorial job.

Geoff

Very cool. So, what would you say are the biggest misconceptions in the personal training application for hypertrophy that you see out there? Given your practical, clinical experience working with athletes, then also your research background what do you think are the top 1, 2, 3 misconceptions that you'd like to clear or put out there?

Brad S.

I think in the general public the misconception is that just go to the biggest bodybuilder and ask them what their routine is, look I fell into that trap as well. That, hey they have to be getting big for a reason, and it's true look I'm certainly not diminishing that bodybuilders are... They're doing stuff right or they wouldn't be as huge as they are. But, it's also important to realize they have, as I mentioned very good genetics and very good pharmacology. If you don't have that going to the guy with the 50 inch chest and the 22 inch guns, is not going to get you his physique. So, that to me is something that is unfortunately still permeates the field particularly with those who were just starting out. Even with the many high level bodybuilders.

And, when I'm saying this I'm not... Want to emphasis that bodybuilders, you're never going to get research that targets that population to the extent that you would want. Like I said I worked with many, I've worked with some of the top pros. I'm working with a pro right now bodybuilder getting him to his contest, and there are things you do that you're not going to learn through research. Just because we don't study that, the generalized ability of the studies we have do not necessarily relate to that population.

Geoff

Or the individuality of each specific athlete, right? Like, when you do random I control trial this is a population level study, but when you're talking about specific elite athletes there's obviously unique different bio chemistries between you and I, and the professional athlete and a person on the couch.

Brad S.

Obviously there's huge individual variations, by the way that was going to be my next one which I'll get into. But, just when we're talking about studies that are carried out with trained individuals, which I carry out all the time they are not elite bodybuilders. Elite bodybuilders are closer to their genetic ceiling, they have usually... Obviously their genetics generally are much better. They have incredible drives, push themselves past where... So, there's just so many factors that go into it that you don't, that you have to take into account that researchers... So, basically... And this is where I was going to get to next, I think another misperception in people that are research based if you will, or evidence based is that research is never going to tell you what to do. Research only provides general guidelines to giving you a ball park as to where to start at, in terms of exercise prescription. Then it's always going to come down to using your expertise, then looking at the needs and abilities of the individual to formulating a customized program.

So, I think that kind of takes us from the total novice general person who just follows the bros, to the people who pretend to be more evidence based but don't really grasp that you're not going to get what you want. Research is not going to say, hey I'm going to give you the 10 commandments of how to train at this point, you just do this. That is, the evidence based approach is a three pronged approach that looks at what the best current evidence is, then needs and the abilities of the individual, and your expertise. That is really the art, that's where you're bridging the gap between science and practice. That's where the art of prescription comes in.

Geoff

Right, so when you look at a specific client or specific elite athlete, your genetics that's not something we can control at this time. Maybe, in 20 years you can crisper people then you can actually alter their genetics, but at current status quo you're not really touching peoples genetics. What you can control, and what you can manipulate is their exercise protocol, both the types of workouts and types of recovery that you do. I would say the second component is diet, nutrition, supplementation, or potential steroid pharmacology. When you work with clients how much is weighted towards the former, the interventions in terms of exercise and recovery and how much is weighted toward diet and nutrition? Obviously it's going to be a bit of both. Would you walk through how you would approach both of these levers in terms of optimizing an elite performer?

Brad S.

Yeah, when you say walk through you'd go through a... You find out what the person's doing. So, I'm the nutritional consultant for the New Jersey Devils hockey team, and kind of the same thing now when you're... The most important thing is creating a program that they're going to be willing and able to adhere to. So, bodybuilders usually are the easiest population to work with in that regard, because you tell them how to train and how to eat. You tell them that this is going to get them in their best contest shape, they're going to eat grass of the lawn if you tell them to. They're going to train however they are instructed basically.

Whereas other athletes it's much more, it gets harder. First of all with a bodybuilder, training and nutrition is everything. Their competition is a one shot really non-performance, but it's not really an athletic performance. Whereas if you're coaching athletes, like I do with hockey players, they're getting creamed in the games so they have game time. There's just all sorts of other confounding issues that are going to get intermingled in with their training, and their nutritional regimens get thrown off out of wack sometimes being on the road. So, again it's really hard to give you a cookie cutter on that because it's just very individual. But, you would be looking at, like I said looking to research... I'd be training obviously if you're looking at an athlete they're going to be, that's much more sports specific. Whereas a bodybuilder, if you want to talk about her tribute specifically, that would be where the muscle development and fat loss are par. That's what you're going to be judged on, so low body fat and high muscle.

