Barbell Shrugged - Metabolic Adaptation w/ Dr. Eric Trexler, Doug Larson, Coach Travis Mash and Dr. Mike Lane #856

Episode Date: July 15, 2026

Dr. Eric Trexler returns to Barbell Shrugged to break down one of the most misunderstood subjects in fitness: how the body adapts to dieting, exercise, and energy restriction. Eric, a Duke University researcher with a PhD in Human Movement Science, joins Doug Larson, Dr. Mike Lane, and Coach Travis Mash to explain the constrained energy expenditure model, why cardio does not always produce the linear calorie burn people expect, and why the context of your diet matters. They cover metabolic adaptation, under-fueling in endurance and weight-class athletes, and why the body creates more friction as you get leaner or try to train hard on a fixed calorie budget. The crew also gets practical about fat-loss plateaus, "weight-loss resistance," diet breaks, refeeds, and reverse dieting. Eric explains why tracking errors often masquerade as metabolic problems, why getting extremely lean carries real performance and lifestyle tradeoffs, and why slower timelines are often the smarter move. He also shares what the research actually says about using refeeds and diet breaks to preserve metabolism and why aggressively beginning recovery after a hard diet may be more effective than dragging out a reverse diet. Whether you are cutting for a weight-class sport, chasing a physique goal, or simply trying to lose body fat without losing your mind, this episode will help you make better decisions with your nutrition and training. Links: Doug Larson on InstagramCoach Travis Mash on Instagram

Shrug family, Doug Larson here. And this week on Barb Bell Strug, we welcome back sports, scientist and physique athlete Dr. Eric Trexler to help us make sense the complex world of human metabolism, fat loss, and what it really takes to be lean and muscular at the same time. In this episode, he breaks down the science and real world application regarding ultra-low-calorie diets, refeas and reverse dieting, giving you clear guidance on exactly what to do when you're trying to get ultra-lean.

So if you're a person that's trying to lose body fat, make weight for a sport, or recover intelligently after an aggressive cut. This episode is for you. Enjoy the show. Welcome to Barbell Strug. I'm Doug Larson here with coach Travis Mash and Dr. Mike Lane. Dr. Eric Trexler back for a round two. You were on about two years ago.

We spoke on weightlifting and how it influences your metabolism. And we're going to be talking about a little bit of that today. But also we're going to talk about how your body changes and your metabolism changes and adapts to refeeds and other aspects of nutrition. But first, I know Mike Laney, you are close. You guys have just recently published a paper. You know, tell us your background. Tell us about the work you and Mike have been doing together,

and then we can move into other topics. Yeah, sure. So I've been, let's see, I did my PhD in human movement science at UNC Chapel Hill. Did a lot of research on metabolism and sports nutrition through the lens of exercise and physical activity. I've been bouncing around the fitness base for a while, did some powerlifting, did some bodybuilding, got back into the academic world in 2023, first as a postdoc at Duke University, and then a couple years after that,

joined the faculty here at Duke University, where I continue to basically try to learn more about health, wellness, exercise, and how we humans tend to regulate our metabolism. So that line of work has brought me into some strange places where simultaneously I'll be like emailing Mike about our paper about like muscle growth pretty strict like standard exercise science and then that evening I'm handling like squirrel blood or baboon feces to try to figure out how many calories they're burning at different periods in their life and different seasons. So it's been a really fun trip that now I find myself actually doing kind of an even balance of like human work and animal work related to the regulation of metabolism.

Right on. I figured you were 100% human performance. I hadn't realized you were doing animal work as well. No, man. We got squirrel cages in the Latin. We don't house our own animals. What we usually do is we collaborate with animal sanctuaries and zoos, for example. So I've been doing a lot of zoo work lately where they'll, you know, whatever species they're interested in, we'll try to figure out how many calories they burn, what kind of factors impact that. And it really helps, establish literature for, you know, better understanding how humans came to be the way we are because we do focus on mammals. But also helps practically zoos figure out the way to optimize how they feed some of these animals appropriately based on their energy needs. But yeah, our lab, going back to the time before I got there to what we do now, we've done work with elephants, mouse, lemurs, dolphins, and everything in between.

If it's a mammal, we've probably collected its blood, urine, or tried to get. essentially water out of its species. Wow. That is so good. Mike, you've been involved with that too with the animals? Mike, New Harris? I'm sorry, say that again. Somebody in a question was calling on.

Oh, got you got a phone call. No, I was saying, are you been involved with the animal research as well? Yep. So, be fair, I just deal with, you know, albino silverbacks a little bit and with a little bit of... Is this a dark test? Always. We're going to have to get some of the translation for Mike. And the other one being, it is fascinating because when you're looking at those animal models,

you know, obviously us chimpanzees, you got a lot more things in common. But, you know, hence why we see animal models, mouse models, and rodent models for a lot of, you know, pharmaceuticals. And actually, of all sides of Eric's research and kind of one side that I think is really interesting, and this is going from the constrained, you know, energy hypothesis, which you guys have been just proving over and over again, is the sheer size changes you see in internal organs like livers and kidneys whenever you put species in calorie deficits. And then obviously how that, you know, people like, I can't lose weight. And like, well, there is a certain amount your body resists you. And if you don't mind

kind of talking through one, that's resting metabolic demand and two, what you see with changes, both in the human and other animal models. Yeah. Yeah. So the constrained energy expenditure model, this is a really active line of research. Herman Ponser basically came up with the model about 10 or 11 years ago. We just published a review paper a year ago, kind of updating it. And literally, like, there's been three papers within the last month, very aggressively critiquing the model. And I'm still kind of digging into those to try to put together, you know,

kind of see which elements of those papers I agree with, any areas of contention I might have. But broadly speaking, the idea of the constrained energy expenditure model is that essentially it's the way I like to frame it is the exercise version of metabolic adaptation. So metabolic adaptation is simple. It's basically you start dieting and you start succeeding. You're in a calorie deficit. You're losing fat. You know, your body does have some number of adaptive levers it can pull to try to essentially downright.

