Welcome to the Empirical Cycling Podcast. I'm your host, Kolie Moore, joined as always by my co-host, Kyle Helson, and thank you everybody for listening as always, and I want to ask you subscribe to the podcast and share it with a friend. That really helps us out. iTunes ratings of five stars also helps us out, and also we are ad-free, so you can donate to the show at empiricalcycling.com slash donate. I have been flattered enough to have had advertising offers on the show, and they've all been turned down because your donations make this keep going. Coaching Inquiries, make us keep going too, so you can send those in to empiricalcycling at gmail.com. Also with consultations, we can look at any questions you want to know about your training or physiology or whatever. So shoot me an email there. If you have questions or comments about the shows, also contact me there and also on Instagram at empiricalcycling. My DMs are open. I don't... Check them that often as I should, but they will be checked, especially on the weekends when I'm doing the weekend AMAs, and we had some really fun ones this weekend, and a lot of people said thanks, and these are great, and I appreciate that, and we'll keep going with those. Kyle, also, I thanked everybody last time for the donations that they gave us over the last month and a bit. How flattering was it for you for those donations to come in? Oh, that was outrageous. Yeah, I felt, I was shocked. Genuinely shocked and super thankful. You know, it's cool. I think it's just another way that I think people can show that we actually have some sort of impact or meaning, which is kind of fun. Yeah, it is fun. And I got to get a new inline compressor for the microphone, so my audio quality is hopefully better than ever. Next couple big ones come in, I'll get one for Kyle too, why not? So let's move on to our main topic, which thank you for clicking our clickbaity title, the Fat Max Fallacy. So let's get to why I called it that. So in the last Wattstock episode, we saw that keto itself does not improve performance, despite that the studies that we looked at and many, many more all show that the markers or some markers of adaptation show improvement, but the actual performance did not show improvement. So the reasoning is understandable, I think, and correct, which is that carbohydrates are in short supply and the limiting aspect of endurance and most sport performance is indeed availability of carbohydrates among muscle power and oxidation power, like the usual list of stuff. So in theory, if we could get better at using fats overall, while still having the ability to use carbohydrates at times of high demand, then we can have better endurance and race performances and all these adaptations would make it worthwhile. Well, it's like Andy Coggin has said for years, like the best predictor of performance is performance itself, you know, because... Because I think at some level when I talk about kind of digging down into getting the adaptations that you want, a lot of times we can actually, this is one of the pitfalls of good science actually is reductionism, right? So we want to really, really focus in on a very narrow thing. So, you know, like Kyle, for you in physics, I'm sure there are some things where you go, oh, this is a thing that we find interesting, and if we do X, Y, Z, we'll find this, but also it may or may not include extra layers of things in between what you're studying and the ultimate end goal, right? Yeah, definitely. I mean, I think this actually, you run into this actually being a problem where, say you have some very rare phenomenon that you want to try to measure, and that Maybe you actually don't know how to measure that phenomenon, so you have to indirectly measure it. So you have to develop some metric or some proxy that you think gives maps well onto the thing that you actually want to measure, but that's too hard or too complicated or impossible. But then you may find later that the assumptions that you made to make that mapping from this proxy that you could measure to the thing you actually care about... doesn't hold up or some assumption that you made is not exactly true. So you may have some huge systematic error in the measurement that you made. And this has happened more than one time over years in different fields. And I think for reasons that are understandable, it happens a lot in particle physics and in cosmology, which is my field, because it turns out some of those things are really hard to measure, whereas like a lot not to... bag on condensed matter physics, but if your experiment completely fits inside of a regular-sized high school gymnasium, you have a lot more control over that experiment versus if your experiment is, I don't know, the LHC or building telescopes and instrumentation to measure things that are really, really far away, you sometimes have to get really creative, but you have to actually not measure the thing that you really wish you could measure. and so you can you could in theory develop a whole field based on doing this measurement that you find out later doesn't actually mean anything or doesn't mean what you thought it did to be fair with biology and a lot of especially any experiment that involves things that are alive and that you can't like