And, you're just going to look at what the sport entails then understand how the general plan based upon what you know through research, and what you also know through your workings with individual athletes. Like I said, research has limitations with high level bodybuilders and high lever athletes in general, certainly with bodybuilders. So, there's going to be a lot of nuances there that's why having worked, there are people dismissive, but having worked with bodybuilders extensively is a very important factor I believe in terms of getting people into their best contest-

Geoff

Yeah, perhaps I gave an overly broad question there. So, maybe to make it a little more specific I think if you look at the bodybuilding sort of bro science millueau lot of people talk about eating six meals a day, never be hungry, have a lot of high protein, be lower on carbs, lower on fats. Then I would say within the last three, five years there's an uptick in popularity of the ketogenic diet, maybe some intermittent fasting, maybe do some fast workouts before loading up on more of a protein and higher fat content diet. Obviously there're applications for any specific diet for any number of indications, but perhaps specifically for Hypertrophy given your experience can you kind of give us the pros and cons of a six meal a day type of protocol, versus a intermittent fasting 16 eight lean gain sort of protocol? Or, what sort of protocols have you seen become popular in the bodybuilding Hypertrophy world?

Brad S.

Well from a fat loss standpoint there really is no tangible benefits to more frequent meals. Certainly to have more than three, and really no good evidence that there's any meal frequency that would be optimal for fat loss. You can lose probably similar levels of body fat at almost any meal frequency, and that's where intermittent fasting works certainly fine for that. I am not a fan of intermittent fasting or ketogenic diets for maximal hypertrophy and optimal muscle building standpoint for somewhat different reasons, the intermittent fasting limiting... If you're going to limit, lets say your food to eight hours that means that for 16 hours basically you're going to be catabolic. Or, lets say you're eating at the edge of that eight hours, so at that eight hour the anabolic effects of a meal are going to last, lets say five hours. So, at best you're at 11 hours of catabolism where if you're eating, you want to be anabolic all the time you can shorten that window, and how much difference is that going to make?

Well, if you're a bodybuilder if could make a difference. If you're the average person, it's probably more going to, so again now its context dependent. If you're asking me for the average individual that just wants to gain some muscle and work out, I think its ketogenic diets, intermittent fasting, low fat. Really almost anything is going to work provided you're managing your calories properly and that your protein levels are on target, that's going to be the essential. From muscle building standpoint, like I said the intermittent fasting spreading out your protein intake across the day, particularly the protein aspect. So, having at least four protein based meals from a muscle building standpoint would optimize your anabolic potential if they're spaced out every four to five hours. Then you're at your anabolic windows, if you will, where you're going to keep your body anabolic throughout the day. Throughout much of your sleep, depending upon when you're going to eat your last meal before sleep.

And, of the ketogenic diet the issue there is that glycogen, and these by the way both of these are not well studied. Certainly, like I said for the average individual it's probably not going to make a great deal of difference, but the issue with the ketogenic diet and there's some evidence of this in the literature, just not much research on it in general. Glycogen is an energy sensor, so a primary catabolic pathway is called the AMPK pathway I'm not sure how-

Geoff

I was going to actually follow up with some questions about that, so perfect.

Brad S.

AMPK is a catabolic pathway, it's an energy sensing pathway. When glycogen levels are low AMPK is going to tell them to get raised. Now, there's a lot of issues in terms of research on AMPK anyway, but just at least conceptually it's going to put you in more of a catabolic state because the purpose of AMPK is to initiate catabolism to bring your energy state back, meaning to raise your glycogen. So, basically it's going to, will often tend to impair the initiation of mtor, which is an anabolic enzyme, and thus just that in itself would tend to lead you to think that it's not going to be the greatest for muscle building. And, look the 80% of a bodybuilding style routine is fueled by glycogen, intermuscular glycogen.

So, when you're going to substantially deplete glycogen as you do in a ketogenic diet you're not going to have the energy, if you will, to fuel the workouts as well. Not that you can't get through a bodybuilding workout, but just that your performance would tend to suffer. There's been a recent study that it shows somewhat less muscle growth when they had a ketogenic diet, fat loss was similar but ketogenic diet did not promote as good growth of muscle. These diet studies are very difficult to carry out, I'm always somewhat skeptical because you tell people to do certain things. We can control a training study when people are there, and how they're training. When we have a diet study...unless you're in a metabolic ward and you're telling people what to do, adherence from my personal experience and from what I've seen in literature as well, it just is not great.