regulate any kind of superfluous or less critical elements of energy expenditure. So it's kind of like when your phone battery drops below 20%, at least that's how mine works. It goes on low battery mode. So it stops checking all the background apps and it says, listen, if you need to call 911, I've got your back, but I'm not going to keep doing all the unnecessary stuff in the background because we need to make this battery last. So basically, energy expenditure adapts and it just adjusts downward a little bit. Basically, as a mechanism we believe to not totally prevent, but to slow the process of basically starving to death, right? Because your body doesn't know that you have a powerlifting meat or a bodybuilding show or a wedding or a photo shoot. Your body says, hey, not enough

calories coming in. We're going in the wrong direction. And as far as I can tell, you're slowly starving to death. And I'd prefer to step in and prevent that to the extent I can. So that's metabolic adaptation, the constrained energy expenditure model basically came about because in certain populations, Herman Ponzer, like I said, who I work with daily, he started to notice that energy expenditure didn't look as high as he thought it would be in some of these populations that do high levels of physical activity. So where he first started publishing papers in this was with the hodzah community. This is a group of hunter gatherers in Tanzania. And basically he was finding that, you know, all the predictive equations would suggest their expenditure should be much

higher than it, than the measurements he was getting with the gold standard measurement approach of doubly labeled water. And so it kind of started this process of figuring out, like, essentially, when people are on very fixed or limited calorie budgets and they start pushing their, their physical activity or their exercise higher and higher and higher, we don't tend to see this perfectly linear increase in physical activity at a certain point, When there becomes a big mismatch between the amount of physical activity you're doing and the very minimal calories that are coming in, what we tend to find is the same kind of deal with metabolic adaptation, this kind of down regulation, this partial attenuation as trying to save some of those extra calories from physical activity. Now, Mike, you alluded to this. The question is, where are we finding the savings?

And that's where there's a lot of debate. and I fear that in this space, some of the papers right now are talking past each other rather than working toward, you know, kind of refining the model. What I mean by that is sometimes people will say, for example, whether it's, you know, constrained model or metabolic adaptation, they'll say, well, there's nothing mysterious going on. It's just that your organs are getting way smaller and now your basal metabolic rate is lower. That's still an adaptation.

I don't know if that necessarily negates the idea of metabolic adaptation. It's just describing where the adaptation is occurring, for example. You know, another one is sometimes people will say, well, it's this, some part of this isn't physiological, it's behavioral. Basically, you've been doing a ton of physical activity and not adequately fueling that. So you, aside from the activity you have to do, you're becoming more sedentary in the other hours of the day. So, you know, some people argue very, you know, enthusiastically that we should be focused

focusing more on the behavioral adaptations to this energy mismatch more so than the physiological. So there's all these kind of arguments that are going on and people finding creative ways to quantify these different things and saying, well, it looks a certain way when you quantify it that way, but it looks different when you quantify it another way. So there's a lot of mathematics battles going on right now, not battles. I think everybody's in it for the right reasons, which is to figure out how this machine works that we all inherited, that we call a body, still trying to just figure out what's going on here. But certainly there seems to be a high level of agreement that, for example, if you decided today, Mike Lane, that you wanted to be a very slim

version of yourself. And so you are going to basically keep eating the way that you're eating, or just really not think much about your diet at all. Just kind of say whatever, I'll keep doing my thing. And I'm just going to do a tremendous amount of cardio to induce a tremendous amount of weight loss. Time and time again, we find in randomized controlled trials that people lose sometimes only 30 to 50 percent of the weight that we would predict based on the equations that we have available, meaning something is happening, whether you want to attribute most of it to behavioral changes or physiological changes, changes in organ mass, changes in basal activities, like for example, maintaining lower levels of sex hormones and thyroid hormone, maintaining a

slightly lower body temperature. You know, perhaps there are changes in movement efficiency, the actual energy cost of movement. There's been a lot of a lot of proposed mechanisms about where these adaptations can occur. A quick break in the action here to let you know that I've just recently chosen to get back into coaching. And I specifically am looking to coach Masters jujitsu athletes just like myself. I've been doing jujitsu for 22 years and strength and conditioning for 30 years. I'm a black belt, of course.

and I live that life. I understand exactly what goes into it. I understand what's like to run a family, do Jiu-Jitsu, try to tie strength and conditioning into it all and all of the ups and downs that come with it from joint pain to busy schedules to travel and all the things. So if you are a master's jiu-jitsu athlete and you're looking for some support, I'm happy to give it. You can DM me on Instagram at Douglas E. Larson or you can email me, Doug at barbell shrug.com. Happy to help. Back to the show. a lot of proposed mechanisms about where these adaptations can occur.

And what's really fascinating and what's fascinating and really frustrating is that some of these changes are small and it's hard to measure them with an extremely high level of precision. So, for example, there's just a paper a year-ish ago that came out of Tel Aviv University. and they did this very comprehensive study where they measured like every individual element of, you know, these adaptations you could think, including in an animal model, they looked at, actually they looked at organ size in humans and animals. And what they found was really annoying. They did a great job on the study, but what they found was it did look like there was some compensation that happened, some calories that should have been burned seemed to be

getting conserved. But when they measured all the individual parameters, all the individual element, because there's some measurement error associated with each one, they couldn't really look at the smoking gun and say, here's where the calories went. They just said the calories went somewhere, and it could have been some combination of these different areas. Could have been reductions in organ size, reductions in other basal processes. Like I said, we have this whole kind of neuroendocrine slowdown, and you can argue the caloric

cost of that. But, I mean, we've probably seen this with all sorts of athletes. when an athlete comes in and says, I've been training my ass off and not eating enough, we already know what the blood panel's going to look like. It's going to look like low thyroid hormone from the top down, Tsh, T3, T4, all of the above. We're going to see lower, you know, sex hormones, whether it's testosterone and males, estrogen, and female.