immediately I don't know perform an autopsy on to like exactly confirm like like that's just super hard right like no one's gonna sign up for for uh extremely invasive studies if it requires massive surgery afterward or something to figure out whether their assumptions were correct or not. Like, oh, you want to come in here and then run on a treadmill or whatever and wear this funny mask? Fine, but you're not going to take a chunk of my leg muscle or something, even though a biopsy is not a huge chunk. It's still like that's even enough to deter people, let alone anything more invasive. Yeah, and I think also it gets to kind of what we're getting at here is like when and a lot of studies look at markers of, you know, like PPAR or PGC1-alpha or, you know, the COX kind of stuff or, you know, even CPT expression and things like that or mRNAs. They're looking at markers that we associate with good performance because, you know, high performance have a lot of X, Y, or Z and therefore if we see an upregulation of this, that, or the other thing, So that's something that may, and a lot of the language in these papers that I've been reading are very equivocal and for good reason, because they may associate with XYZ. And so we're going to take a good look at a couple papers today. And the first one is the original Fat Max paper. So this is the one by Oskar Yukendrup and Yul Achten, which I'm hoping I am butchering those correctly. They coined the term FatMax that I'm aware of. This is originally published in 2001. So what is it? It's the intensity where, quote, unquote, fat oxidation is maximal. So it's pretty simple. In the paper, they look at fat oxidation in grams per minute, which is an interesting way to look at it, I think. Because it's where the work rate is high enough to require energy. But not quite high enough that we're getting the fat transport inhibited. So this paper, the original Fat Max paper, looks at theoretical uses. It's LinkedIn that's shown us, by the way. So it looks at theoretical uses of knowing the exercise intensity at which fat is maximally burned. And this is a good paper showing good equivocal language in a scientific paper. It says it may be useful for improving diabetes. Training at Fat Max could, and I'm quoting here, could at least theoretically result in optimal adaptations in these pathways. These, quote unquote, referring to fat transport and metabolism pathways. And also training at Fat Max might increase weight loss. So for 2001, I think it's a really good paper. And this is good language. Yeah, I think it's interesting because a lot of times now, people, immediately want to take away of like, oh, this paper says that X, Y, and Z training will make me better. And to approach it entirely from this theoretical, oh, this, we have coined or identified this particular regime. And here, now that we have like a name for it, it's easier to talk about what are the good things that might exist, right? Because that's how you can kind of tell it was a brand new thing. because they didn't have a backlog of 50 years to say, oh, we've been looking at FATMAX for 50 years and this is what it looks like. This was a new idea. And so this language does remind me of in physics or something, if you see a paper that comes out, oh, we made this measurement and we don't have enough statistics on it to say that we definitely discovered something, but this could hint at this new physics or this might be an indication that X, Y, and Z, is or is not a correct assumption based on ABC, for example. Yeah, and I think this gets to a translation issue between scientific literature and the general public because a lot of the times when people latch onto a certain thing... in science and translate it into such a thing as we can bring it to the general public. Like in WKO 5, I feel like I was instrumental because I asked one of my friends to program this for me and we worked on it together in bringing the force velocity curve. into something easily accessible for people with just your regular aggregated data. And the question is, how do you use this kind of stuff? And it's a question that is a good question. If you know your optimal RPM, the cadence at which you make the most power, how do you use that in a race? The question, I mean, you kind of can't unless you're on a track and you're just... You know kind of the speed that you're going to achieve and you can gear up and down for it. But if you're on the road, if you're in a crit, like nobody's looking around going, hey, hold on, let me, what cadence am I at? Don't, hold on, don't sprint yet. Yeah, yeah, yeah. And so when it comes to things like Fat Max, I think a lot of people don't realize why they're riding at Fat Max or why they're trying to find it, what they think is necessary about it. So before we get into that for a second, let's actually talk about where we find FADMAX. Because when we look at a lot of the papers, it shows a pretty good arc. Is it a hyperbola or a parabola? I'm going to call it a hyperbola for now. And it's an idealized hyperbola. And the x-axis is pretty short compared to what you might see in an actual... actual test with gas exchange and whatnot. And it looks like it has a certain peak and it should be pretty easily identifiable. Like, okay, here's our fat