Geoff

I completely agree, I think you look at a lot of the epidemiological studies its just like people are reporting like 1800 calories a day, which is clearly they're not eating 1800 calories a day.

Brad S.

And not even epidemiologic, I'm talking about randomized controlled trials where you put someone on a diet. I've done this, running these studies and you tell them what to eat. With ketogenic diets it's a little easier to tell whether they're doing it because you can measure the ketone levels at least. To get some insights it's kind of hard to know what the other, you also not knowing what the calories are so... Anyway, these are just confounding issues that make drawing tactical implications, practical entrances difficult.

Geoff

Yeah, no I think you bring up a good point because usually we bring a lot of folk study insulin resistance, low carb diets, and an application of diet nutrition for longevity or pre diabetes or neurological conditions. I think you're adding a refreshing angel here that there's not a free lunch, if you are inhibiting MTOR, which is an anabolic pathway... Which that might have good applications for longevity, or metabolic syndrome applications, but if you're looking for athletic performance or bodybuilding or Hypertrophy applications then that's the trade off that you're making. So, if you're trying to be the most jacked person ever that's a completely different goal than I want to live as long as possible. Potentially minimizing my functional strength in my health span.

Brad S.

If I can interrupt here too, I'd add two things. Number one, this is not my area of expertise for longevity angle, but I have look at some of that research. I think it's very, I'm not saying it might not pan out, but I think that people are drawing implications from research like on spar fish. The generalized ability to, humans I think is very tenuous there, that's number one.

Number two, the other thing when we talk about metabolic syndrome etc you also have to remember that resistance training, and exercise in general, resistance training in particular has profound effects on improving insulin sensitivity. Probably even more so than, obviously diet is very important there, but both in terms of sensitizing the insulin receptors, and also your glucose transporters, which are what bring the glucose into the cell. Those really tend to be the issues, now if you have full blown diabetes, type two diabetes... Again, I'm not, this is somewhat outside... I'm not a clinical exercise physiologist I'm a performance, I'm a strength and conditioning specialist and performance enhancing.

But, I'm certainly familiar to a good extent with that research so it's a spectrum and I think people like to have binary, often they look at these... Someone's insulin resistant you have to look at the research that's come out in most of these studies, where they're looking at benefits. Let's say, the keto diet on insulin resistant people do not have a exercise component with them. That's a pretty big factor, because to me everyone in the world as long as they possible can should be exercising.

Geoff

Yeah, I think we actually agree there, where having large lean muscle tissue is one of the best markers for longevity. I think one, because you have large muscle mass it's actually one of the best is glucose syncs. You actually can pull down the sugar, and I think as you're saying it's actually one of the biggest drivers for maintaining insulin sensitivity. So, I think there is that trade off, okay you likely might want to limit activating MTOR all the time, but we don't want to do it to a point of having no muscle mass. That's not the trade off in terms of what you want. So what is that sweet spot? I think that's a little bit open to open science, and I think we're all figuring out what works broadly and then also what works specifically for each individual.

I think one thing that I think is interesting, and maybe this is again just more puzzling through your thinking rather than asking for a generic bite sized answer here. One of the big debates for what drives obesity is this calories in, calories out model which drives most of the rational behind obesity, or the carbohydrate insulin hypothesis. I saw that you've tweeted about that recently, I think there's good arguments for a little bit on why both are reasonable explanations or models here. I'm curious to get your thoughts about either frameworks and the pros and cons in your perspective.

Brad S.

Look, the first rule of thermodynamics, it's a law for a reason. It's not a theory, it's a law. So, and there is... I know some people argue against extrapolation to humans, but I dispute that, and I think everything in the literature to this point shows that. Heres what I would say, heres what I think the literature is quite clear because we have metabolic ward study so a lot of times, I know a lot of the keto proponents with the insulin hypothesis would site some... They basically cherry pick on studies that were done in free living populations, who can misreport data in terms of their energy intake data, their macronutrients data.

Not just the keto people, but the ones in the... Probably the misreporting I think would happen even more in the low fat group, because one of the benefits to keto, at least from everything we can read from the literature, is that there are properties within being on a ketogenic diet that do suppress hunger. Now, that in itself you could say, but that is consistent with calories in calories out... it's almost that people on the keto bandwagon want it, they have to have this... They're holding on to dear life to this insulin hypothesis, and I don't see why that's necessary personally.