So we already know what this whole neuroendocrine kind of cascade looks like. So, yeah, there's all these different, all these different nuanced ways we can try to look at where these calories went and it leads to a lot of arguments. But the practical takeaway, I think has broad agreement, which is that when you do try to lose weight, there are some of these adaptive changes that occur. And that ultimately makes the process a little bit tougher. And the same thing goes, I frame that as when you're trying to lose weight, but the same thing goes, if you're just an endurance athlete who wants to do a whole lot of training and isn't eating enough to fuel all that training, well, you're still going to find yourself in a sizable

energy deficit. And to a certain extent, there's going to be ramifications of that when it comes to your bioenergetics. And why would an energy athlete not want to fuel? I mean, like, you know, that's a great question. That would make no sense. Exactly. Yeah. So there's basically two common places where we see athletes under fueling relative to their training volume. Number one is just really bad advice and kind of social pressure, for example, I'm going to speak in generalizations and kind of stereotypes here, but you're a female endurance athlete and your coach has decided that you need to be five pounds less because, you know, we think you're going to have better running economy if you lose five or 10 pounds. And so you're you're restricting your calories to lose weight

and you're still going to the team practices and putting in all the mileage. That's one place where we see it again that's just a really short-sighted bad advice coming from coach i i hope that we see less of that than we used to but another place we see it is some people that are trying to be really elite at some really crazy things um it becomes really difficult to fuel so for example when we look at people who are doing really extreme ultra endurance events or really pushing you know to be the best marathon or on the planet. It's not unusual for us to see instances where, you know, the way that we like to frame energy intake for those folks who are really pushing it is we look at their total calorie expenditure or their total calorie intake basically divided by their basal metabolic rate. So as a multiple

of their basal metabolic rate. So we call that metabolic scope. And what we tend to find in several studies is if you look at a person's metabolic scope, basically how many calories they can burn as a multiple of their BMR over short timescales, people can burn basically as many calories as they want. If they hate themselves enough to push their metabolic scope to six for a couple days, they can absolutely do that. There's no question. But so, and that's insane, right?

But we're talking about something that's occurring over timescales of like days or hours or days, right? But when we look over the long term and we say, we're going to watch you and actually measure you over a 365 day period, we find that the maximal like sustainable metabolic scope tends to be about 2.5 times basal metabolic rate. And that's been found multiple times from multiple research groups in totally different cohorts. And it seems to be kind of continuing to triangulate at about that number. We don't believe, or I'll speak for myself, I don't believe that that is a like law of physics or physiology that that is a true human ceiling, I think the best explanation for now is that seems to be the highest number of calories that people can reliably convince themselves

to eat. And so, like, to answer the question of why would there be this deficit in these high-level endurance athletes is because they're pushing their training volume to an extent that they physically can't get the calories in? And either because they don't have time or because they literally feel sick when they try to eat, you know, three times their basal metabolic rating calories. Yeah. That would be difficult. To contextualize what Eric just said in more freedom units is you would have, it would be a brutally

hard workout to burn about 0.5 of your wrestling metabolic rate in an hour. Like that would be a painful hour. Yeah. And like for most people like zone two, zone three, they're probably getting through maybe like a quarter. So when he says 6x, you're talking about 12 hours of just getting pile driven. So like, yeah, that is like a, wait, keep going down the numbers path. Throw more real numbers behind this.

Like, Bisma metabolic rate, how many calories is that on average for what size a person? And then what does an hour training look like? Like throw all the calorie numbers out though so we can have. So you think about, you know, a guy my size, you know, 215, 10 on a very good day. I'm probably arresting calorie burn of a little over 2,000 calories. And then if you figure I'm going to have to burn over 1,000 calories in an hour, that is me on an assault bike going hard, like RP8 for an hour. And I'm somehow going to keep that up for essentially six hours,

sorry not six hours, but if I go through a 0.5 and I'm trying to go up to that six number, like that's insane. Like that's just brutal. And to contextualize that, like it's worth, I don't know if it's worth remembering. It's worth noting. I find this very insulting to my senses when I think about it. But there are endurance events where literally the event takes days.

You know, they say, here's the starting line. We'll see you at the finish line. It will probably be in six days. And the contestants say, are we supposed to sleep? And they say, it's up to you. Do whatever you want. It's this many hundred miles. Just get to the end in as short a time as it possibly.

take. So when you're wondering, like, but how could you possibly accumulate that type of metabolic scope over these short time scales? You got to remember, there's events where people will literally just exercise for 36 hours, right? And there's, there's events there. There's, uh, Herman, before I got into the lab years ago, actually did a study with a race across the USA where people literally averaged a marathon a day, six days a week for, I think seven weeks straight. I mean, it was, they literally ran from the beach in California to Washington, D.C. And it was by doing a marathon six days and then taken one day off on average. So, yeah, when you think about like, how does that MetaBlock scope happen?

It's like, well, if you're doing daily marathons or if you're doing running events that last 12 hours a day and you're doing that day after day, like, it can happen. But I also like with Eric's piece is it's keeping it relative to the individual. because those people that are doing the run across America, I doubt there's many Clydesdale class survivors. And if you are, email me, I want to talk to you because you fascinate me. But a lot of those folks that get into those type of long distance events, you're talking about 140-pound body like that still requires a lot of calories,

but nowhere near as many calories as a 200 and some odd pound individual. So hence why the metabolic ceiling thing is useful because it's not thinking, It's the old school, 35 grams of protein is all you need in the sitting. I'm like, yeah, if I'm a hundred pound person, it's probably accurate. But if you're half-worthorsin, this is how we lose your muscle mass. Quickly. So for the majority of our audience is not ultra-altra, ultra-endurance runners. If they're on reduced calories, it's because they're either just trying to generally lose body fat

or they're in a weight class sport. They're weightlifters, power lifters, jiu-jitsu competitors, MMA fighters, et cetera. So for those people that are just trying to compete in a weight-class sport, What are like kind of the similarities and differences between everything we just said? Yeah. So this is actually, this comes back to one of the things that's really important about this constrained model is I mentioned Ponsor came up with it over 10 years ago and we just wrote a review paper about it last year.