max and we go a little to each side and we're going to lose about 0.1, 0.2 grams a minute or something like that. But in reality, some of the data I have for one of my pro athletes, his threshold is about 400 watts and his fat max range, where he's burning the most grams per minute of fat is between 180 and 300 watts. So we have a 120-watt range, and this is going to come into play a little bit later. But I think it's really interesting that a lot of people think that Fat Max might be, well, we're talking about what is Fat Max. I think it's interesting that in reality it's not a You know, very small range. It's actually pretty large. Yeah. I mean, that reminds me a little bit of the, what is VO2 max power? You're like, surprise! It's not a specific power, but, yeah. And so, for this, in this individual, if you were like, oh, go do a ride at FatMax, there would be a follow-up question of, where? You know, like, I know before we said, prescribing too precise of a, of a power target for a workout is not ideal, but this seems like too large of a range. Yeah, what are the fat max fallacies? Let's get into this. So I have two here. One, the first one we're going to go into quite deeply. The second one is actually fairly simple to answer, and it actually hints at a lot more episodes that we're going to get into, a lot of stuff we're going to get into in the future. So the first one here, riding at maximal fat utilization rates will not, in and of itself, get you better at burning more fat beyond what you normally would get from just riding at endurance pace. The second one is that burning more fat does not mean you're losing more weight. And so let's, okay, let's get into the first one. So when we talk about aerobic adaptation, usually when we think about aerobic adaptation, we think increased VO2 max, increased fat reliance on carbohydrate sparing, You know, the typical range of things. So I spent a very long time. I think, Kyle, I told you I had read about like 100 some odd pages of research papers. Yeah. Total is now into the mid 200 page range for this episode of reading because I wanted to make absolutely sure that I could say that statement with relative confidence while knowing all of the asterisks. that exist. And there are a couple small ones that we're going to talk about in future episodes, but for now, the idea is that just riding at maximal fat utilization is not going to get you extra aerobic adaptation. So, let's get into this. So, there's nothing special, basically, right? Like, there's nothing necessarily special as far as training goes. For Riding It, Maximal Fat Utilization. Well, I think one of the interesting things here that we're also going to talk about is that this kind of shows that there's no such thing as exercise in a pill. Because I think, Kyle, you had typed this in one of our shared notes things about, you know, the exercise in a pill thing or whatever that was. And there are such things out there like, I don't know how to pronounce it, ICAR, A-I-C-A-R, which is an AMP memetic. and it actually doesn't do anything because no matter how many mitochondria you have in response to taking this and having increased AMPK activation and yada yada, you're not actually going to be spending any kilojoules and spending energy is sort of the essence of exercise. I don't know if I'm crazy here. I don't know, Kyle, what do you think? Yeah, I think another maybe more straightforward example would be, like, why can't I just drink a bunch of caffeine, drive my heart rate and blood pressure up, and get VO2 max adaptations, like, sitting on my couch, sweating, and, like, having the caffeine shakes, like, well, it turns out, even though doing VO2 max efforts, like, you get higher blood pressure, and you get higher, you know, stroke rate, stroke volume, like, you don't, you miss out on a huge component if you're just drinking a lot of caffeine and sitting on your couch. Yeah. Well, and so like, like I car, a car, I don't know. Um, it actually, so like I said, it activates AMPK and it, you know, turns on that signaling pathway, but this means that the Anabolic signals that you have at rest turn catabolic. So the anabolic meaning muscle building, or not muscle building, just like the building anything in general, like restoring glycogen and blah, blah, blah, it turns them off because you're telling your cells like, oh, hey, we are using energy, we need to fix this. And so the cell shifts priority as it should because evolution is pretty smart, I think. No. Okay. So this actually reminds me of a lot of people ask me in jest, but some of them occasionally it's serious. And, you know, don't make fun of these folks because I thought the same thing back in the day. So I don't have a leg to stand on here. It's that when people say, oh, my heart rate, like this morning was the last F1 race of the season, my heart rate got up to max. Like how many TSS do I get? The answer is zero because Your, I tell them my canned line is you get zero because your cadence was zero. But there's something really important in there, which is that cadence is something called muscle contractions. Okay, so let's get to muscle contractions. So we need to talk about order of operations again. This is going to be a lot like the VLA max discussion where Energy