I don't think it's supported in any way by the literature. We know that, by these metabolic ward studies where people are given food, and their energy levels are controlled their energy expenditure levels are controlled. There was a recent made analysis by a colleague of mine Doctor Kevin Hall, who's one of the premier researchers on the topic. There were 32 studies where the, and they only used studies where the food was provisionally provided by the researchers. So, basically they knew that the subjects were getting, they were eating what they were given. Basically they were not, they couldn't misreport if you will. Now, whether-

Geoff

They were in a ward, so people were monitoring all their food.

Brad S.

Correct, actually they showed a slightly greater, I don't necessarily buy this either, they showed a slightly greater fat loss from the low fat component. I think that is just statistical noise, personally. I don't see any reason why that would be from, but look so there are... And that's when protein levels are controlled. So, basically they're controlling, they're clamping protein and calories. It's very important with protein because it's not, when we talk calories in, calories out then people say, well then you're saying Skittles are the same as eating a steak. No, that doesn't say that because the thermodynamics, protein has a much higher... Multiple factors, but protein itself has a thermic effect of food.

Now, protein also has a satiating effect as the protein is, protein leveraging hypothesis as well, which causes you to want to eat more. So, there's a difference between saying a calorie is a calorie, and saying that basically all calories are created equal versus saying that energy balance is what drives weight gain, weight loss. That's pretty well established I don't think personally that, that is debatable. Within that I just want to mention, there are nuances that influence, like meats and non exercise activity you have to look at what the components are of energy intake, we know is the food that you're eating, but even then you have thermic effective food for different macronutrients. You have non exercise activity, thermogenesis, which is meat. There are things like gut health, which maybe might make certain foods less metabolizable than others. So, all of these factors are again can mitigate your energy balance. That's why it is a much more complex, some people want to then simplify it and use a straw man and that's not fair either.

Geoff

I think on the carbohydrate insulin hypothesis model, I don't think anyone is arguing you can eat 10 thousand calories of fat and-

Brad S.

There are people that do argue that.

Geoff

Okay, so I think that's where it's interesting where it's like, I think those people are a little bit too far on the straw man side of things. I think what you were referencing, if you eat three thousand calories of Skittles versus three thousand calories of a well formulated diet that is equivalent, that's probably too far on that side as well. I think the folks that are actually engaging and looking at the science are actually much closer, because I think as you were mentioning on a ketogenic diet beta hydroxy, beta rate is potentially showing the reduced grow in reduced appetites with that might drive a lower caloric intake. Then it's like, okay what drives what? I think there's actual discussion there.

It sounds like, I think the Kevin Hall study the one that I recall seems to be that the ketogenic, the lower carb group had a little bit higher metabolic expenditure, but it wasn't super sizable. So, I think the people on the low carb side of the story okay that's still something. The people on more of the other side of the story say, hey that's really low, the difference is negligible. I think, to me it's a little bit... I think it's a debate for a reason where it's not 100% clear. Otherwise, I think right-

Brad S.

You're mixing studies, so the study I was talking about was a systematic review, they did a made analysis of 32 studies that were done. Basically, a made analysis is where you pool the results of all the studies on a given topic, so they took every study that was done where food provision was given. They combined them into one very large study, the study you're talking about was a really interesting study that was carried out in metabolic ward.

Now, the issue there, so there was a brief spike in metabolism in the low carb group, the only issue was it went back to base line in 15 days. The total expenditure of calories during that spike was roughly a thousand calories, and it's at least theorized that was just due to gluconeogenesis where the body is shifting its use of... So, in the interim between where the body starts to utilize ketones, there is a period it's going to start to de-tabolize proteins particularly for glucose, both in neogenesis. That's an energy intensive process, at least my understand without that be my interpretation of why you saw this blip. But, that doesn't mean that it went back basically to base line in 15 days. So, that would not have kept up, or there's no reason to believe that it would've went back up again.

Geoff

Right, there was a spike then it just narrowed down where the difference was arguably something worth fighting for, or negligible. I think, depending on what side of the cup you're looking at, that's something that people can interpret as they see fit. Yeah, no I think that's right I haven't seen the meta analysis paper, which I'd be interested in taking a look to understand in that result. You mentioned the protein leverage theory, something I think is an interesting, has interesting explanatory power. Could you explain that to our audience?