And believe it or not, as scientists, the review paper wasn't, hey, everyone just wanted to remind you, we were perfect 10 years ago and we're still perfect today. You know, so the model has been updated. It's been adjusted because a lot of research has been done in those 10 years. And one of the most, I think there's kind of two important takeaways from our kind of update to the model or to the discussion of the model. Number one is that it seems to take time to actually like occur, this kind of downward adjustment of metabolism. So we tend to find that in the studies where they said, here, here's this dose of cardio, go do it and we'll see how your metabolism adjuster changes.

It seemed like it did take months to start to see real kind of downward adjustment in the cases where it was observed. The other thing, which I think is much more critical, is whether you are in a calorie deficit or a surplus, or, you know, I would say whether you're in neutral to positive energy balance versus negative energy balance seems to have a huge impact on whether or not this constraint or downward adjustment of metabolism actually happens. And so that's why it doesn't really matter that a lot of the folks listening to this do not want to actually run from California to Washington, D.C. continuously. Who would? Right. No. But what's important is there have been a few

studies that actually try to say like, are we sure this constrained model even makes sense? Should we, let's test and see whether or not the constraint model seems to work better or what they call the additive model, which is kind of the default assumption, which is the more exercise you do, the more your total energy expenditure goes up and it's essentially perfectly linear. What they tend to find is with more realistic doses of exercise, the type of stuff we would engage in, the additive model actually is better when people are in neutral or positive energy balance. So if you are adequately fueling your exercise and you add some exercise, it looks like your body burns approximately the amount of calories we would think. The real distinction comes in those two areas

I talked about. Number one, you're doing so much exercise. You literally can't fuel it. And so you're in a deficit by default. Or number two, you're trying to lose weight or you're on a fixed calorie budget and therefore you're under fueling relative to this new exercise that you've added. So I would say if you are, let's say you are just someone who lifts for fun, you like to be strong and muscular. That makes sense. I get that. And you're like, you know what? I want to add some exercise just to kind of keep my ticker in check, you know, keep my heart and cardiovascular system healthy. And you're not on a diet. You're not trying to lose weight. You're eating plenty of calories. Yeah, you're going to burn basically the amount of calories that we would predict from that cardio.

But let's say you're the power lifter who says, I think I could really make a splash if I go down two weight classes. So I'm going to do a nice long, you know, steady weight loss, you know, I'm going to lose 20 pounds, 25 pounds, whatever, over a case of many months, you will do due to both the metabolic adaptation of, you know, reducing your calorie intake and if you're using cardio, we can kind of lump it all together and say, if you sit down on day one of this endeavor and you say, okay, I'm going to increase my cardio this much and reduce my calories this much, draw the line. Okay, I'm going to meet my goal on that date. If you don't make further changes along the way, it's not going to happen. If you're expecting this to be some

linear process, your body is very likely to adapt and kind of have a little bit of extra friction along the way. And as a result of that, you're going to have to view it as more of a kind of incremental process or kind of you go until you start to plateau and then you have to make another adjustment, drop the calories more, increase the cardio a little more. So I think the main takeaway for that type of audience is that the actual energy cost of just adding a bunch of cardio to your day, the net energy cost after everything shakes out metabolically and any kind of potential compensations occur, the context really matters. And the biggest contextual factor, in my opinion, is are you in neutral to positive energy balance or are you in negative energy balance? And so,

Like, I mentioned that there's a lot of arguments happening right now about whether or not the constraint model is quote unquote correct. And to be fair, it doesn't have my name on it. So if somebody like flatly debunks it, like, what do I care? I'm not going to lose any sleep. But I will say this. I don't think it makes sense to frame the conversation that way. So I've seen some papers come out that say, we found in our sample that the additive model was better,

therefore the constrained model is unsupported. I think a better question we should be asking so that we are working toward a resolution rather than talking past each other in these papers is let's try to elucidate the scenarios where the constrained model seems to be better. So it's really like I've seen so many papers where people say, look, there was a linear relationship, people who exercise more, burn more calories. And I say, okay, the crazy people at the high end, what was their maximal metabolic scope? and they tell me, well, it just so happened to be exactly 2.5.

And I'm like, okay, that doesn't really disagree at all with any of the stuff we've been saying about this. If you told me that you had someone who was maintaining a metabolic scope of four and they'd been doing it for the last three years straight with good measurements, then I'd say, hey, we have a problem here. We need to figure out why our model is so, has no room for that type of reality. Same thing goes. I have people who say, hey, the more exercise people did, the more calories they burn and it was linear, then you look at it and it was a very modest amount of exercise and nobody lost any weight in the trial. So everyone was a neutral energy balance and they were doing modest amounts of activity.

And again, it's not is the constrained model right or wrong. It's where does it apply? And I would say where it applies is you're doing so much exercise that you literally can't fuel it or you're doing exercise and you are intentionally. under fueling it. So the context is really big. Yeah, earlier you were saying that it's not a linear process. You're going to have to make adjustments along the way. So say you're that person, you're in a caloric deficit and every two weeks you bump it down by 250 calories. And there's only so many two week blocks that you can go through before you're getting into so called like

dangerously low calories or just out of calories altogether. So say you're taking in, say you're actually, you're actually measuring correctly. You're actually like you're taking in the amount of calories you think you're taking in and you're not just wrong. You're taking in 1,250 calories and you're actually not losing body fat and you're you plateaued, so to speak. Like, where do, you know, where do refeeds come in? When, when do you stop and just go, you know what, I'm not doing this anymore? Like, I'm going to put some muscle back on or change directions. Like, how do you handle like a real plateau? Yeah. So I do want to make a distinction. Plateaus are extremely real. And in fact, they are what we would predict, you know,

depending on how quickly you're going, right? But the plateaus, we expect that to be the case. I just gave a talk this summer in Australia where I was talking about basically why it was four fitness professionals. It was why so many of your clients think that they are weight loss resistant. Basically, everyone thinks they're this like, not everyone. There's a huge percentage of people that think they are in this top one percentile of metabolic anomalies.