gets utilized and then metabolism fills in based on the rate of demand and other factors until homeostasis is again reached. Should it be reached when you stop contracting your muscles? You would stop running away from that lion and it's time to sit down and have some potatoes again. So because this is Wattstock, let's get more technical. So nerve impulse comes in. The sarcoplasmic reticulum releases calcium, which binds troponin and moves tropomyosin out of the way of the actin filaments, and so myosin can bind, and the action of the myosin head, contracting the muscle and, you know, pulling the two sides of the sarcomeres together, this consumes ATP. Notice there's no fat in here either, the same way there was no carbohydrates like in VLA Max. Right? So we might consider an analogy of metabolism, and I'm going to stretch this a little too far. I apologize ahead of time. It's like two bucket brigades. So your carbohydrate brigade has a smaller pond to pull from, and it can go really fast, but a little too fast, and you can get pretty tired pretty quick, right? But the fat brigade gets to draw on the world's biggest lake and does not fatigue, but the buckets come in very slowly. And so consuming ATP is like a fire in that it's releasing energy, and the bucket brigade's job is to resupply ATP, which I guess keeps the fire going in this analogy. So I told you it would go a little too far. So anyway, the muscle only cares that it's not inhibited in its contraction. And if it's not, when it gets the signal, it's going to contract. I think that's a pretty important distinction, the same way we had to make it with the VLA Max, right? Yeah. Yeah, I mean, I think, and we talked about this before, right? Like, when you're actually looking at the muscles contracting and using ATP, at some level, they don't, yeah, they don't care where the ATP came from. And you can even go up before that when you talk about, like, the Krebs cycle, you know, the, your body doesn't, hasn't, like, specially marked some of those, you know, NADs or whatever. It's, you know, this one's from... This pyruvate is actually from fat oxidation or... Glycogen, you can't tell once it's been broken down far enough, right? Like they're not special some way. Like these are the special fat ones and these are the special sugar ones over here. Yeah, what's important is the rate. And if the rate is high, then your body has to supply it with the faster metabolic pathway. And if the rate is low, then your body can supply it with the slower metabolic pathway. And you can improve indeed those fat metabolic pathways, the fat burning ones that save your high energy carbohydrate stuff. This is all, you know, Coaching and Bioenergetics and Sport Performance 101. So let's dig deeper now. So muscle contractions are, like we just went over them, they're critical for us to understand because the muscle... already understands this kind of stuff. We don't want to impose our will on the muscle because the muscle is going to prove us wrong every time, just like when we're doing experiments and we think we're measuring a thing and we're not, then it comes out in the end. So substrate availability on its own and even with most training, like see the last episode on keto diets, these can change various markers for utilization and substrate use. But I've never found a case where you get faster by just that alone, right? You need to do the training. And what counts as training is muscle contractions. So this is a very, you know, sorry, I feel like I'm talking to kindergartners, but I think this is really crucial to understand. And so we're, you know, this is like saying one plus one equals two, but we're going to make it philosophical. How does the muscle know? Doing the sport helps you get better at the sport. So how does the muscle know the difference between we are exercising and we need to use more fat, right? So to detect endurance exercise, muscles look for many signals, but right now we're only going to look at two because these are the most common ones and they're two of the oldest signals that we know of for aerobic improvements. Elevated Calcium Levels in the Cell, and AMPK activation, right? So I know it might be simple, and it sounds very simple, but a huge amount of things in a muscle cell detects elevated levels of calcium, and that can lead to aerobic adaptation via PGC-1-alpha and mitochondrial biogenesis and the whole shebang. Like, if you just go into PubMed, and look up calcium signaling and mitochondria or something like that. And you're going to go, wow, this is a lot of papers. Yeah, it is. Yeah, everybody's known about this a long time. Presence of calcium does a lot of things in a muscle cell, elevated over normal levels because obviously we always are going to have some. So if you take a slice of muscle and you put it... In a solution equivalent to normal resting calcium concentration, nothing's going to happen, right? And if you make the concentration pretty high as if your sarcoplasmic reticulum has gotten the signal and has spilled out its calcium, the muscle's going to contract, right? And then the muscle's going to stay contracted until it either runs out of ATP and then everything kind of relaxes like rigor mortis or you dilute the solution and then the muscle can