Brad S.

Yeah, so simply stated the protein leverage hypothesis, it's really more of a hypothesis. Granted, a theory would be something, I guess it's kind of a weak theory, but depends on which way you go. But, it basically states that the body strives to take in a certain amount of protein, and when it's not getting sufficient protein you're going to have a drive to be hungrier and you'll start eating all sorts of foods. Generally just to try to make up and get yourself more protein, and the reason at least from a conceptional standpoint, it dates back to the caveman area.

If you start to not take in enough protein you're not going to have enough muscle to be strong enough to hunt, and to get away from your, people or animals that are chasing you. Be able to build your hut, or whatever it is that you have to do, work in the field. So, the body will then try to bring itself back to protein, to a certain homeostatic protein level by taking in more food. Thus, it's saying that if you're at protein, if you're eating enough protein you feel more satisfied and there's not this need to continue eating. So, you'll have less hunger and thus generally you're going to be less prone to gaining weight.

Geoff

Right, and then the extrapolation there is that the standard western diet, let's say an American diet, has a lot of processed carbohydrate fatty foods with low protein quality. So, you're just eating a bunch of this carb fat stuff, and because you're not getting enough of that protein you just eat more and more. Trying to cover that protein deficit, so if you eat a lot of protein that has leverage because your body senses that you have enough protein, you eat less of the carbohydrate and fat.

Brad S.

Yeah, that's correct. That's why, again I kind of think it's still more of a weak theory, I think there's something to it. But, I think to that as a fully explanatory mechanism is still sketchy, because the western diet has very highly palatable food. So, they actually I believe it was Kevin Hall's again, lab that just did this study, where they gave subjects ad libitum entrée to either very highly processed, highly palatable foods, or unprocessed foods. The people that were given access to the highly palatable foods, I think it was over the course of two weeks I forgot the, it was a cross over design of the same people. They ate an extra 500 calories a day, I don't know how much of that might have been due to protein leverage, or just because of the food being just very highly palatable as well.

Geoff

And was it the same macro nutrient ratio?

Brad S.

No, again my mind is a little blank at this point. I read over the study, but I forget I read so many studies. I've got to actually go back and reread, I somewhat skimmed it. But it was to me, just a very interesting study that I think shows that palatability of foods, when you have unlimited access as we do today to highly palatable foods, it drives... Like, when I'm eating a chocolate cake, or actually I don't like chocolate cake. A cheesecake, which is something I really like, I can pretty much polish off an entire cheesecake if I'm left to my... If I don't say, you know what I'm not going to be able to get of the couch next day if I keep doing this. So, I do have some will power, but if i didn't and there's people that are lacking in that realm, it makes you want to eat more. Where if I'm eating a salmon, I love salmon but I'm just not going to eat a pound of salmon. I can exert will power a lot more readily in that than I would with, let's say cheesecake or something.

Geoff

Yeah, and I think that's backed by physiological bio marker data, right? Where, proteins and lipids are more satiating than carbs. So, I think we all subjectively understand that you can probably eat a lot of candy or cake, and you probably can't eat that much steak, even though steak is great. I wanted to move on to the anabolic window discussion where, I think you were one of the first if not the first to popularize a concept around, hey the window of having to have that post workout protein is actually much wider than typically recommended in the bro science community. Where, I think a lot of people will say, you must have your protein shake 30 minutes after a workout, or you miss the anabolic window and you've totally ruined your post recovery protocol. Talk us through the research and how you've kind of blew a hole in that misconception.

Brad S.

Yeah, so I actually was a big proponent, when I say proponent I was a believer. I deferred to the authority figures who were preaching this at the time, and I actually have an entire chapter in one of my books where I expand on the importance of the anabolic window. So, you shouldn't say shame of me, I was naïve to that, the important thing is I took another look at this. A colleague of mine started raising questions about it, and I looked into the, I started really delving into the research and started saying, you know what it's really not what it seems to be. I first collaborated with a colleague of mine, who's a nutritionist in the field, first off if I'm honest to this concept when we collaborated on the paper 2013 I believe it was. In a real review of the literature, really that paper just the actual review, narrative review didn't seem to turn up much. We then went and I said, you know what to me this needs a meta analysis.