And the math can't, you can't have 30 percent of. of people in the top one percentile. It's not how it were, or bottom one percentile, however you want to frame it. Eric, all of our children are above average. Correct. Yes. I know that. But, but, but no, so basically, I looked at the math and I said, we've got this not correct. We've got this great data where they got a gold standard total daily energy expenditure data from 9,000 people ranging in age from like a few weeks old to 96 years old, from all corners of the country, hunter gatherers, people that sit behind a desk and work in corporate, like, you name it. We have the human population pretty much covered in this data set.

And basically what I said was, if this is true, if there's this massive number of people who have these anomalously low energy expenditures such that they truly are resistant to weight loss, and despite the fact that they're 271 pounds, they're not losing weight at 1,250 calories a day, it should show up exactly here in this chart. and there was nothing in that area of the chart. It just hasn't been observed, and we've looked and looked and looked. So that's the one thing is so far in my career, 10 times out of 10, all the anomalies, we start digging in and we find out, oh, your kid has chicken nuggets when dinner was

actually salmon and you eat four chicken nuggets. Right. And that's where we find. And we start going through and we're saying, oh, you don't track vegetables, but they do have calories. You don't track sauces and condiments. They do have calories. I've literally sat down with a client where Doug, like you're saying, I said, listen, it's not that I think the calorie target in your plan is dangerous.

It's that I don't want any person on the internet to know that I assign this to an adult man that's your size. Like, this is purely a reputational harm thing. And so I want to sit with you and actually spend an hour talking through your day. And we found 700 calories within the first 15 minutes of the call. Like we can just go track. Give me an example. Like what? Like what?

So this actually was one of the guys who basically, the things I just said, check, check, check. So he had young kids and like I hate food waste. I'm with him. But basically he was eating three quarters of a child's entree for dinner every night. He's great. Like chicken nuggets and macaroni and cheese just so it doesn't get thrown out. And then it was again, not tracking vegetables, not tracking sauces, not tracking condiments. Oh my God.

So you start to find, you know. And so basically his calorie plan went from. 1,200 calories a day to like 1750, you know, in the blink of an eye, which would put them right in the range that we would anticipate. But so I did want to lay that out and say that, you know, there's research where it's not that unusual for someone to basically report their calorie intake is 50%, 60% of what they truly are taking in. Like there's been studies where they found people who self-reported being weight loss

resistant and they'll be like yeah I ate like 1,200 calories today. Then they go like actually walk through it with them. It's 2,800 calories, right? Like I've had massive, massive differences. So but again, getting back to your question, the plateaus do happen. And let's say you are doing everything, right? What should a person do? This is where I think my views actually get a little bit I wouldn't, I wouldn't say controversial because no one cares about me enough to generate controversy around my opinions. But I disagree with a lot of folks on this. And that is my threshold for what becomes a dangerous level of calorie intake makes a lot of people uncomfortable. But the reality is if you get out of like the fitness mind hive kind of collective brain where we all decided

apparently arbitrarily a long time ago, a female can never go under 1,200 calories and a male can never go under 15 or 1,600 calories, if you break out of that and look at the the weight loss literature, you find that the most common weight loss intervention known in the medical literature is we're going to take a bunch of people who weigh like 240, 280, 320 pounds, and we're going to give them three shakes a day and they're going to eat 900, 10,000, 1,100 calories a day. We're just going to give them three shakes a day, 1100 total calories and say, check back in in 24 weeks when the study's over.

So the idea that, you know, you have like a bikini competitor who's 110 pounds and it's like, whoa, you can't put her under 1,200 calories. You have to, in a lot of cases. So my take on this is if it's good enough for someone who weighs 280 pounds in a medical weight loss study to be on an 800 calorie diet for 20 weeks, I actually do think that sometimes you sit down with someone. Once you've ruled out all the stuff I talked about, you say, okay, it looks like you really are struggling to lose weight at, let's say, 1,600 calories for, you know,

an adult male, I would say, okay, well, the math is what it is, the physics is what it is. We're going to have to go down if you want to actually kind of hit this target that you're talking about. The question is, and I don't say this is like some kind of like, you know, motivational hype up speech, but in a very literal way, exactly how badly do you want this? And I always said, I don't frame it that way because it almost seems like a challenge. But I really do sit down with someone. I say, so you told me that you want to get down to 6% body fat.

You also have two young kids in the house and a wife and a job. And when we do the things that's going to take to get you there on the timeline that you quoted, your job performance may suffer. You may be more irritable. You may find that your lethargy is actually impacting your ability to do the things that you call being a good father. And so I do want you to actually really get interested. perspective here and figure out how much better is your life at 10% body fat versus the 6% you

were aiming for? And how do you want to weigh these different tradeoffs? And usually what that, what that ends up looking like is we decide one of two things. Number one, this ain't for me. And I prefer to adjust the goal a little bit. Or number two, I do want to get there. But the number you just told me in terms of a calorie target scares the hell out of me. So what if instead of getting there in two months, we say, let's try to get there in. six months. And we just go at a glacial pace. And usually one of those two is where we end up finding success. I mean, I feel like that's where a lot of coaches go wrong. It's not, not having this deeper conversations and like really trying to break things down, trying to do

the exploration of like what's really happening. What do you really want? Like if you got a family, like extreme weight loss is probably not a great idea if you want to stay married. So, And to further go, I think it's always important that we have, we understand our underlying assumptions. Because one of the things people are like, well, that's not healthy. I'm like, yes, being on a bodybuilding show and being someone who wins, that is not a healthy person. No. In that moment, they are so incredibly lean. The flu is incredibly dangerous at that point because they have so little reserves to draw from.