There's enough studies here, we can pool the data, which we did and again a pooling of the data really showed that it was not when you're eating, or at least a narrow window of when you're eating. It was the studies that were actually showing benefits were largely due to the fact they were giving a placebo, so they were given like sugar water instead of protein. So, the other group was taking in roughly point four grams more protein, so one point seven grams per day versus one point three. And, we do know through the literature it's pretty clear that roughly around one point six, one point seven is kind of lowered threshold for what you need to be in a metabolic environment. So, it's the total then, basically what we found from this made analysis is that its total daily protein that really draws anabolism. What I would say is that it's not that there is no anabolic window, so now people have kind of, again they straw man us and that's-

Geoff

Yeah, I was going to ask that for a nuance here.

Brad S.

-So, again it does come down to nuance. Number one, what I would say is that the studies do show, most of them show very slight benefits regardless. Even the ones that have controlled for protein intake, so if I'm talking about the average Joe or Jane that I'm coaching, would be coaching there's not going to be any difference. But, if you're a bodybuilder probably makes sense to take it in earlier rather than later. There's no downside to taking it in earlier. Number two, what we've started to glean through the literature is that it comes down to there's a window, but the window's more like a barn door. A barn door window. Where, it's a fairly wide window that should last probably five to six hours, well muscles are sensitized we know for 24 hours, I wouldn't want to wait until the 24 hour mark if I'm taking in protein because you're just losing out on a lot of that barn door, if you will.

But, if you're eating really what we've found is that you should think about the training workout as brackets around your meal. So, if you're having a pre workout meal the anabolic effects like I said are lasting roughly five hours or so, as long as you get your protein in there. If you're going to eat breakfast, lunch, dinner and let's say a late night protein shake or whatever. So, lets say you're having seven am, 12, five and 10. You're having meals around the clock, you'd be in you anabolic window no matter what, you wouldn't have to sweat at all. So, no matter when you're training within that block, you're going to be anabolic. So, it's not going to really affect you. Where it seems to have more relevance would be if you are training fast in the morning, or I would say if you're going to, if you're on an intermittent fasting schedule you'd probably want to structure where you're within, you probably shouldn't be training well outside of your intermittent fasting.

Geoff

Yeah, that makes a lot of sense. So, essentially the nut of it is that if you're not trying to get that percentage, which you would be if you're an elite athlete, or trying to win Mr. Olympia. Then it's really a barn door, just make sure you get enough calories to stay anabolic, don't be calorically restricted and you'll probably be fine. Which is probably helpful for a lot of folks looking to not freak out if they forgot their protein shake after their workout. It's okay, as long as you get enough protein in the next few hours you're going to be okay.

Brad S.

They don't need to bring that shake and slam that shake the second they're done, which you see a lot of times in the gym.

Geoff

Absolutely, one of the interesting papers that you worked on published recently was a fasted cardio study. So, I would say that a lot of our listeners probably are interested in doing fasted workouts, or fasted cardio for not for bodybuilding purposes, but more for blast out any remaining glycogen. Maybe some of the metabolic effects there, which we could talk about, and I think your study really showed that the fat loss difference was negligible at best, if there's any benefit. Can you unpack that study and tell us about your work there?

Brad S.

Yeah, so we had and that study is probably five years old now, so time flies. But, yeah we had basically I had, I think we went from a bodybuilding context or a fat loss context, where I'm older enough to remember the Bill Philips book, I don't know if you do called Body For Life. I think it's still the best selling fitness book of all time, or exercise book. But, Bill was a very innovative guy and he recommended that you do cardio fast, and his point I will power phrase was that if you did a HIT session, high intensity interval session, first thing in the morning fast that it creates greater fat loss than if you did an hour of steady state cardio later in the day after a meal.

It was something to that effect. When I started delving into that literature I started seeing a lot of holes in that, and I was a fan of Bill too when he advocated that it was the late 90's. There was very little literature on that, so he was basing it on works, a few studies that I think you could make that leap at that point, where the more recent stuff kind of dispelled that. But, it was really mostly acute studies where they would look at, they would just have someone do a acute bout and then look what their fat burning was. Their fat oxidation over the course of that bout, and hopefully we all know... Well, some people don't, that what you're burning during a workout does not necessarily reflect what you burn over a 24 hour period, versus a week period. It was really for looking at fat loss, it's not that you're burning in this limited time of training, it's what you're burning over time. I published a review paper I think around 2011, but there was very little studies on controlled studies on fat loss. So, there were a few studies that we longitudinal, but they didn't have a dietary component. So, we actually gave people a diet where they were following, they were on a fat loss diet, energy restricted diet.