And so it's one of those things like, yeah, don't be wrong. I respect you one that steps on the stage, and I'm not saying like, you're unhealthy because you're doing it. And I haven't talked about the substances people will use to get to almost stages in other contexts. But if you want to look that way,

there's a reason most people don't. Right. Because it is truly physiologically challenging for the vast majority of the population to get into that type of condition. And so hence, like, yeah, if you, this is the cost of doing business. You know, starvation is, 100% effective for weight loss. It's not sustainable and it's not healthy.

So I really just want to start a fight with Eric just for fun just because, you know, I like to punch up, not down. I want to see you to go out and have the office. I got height on them. That's my one advantage. Oh, for sure. Not wit. Yeah.

No. So here's what I would say, though, about the idea of, is this healthy? And I'm not, I'm not disagreeing, but I do think it's worth. adding like one little layer of, I mean, Mike, we're professional academics. What would we have, if not pedantic quibbling over details? That's really the whole business. So here's what I'll say is when you talk about something being healthy, you have to kind of say, well, what is health? You know, how do we define that? Because we can look back at like how long did bodybuilders live relative to their peers before drugs entered the picture? And the answer is that they had,

it was not deleterious to their lifespan by any means, right? It was actually increased their lifespan compared to the regular population. Yeah. So in terms of if we're measuring health by this is going to shorten your life, that doesn't seem to be the case unless you're taking all the stuff that makes your heart four times as big and all your organs four times as big and the whole deal. And I mean, let's be honest, a lot of the stuff in bodybuilding is there's been a lot in the last several years, acute deaths from, you know, diuretic use, insulin use, things like that. So, but that stuff's off the table for this conversation. So then the question is, well, is it healthy to be on these ultra low calorie diets? You could make an interesting argument getting way out of the fitness space and going into the

pure biology realm that the healthiest thing you can do is extreme calorie restriction. It seems to be the only intervention that across multiple species reliably increases lifespan, huge caveat. It doesn't necessarily mean it's the most enjoyable way to live life because we're talking, in very low calories forever. Most people when you actually crunch the numbers say that longevity benefit is not worth it to me. And you have to remember these lifespan advantages are occurring in laboratory conditions.

And in laboratory conditions, you're not necessarily scared about like, what if I am exposed to a huge pathogen load and need my immune system to mount this robust defense? Like Mike, like you were talking about, what's really fascinating, John Spee. Eakman wrote a really cool paper about what he calls, I think the empty cupboards hypothesis or something along with something to do with cupboards being empty. But the idea is calorie restriction does have a lot of benefits that extend lifespan across many different species. But there are also these critical things where it's like, but if that happens, you're

totally screwed once you reach a point of restriction where it's like, listen, if you get a cut and you need to hope that your immune system can prevent that from becoming a lethal infection, then it doesn't really serve you well to be 6% body fat and on 1,000 calories a day. So I just say that to kind of remind folks of a broader kind of view of when we say something is unhealthy, usually in the fitness space, what we're talking about is that is psychologically not healthy. And it's going to cause a lot of preoccupation with food, a lot of. a preoccupation with body image. It's going to make your overall quality of life way worse. So we have to always contextualize, you know, is this, if you're a bodybuilder, I've done this

myself. I went in. I was a few weeks out from a competition. I got my blood panel drawn, and it's all red. If they print out the sheet in color, everything's outside of the reference range. Is that healthy? Well, I didn't plan to live the rest of my life like that. I can tell you, I was clinically hypogynadal, clinically low thyroid. All of that went back to normal within a couple months. It's not like it rendered me infertile or, you know, perpetually hypothyroid. And so then the question, I live to tell the tale. I didn't catch a flu and die from it.

And we don't see that happening with a lot of natural bodybuilders. So the isn't healthy thing, again, is just such a loaded question where you have to say, like, you know, Travis, you mentioned sitting down with an athlete and talking about the pros. and cons, you know, the cost of benefit of do we really want to do this. The same thing. If someone sits down with me and says, is it healthy for me to actually do this? I'll have to say, well, how do you define health? Is it every time you go to the doctor, your blood is within reference ranges across the board? If so, no, this is not healthy. If you're talking with a female athlete who is, you know, currently humanoreic and they're saying, what am I getting into here. If they define losing a regular menstrual cycle as as unhealthy, then no, this may not be

healthy. We see that a lot of times in weight restricted sports or, you know, really high volume endurance sports. So, yeah, health, just like goals, just like that cost benefit, we have to be really specific to the individual and say, how do you define health and how do you want this to go? But chronically, it's probably not a bad thing. You know, you're talking about an acute health. Exactly. Yeah. Yeah. And so, yeah, when, and that's, the thing that I think the whole reason I forced us into this tangent is a lot of times you'll see just this broad sweeping statement. I'm a guy. And when I get down into contest shapes, sometimes I do for brief periods of time. I tiptoe below 1,500 calories a day. And so I'll see all

this stuff on the internet. That's not healthy. And then I'll say, what do you mean? And it's not the rhetorical question is how are you defining health and over what time scale? Because I don't have any belief that me being at 1,500 calories a day in 2017 has had any lasting impact on my health. So yeah, it's about how you define it and over what time scale. And just two other pieces. One, the flu is a bad analogy. Thank you for cleaning that up with me, Eric. And the thing for everybody listening is pretty much the inverse, as far as the current caloric surplus, it's similar. The harder you're pushing that body weight upwards,

the more likely you're going to see to lead to various things with perhaps your lipid panels and otherwise. But the reality is, it seems to be the slower you go, the more sustainable it is, regardless whether we're talking about weight loss or weight gain. Oh, again. Yeah.

So what, what the reality of a Zoom call here, we're all talking over yourself? Well, what's the best way to come out of a deficit like that? Your labs are all in the red. You're out of the, you know, the reference ranges.

and a couple months later, you're back to normal, so to speak. Like, there's probably better and worse ways to dig yourself out of that hole. What methods or tactics did you employ? And kind of what's the best way to go about that? That's a great question. This is something I've written about a lot. Back in probably 2013, 2014, people started talking a lot about reverse dieting, this idea of, you know, we talked about how you're going to hit plateaus.