Geoff

What was the macros like? Was it just the standard macro breakdown? Or did you have a keto arm?

Brad S.

It wasn't a keto diet, but it was a high protein, it was kind of probably more you'd consider it a 40, 30, 30. Kind of like a zone type of diet, but it was just a basically a basic diet that was somewhat high in protein. To make sure we, kind of protein I think at one point eight grams per kilogram if I remember. Again, its been a while since we've carried out that study, so I don't recall these specifics. But, it was around there. We had them do three days of cardio. One was steady state cardio, we didn't do hitt because the research showed that lipolysis is the breakdown of fatty acids from fat cells, so there is increased lipolysis. The thing is are we going to actually use that oxidize the fat for energy? That doesn't happen with the very high intensity cardio-

Geoff

It's an aerobic.

Brad S.

-You just have a lot more fat than you can actually oxidize, it ends up getting re-esterified, stored back in your fat cells. So, we did the steady state, which at least the literature shows has the potential for greater usage, from an oxidation standpoint. We gave one group a shake right before the training, we gave the other group the shake after the training, so that was a two to one carb ratio. So, I think 250 calories. Anyway, after the... So, one of them was training fast and the other, it was 10 subjects in each group. There were young women and really no differences, there was zero tangible differences in their fat loss or body comp at all. When you're now talking about health perspective, so from a fat standpoint, fat loss standpoint I just there's no evidence that it is beneficial in that respect.

When you're looking at it over the course of a longitudinal period of time, its body comp. From a, you're talking about metabolic effects as far as on health, that again is somewhat outside of my sphere of expertise. I've seen some of that research, some of the studies that I've seen acutely did show some benefits. Again, you've got to remember I might not know the other studies that have looked at it longitudinally, but you also have to remember that your body adapts over time. So, if you're doing an acute study you cannot necessarily extrapolate that, hey I have this acute study and we're showing greater insulin sensitivity. Well, is that going to continue over four weeks, six weeks, eight weeks, a year, two years, five years? In extrapolate that's, you cannot generalize that and that's why acute studies are good for generating hypothesis, but they're not indicative. You cannot infer long term results from that.

Geoff

I agree, how long was your study? Was it a two week-

Brad S.

Four week.

Geoff

-Four week study. Yeah, I think one of the interesting things that id love to see, I don't know if anyone's done this study, is I believe you get an acute increase in fat oxidation on the fasted population. But, as you were saying, but as you re feed you probably... Especially if you're re feeding on standard higher carb macro nutrient diet, you're probably sort of wiping out the increase in fat oxidation, or up working those pathways.

So, I could see, I'd be curious to see if you do fasted cardio then following on a ketogenic diet, which doubles down on the fat oxidation and fatty acid utilization, versus fasted cardio on a standard western diet. Versus a non fasted workout in a normal diet as a third arm. That would be interesting in terms of, just teasing out is there the up regulation of fat oxidation on a fasted cardio, does that carry over into diet? And therefore could you potentially see increased fat loss? I don't know if there are studies that have looked at that, but if there is that would be interesting to hear.

Brad S.

Some of the things you have to consider too, so when we're looking at fat oxidation where is the fat coming from? What depot? So, we know that intramuscular fat roughly 50% of exercise, and this has been shown readily over multiple studies. 50% of the fat that's oxidized from exercise if to intramuscular in untrained individuals. When people become more trained your body gets better at storing intramuscular triglycerides. That is not going to make tangible effects on your body, so if you're burying more intramuscular fat that's not necessarily better at least from a body fat standpoint.

That's number one, number two there is a thermic effect of exercise that seems to be blunted from being fasted. When are you then going to eat? So, there's so many other factors just looking at that narrow window within the time that you're exercising is very short sighted in my opinion. I'm not saying there may not be benefits from a health standpoint, and by the way can there be, we did more studies. You never look at one study to be all. Do another study, I did mention that the free living conditions, some of the food diaries I was getting did not look at some of the food diaries and say, hey this person is gaining a pound and they reported they were eating 12 hundred calories. So, you kind of throw your hands up and, without having a metabolic ward study, and I don't think anyone is funding that certainly for me for a group of collage age students. Now, maybe for health perspective you'd get that.