So you have this kind of incremental. slow process on the way down on a diet. And people said, well, hey, what if we reverse that on the way up and take a nice slow incremental process, just slowly reintroducing calories? Maybe we can fully recover from this diet and work our way back up to a very comfortable calorie intake. And this was being framed mostly for like people that are getting really shredded, you know, bodybuilding, physique athletes, et cetera.

And I would discourage people actually from taking that approach. You can find the receipts of me in 2013, 2014, speculating that that might be a good idea, but I've participated in some research studies getting to the bottom of that, and it just doesn't seem to be a very advisable approach. What you want to do is get your body back to a place where it can realistically kind of kickstart recovery. So we've done studies where we look at physique athletes and say some of them are going to go a little bit quicker in their recovery, reintroducing more calories, regaining more

weight a little more quickly. Some people are going to go very slow. Add five carbs at a time week over week and just at a snail's pace start to rebound. And basically the people that kind of just say let's rip the Band-Aid off and start recovering, they do quite well. The big caveat is there is a point where that no longer actually serves you where it becomes counterproductive. So I'm not saying do the thing everybody did in the late 90s where it's like an early 2000s where it's like the day after a show you've regained 18 pounds. That's not good. But what we want to do is, you know, very quickly say, you know, if you were at the end

of your diet, like for me, if I'm down at 1,500, 1,500 calories, there is no reason for me to be hanging out below 2,000 calories for a long time. I should immediately jump up to 2,000, 2,200, you know, really start that process, get moving in the right direction. But once you make that initial jump and you start to see weight slowly progressing in the right direction, just kind of steer the ship that way, just kind of. to ease your way back to what you consider kind of a sustainable longer term weight. But yeah, you don't want to just drag it out forever because what we tend to find is those

folks who drag it out forever, their resting metabolic rate stays suppressed. Their thyroid hormones, their sex hormones stay suppressed. Restoring a regular menstrual cycle takes longer. You're just delaying the inevitable. And what's really cool is there's a study called the Minnesota Starvation Study. where conscientious objectors instead of getting drafted into combat roles, essentially were voluntled to do a study instead where they starved them. It was they had to live on a military base.

Every morsel of food was given to them by the study staff. And they got down to a group average body fat of around 5 or 6% using the measurement technologies at the time. But you can look at the images. It's jarring. They looked deeply unwell physiologically. They were skin and bones. It's really, you can find the pictures of them. But basically...

These were not bodybuilders. They were normal people. Yeah, normal people. These are adult men who, by the end of the study, were like 115, 120 pounds. I mean, they looked awful. But as part of the recovery phase, you know, the U.S. government and the researchers, They wanted to figure out with all the famine happening in Europe, how do we actually safely get someone back to a healthy body weight? And the first 12 weeks after the diet phase, they had them basically start re-feeding at four different rates.

You know, one group went really fast. One group went really slow. The other two groups are in between. And what was interesting was they did that for 12 weeks. Obviously, the weight gain differed a lot from group to group. But then they checked in after like, I think it was another 12 weeks or so or maybe 24 weeks of just, okay, do whatever you want. And basically everybody ended up back at the same place anyway. And so a lot of these folks that are delaying their recovery with these reverse diets, they feel miserable the

whole time. It's extremely difficult to do. They're delaying their ability to get back into a more productive place hormonally physiologically. And so far the best data suggests they're probably just delaying the inevitable and they're probably going to end up in the same place as everybody else. So it's kind of a lose-lose situation. Yeah. It was good to hear. I used to make some big cuts when I was fighting MMA between like 2006 and 2012 and again I've said this on the show many times but I would I would lift I would do weight lifting at 94 kilo 7 and then I'd go fight welterweight at 170 and I kind of bounce back and forth so I had these big weight swings and to your point many times in order to hit that weight I was at very low calories and because

it wasn't about health it wasn't about body fat percentage it was just about weighing in at the weight on the day and that's the only thing that mattered and so there was a lot of times where I just wasn't eating because I just I got three days left and I got to just hit that number but coming out of it, you know, I go down and then coming out of it, I just went back to best practices, so to speak. Like, I just went back to eating the highest quality food I could find with a good macro split and four to six meals a day. And I wasn't really counting calories at that point.

I was trying to hit my protein goals, trying to hit my fiber goals. But I was just eating when I was hungry. I wasn't stuffing myself. I just went back to just like the first principles of nutrition. And it all seemed to shake out just fine. Yeah, yeah, and I've been there as well. I wrestled back in the day. And yeah, I mean, it was basically you want to get back to something that looks like a healthy, sustainable diet, and you don't want to delay that.

You know, you want to get moving and get your body nourished because, you know, again, we talked about, you know, am I healthy at the end of that diet? I don't know. Am I fully nourished? No. I mean, like, that's the reality. When you're eating 14,500 calories a day and train and hard, you definitely want to make that initial jump. And then, like you said, get to those best practices with nutrition. I am recalling. I know we're, we're, we're, uh, running up on time here, but many minutes ago, you asked me a question leading me into talking a little bit about refeeds and diet breaks and things like that. And I do want to at least address from a practical perspective, a lot of folks have framed those. Again, hand up. I was kind of optimistic about these. People can find the receipts back in 2013, 2014, and so on. But the idea is what if we can kind of, I'm going to use like very informal language,

but what if we can kind of trick our body on the way down? Like we talked about all these adaptive processes that slow our metabolic rate because we're being so restrictive because calories are low. What if we interject with a couple high calorie days here and there, maybe a higher calorie week here and there and try to convince your body, hey, we're not starving. we're just going through these intermittent periods where calories get lower. Everything's fine. And there is mechanistic reason to believe that that could be promising because without

getting too deep into the physiology on short time, a hormone called leptin seems to be a really major driver of these metabolic adaptations during weight loss. And when we do have those high carb, high calorie days or even a week, we do see these spikes in leptin, which in theory should kind of help attenuate some of that adeption. But I will say that, again, it's the same kind of story with reverse dieting. Rather than tell everyone why it should work for the rest of my life, we actually did some studies. And unfortunately, when you do the studies, sometimes you find out that you've been wrong for a while. And so far, the research really hasn't shown us a good instance of these diet breaks or refeeds, having a huge impact on, you know, preserving metabolic rate or making weight loss, you know, substantially,

easier or more effective. There have been little hints. The places where they do seem to be maybe a little more useful, so far has been in studies where people actually lose a ton of weight rather than your typical college students volunteer for a study and lose four pounds in eight weeks. It just doesn't seem to be doing much in those contexts. How well does it work for people who are getting absolutely shredded? We actually don't know very well because it's hard.

hard to really study it in those groups. So all that is to say, I used to be hyper optimistic about that approach. Now my official perspective is from a behavioral perspective, sometimes people just enjoy it when they're dieting because it gives them some more flexibility, whether it's for a day or for a week here and there, whatever fits their lifestyle and their needs. So there can be some behavioral upside. There can be some performance upside if you're having your high carb day before a really big leg day and lower body is a muscle group that you prioritize. And then for the other elements of, well, could this maybe help me out metabolically if I'm about to lose 40 pounds or if I'm about to get down to 4% body fat?

For now, we have to put that down as a maybe. Yeah, that's a sign of an actual professional, a real scientist, like you're following the data. Like you used to believe something, new studies, new research, new data. and now your thought process is different as a result. It's a tragedy of the number of beautiful ideas that all the stupid data gets in the way, and then you have to change your mind. Terrible. That's why I only go for confirmation bias.

I only read the things that tell me I'm right. Unfortunately, I'm on Reddit and Fortune. It's so good to have professors like you guys that actually live it too. Like, I feel like in my, you know, when I was going outstate, I guess you could say, Like, well, Mike Stone, he did the thing too. You had like Megan Mike Stone who. Yeah. My name shows up in the same sentence.

And it's not because we all died on the same plane crash. I will have done something with my career. Agreed. And so it's good to see more and more professors that are living it too. You know, like not just doing the research, but doing the thing. Bodybuilding, power lifting life. And seeing putting your work. you know, putting it to the test.

Yeah, I mean, like you said, Travis, I mean, back in the day, there's just kind of this like handful, you know, the small group of people that like you're saying would would do the research, but also were really invested in it personally and, you know, would get in the gym and play around with the ideas. And it is nice for the field that now that's much, much, much more common. So, yeah, there's the field itself has just grown so much. I mean, Mike, you've probably seen this. like, you know, people, of course, people on the internet will trash exercise science research

every opportunity they get. And that's fine. That research is made to be discussed and debated and critiqued. But man, there's a lot of universities now where exercise science is like one of the fastest growing majors, some places where it's already becoming one of the largest majors. So yeah, just even just in, you know, I started studying exercise science in 2009. And even in that short time scale, the field has just really rapidly exploded in a very positive way. So I think we're seeing every handful of years another generation of graduates who are coming out,

getting out into the gyms, getting back into the labs and doing more research. And I think it's a rising tide for sure. Yeah. I mean, you're one of the people pushing forward the industry and coming on shows like this and people hear you and they go, man, that sounds cool. like I want to do research on on physiology and exercise and and strengthening so it's getting clear now it is it really is so one of the many reasons we have a lot of respect for you appreciate it coming on the show where can people find more about you social media any websites

product services the whole thing oh yeah so I'm on I'm allegedly on Instagram handles at trexler fitness but if you want to stay up with what I'm doing mostly it's mass research review that's mass research review.com to see what we're up to over there. And then I host two podcasts. One is called Iron Culture with Eric Helms. The other is called Front Page Fitness with Lauren Colenzo Semple. So if you like fitness and health-related podcasts, check those out. You might like them.

Yeah, right on. Lauren was just on Perform and then she was on Huberman here recently as well. So go check those shows out. I haven't listened to them yet, but they're presumably pretty awesome because she's great. Yeah. We've got to get Helms on here again, too. It's been many years since he's been on the show. We're right on.

Appreciate you. Travis Mash. Matchley.com. So you happen to be in the Penn State area. What's that college state? Like college. What is it? State College, Pennsylvania.

I'll be doing a USA weightlifting level once. First one I've taught in a long, long time. But I'm doing it mainly for the Penn State. The coach is there. But it's open to the public. It's July 17th and 18th. I think so right on yeah very cool uh dr mike lane yeah mike leight and phd i'll be at n scea national convention coming up in july uh literally yeah not i think it's like the 10th 11 12th so

feel free to say hi and be underwhelmed with how tall i'm not and i will be forever looking for mary mccheese i'll see you there man yeah awesome yeah uh very cool um i'm duck lauch on on Instagram at Douglas E. Larson. I actually am going to start coaching a little bit myself. I haven't coached in four years since the very beginning of Rapid. I haven't actually coached anyone personally. I've just been running teams of coaches, but I haven't actually personally coached any athletes,

and I miss it in many ways. And I was thinking what specifically or who specifically, what I want to coach. And I want to coach people that are interested in the exact same thing that I'm interested in. So master's jujitsu athletes. If you are a master's jujitsu athlete, whether you compete or not, recreation or competitive,

I would love to have a conversation. I just got my first stripe on my black belt last night. I pumped my own tires over here. Congratulations, man. Yeah. Congrats. Thank you. Thank you.

So yeah, if you're a master's jihitsu athlete and you want help with your strength, conditioning, and nutrition, DM me on Instagram, or you can email me, Dougabarbital shrug.com. Happy to help you out. Also, if you want to be coached by Mr. Travis Mash and Dr. Mike Lane, Dr. Andy Galpin, you can go to bowelmolecta athlete.com. That's A-R-E.

They can help you out there. Friends, we'll see you guys next week.