Geoff

Yeah, no I think you bring up a good argument there, which is that no one would recommend doing a fasted competition, right? You definitely fuel before a cycling race, or a football game, or a body... I don't know about bodybuilding, but for an actual workout, if you actually want to maintain peak performance you definitely want to be fueled. I think it's a good argument that if you're fueling you have a better workout, you actually increase the amount of exercise load that you do. Does that overcome the fasted nature of that workout?

Maybe, I think that's a good open question. I want to move onto just looking at bodybuilding as a sport, I mean obviously you've been in the game for decades. What has been the biggest shift in the sport from when you were up and coming as a young competitor in the sport, and now you coaching elite performers in the bodybuilding space? What has been the biggest changes? Is it much more delved in terms of quantitative bio marker tracking? Or, are people a lot more sophisticated around pharmacology? Of their inputs? Probably a little of that, I'm curious what is the most surprising thing that has changed over the years?

Brad S.

It's somewhat of an open ended question, would depend upon what segment of the population you're talking about. If you're talking about pro bodybuilders versus the natty bodybuilders, so I'd say certainly at the pro lever pharmacology is the primary thing since I was a product of the 90's with my bodybuilding. Bodybuilders that are there you look at their physique versus the physiques of today, and its just like dinosaurs against kitties. So, the pharmacology has gotten crazy and pro bodybuilding, now there's a at least a move to dial that away. The most recent Mr. Olympian winner at least was more astatic than going back at least a decade of Olympia's, and probably two decades at this point even.

But, I think that the biggest shift in an overall standpoint, in terms of your general bodybuilders, and I think this is a positive is that there is now more... And I think the internet is been a primary factor in this, there's been a shift towards taking a more evidence based approach. That bodybuilders are becoming more aware, many of them not just to follow the bros and that they will start now at least to give research more credence to some extent. I'm not saying that it's, there's still a ways to go. Like I also said earlier in the interview that there's something to be said that you can't just, it's not like research is the be all end all. You must take the experience of what we know through training itself too, into account because research is very limited into the bodybuilding segment.

So, I do think it's positive that there are now, there's more of an openness towards research in several pro bodybuilders. I consult with a guy name John Meadows frequently, we've done work, there's a pro bodybuilder one of the most astute guys I know. He's a really high level bodybuilder and is one of the most respected in the field, and he really puts his mind into the research and uses that to bridge the gap. As well as many others, I don't want to even start getting into names. There's a lot now I think more understanding of the importance of it, and willingness to utilize that and understand that a lot of the research now it's not just white lab coats, nerds.

Geoff

Absolutely. So, speaking of white coats and nerds, if you had infinite resources you were God of research, what studies would you like to see run? If you had infinite resources, infinite bodies to throw interventions at. What would you look at? What is peaking your interests right now?

Brad S.

Yeah, wouldn't that be nice. I mean one of the longterm studies using different periodization models that would manipulate variables in different ways. First of all, short term studies are good for what might happen in a given block, but how the things pan out over time is more relevant. Obviously with much larger sample sizes and carried out in a metabolic ward, where I can control everything and of course you'd want to have the subjects that you'd want.

So, you'd have to be able to pay them large sums of monies so that they will come and live in this metabolic ward, or this fitness camp whatever you wanted to do. So, I mean there's just so many studies that I'd like to do. But, I think the overriding point would be that they would be longer term, they would be well controlled, or better controlled like I said in metabolic wards, or fit camp whatever. Where you'd go to an island and just fly everyone to Honolulu and have a segment of that island corded off where you'd carry out the study, make all the meals, just have the training. Make sure you're controlling their energy intake and exertions. Just look at different parameters, different aspects, different training manipulations.

Geoff

Yeah, cool. Wrapping up here, what's exciting on your roadmap for 2019? How do our listeners follow your work? You're on twitter, you're on social channels. Let's do all the shout outs right here.

Brad S.

You can find me on twitter, Instagram I'm being a lot more active, Facebook I'm not quite as active as I was on Facebook just because the algorithms keep getting worse and worse. But, I'm on all those social media platforms, they can have different names on each one I think, but if you just put my name in you'll get me. I have a website called lookgreatnaked.com-

Geoff

Great domain.

Brad S.

-Where people can find me and I need to be posting more blog posts than I do. But, I like to put out a lot of free content and I certainly do podcast interviews and I generally announce them, and I will put this one on my social media too.

Geoff

Awesome. Thanks so much for taking that time to jump on, when you're next in San Francisco give us a holler, we'd love to host you out here.

Brad S.

Thanks for the offer, man.

Geoff

Alright, thanks so much.

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