relax. If you give it just enough calcium to avoid contraction above your baseline levels but not high enough to make it contract, you actually end up with mitochondrial biogenesis. So this is one of the things that we saw in Wattstock number 28, by the way. Now, this looked at high-intensity interval training cause fragmentation of reanodyne receptors. and this led to sarcoplasmic reticulum leak of calcium into the cells and this led to a good amount of muscular aerobic adaptations that actually were indeed visible in performance. Right, yeah. So I think that is a pretty good example of this signaling pathway at work. So AMPK is the other one. And we're going to have to go into AMPK probably several more times over the life of this podcast and probably the entire life of science. It's a really important signaling molecule. And this is the one that we mentioned in relation to ICAR, the exercise in a pill, which actually has the cute little name, Exercise Mimetics. We're going to mime exercise. We're not going to do exercise. We're just going to mime it. So AMPK is one of the energy sensing signal pathways. So during exercise, AMP levels rise due to muscle contractions, which means AMPK gets more and more activated and starts to shut down the ATP-consuming rest and digest anabolic pathways. in order to activate carbohydrate and fat utilization pathways, or catabolic pathways. And this was discussed in Wattstock number 33. So ICAR does this by chemically being similar to AMP and blah, blah, blah, the whole thing. Just this, just this little bit of AMPK directly phosphorylating PGC1-alpha is one of the many, many, many, many ways that all of the transcription factors, stabilizing things, and mRNAs, and like the whole way down. Like it's very complicated to look at and people are still looking at and discovering things in this. I think this kind of gets to a question that a lot of people have right now is, so how do we connect the science to the performance? Based on currently available evidence that I've read, which I guarantee is not comprehensive because there are thousands of pages about this stuff and I've only got so much time. There's nothing in the whole body. Or muscular-specific aerobic adaptation where burning more fats is better or worse, or burning more carbs is better or worse in and of itself. So if you change what you can burn based on, let's say, diet, this can improve some markers, but it does not necessarily improve performance. That makes sense. Kind of like we said before, you're... Your body cares, but it also doesn't care, say, with diet manipulation, right? Like, your body's going to be like, well, this is what I have available, and this is what we have to do. So I'm going to make this work so we don't die, effectively, right? Like, if your body was completely rigid and refused to be able to switch fuel sources, In a hypothetical situation where you are some sort of prehistoric human and it is a bad season and you didn't, I don't know, harvest enough and you also can't, and so you don't have enough carbs because you haven't found enough fruits or whatever and you only ate meat or something like that, you would die because your body wouldn't be able to adapt. It would be nice if it was always a one-to-one, especially for science, right? It would be great if you could always measure some marker and then that definitely only had one conclusion that you could reach from making some measurements. Science would be a lot easier. Yeah. Well, I remember there were a couple of papers that Keith Barr wrote way back in the day and he was instrumental in uncovering mTOR and PGC1-alpha and their relationship with everything. And, you know, obviously a lot of other scientists too, but he's the one who's on all the... Podcast and written the articles and all that kind of stuff. So I think about him. Sorry for anybody I'm sliding here accidentally. One of his papers had an R-squared value of 0.99 with some certain exercise duration or something like that and expression of PGC-1 alpha or mTOR or something like that. It was one of those things where you look at it and in normal science you think, definitely asked the wrong question. I'm measuring the wrong things. There's no way this actually works like this. Right, yeah. And it was one of those rare instances where it was kind of like finding a point mutation for a disease like sickle cell. Sickle cell is a point mutation, and it was found really fast and really early. And from then on, you know, genetic basis in disease has been extremely complicated. Like all the easy stuff got found out pretty quick. Like we found out one plus one equals two and two plus two equals four pretty quick. And now there's like, you know, very esoteric branches of math. Yeah. I mean, that happens in every field, right? That's definitely been the case for modern physics. People talk about, oh, all these developments that we've made, say in quantum mechanics and... Relativity and all this stuff from the early part of the 1900s all the way to today. But all of that, the heyday of particle physics was them discovering things that were much easier. And that's why it took however long to find the Higgs boson, right? Because all the other easier to find, easier to measure particles were already measured first. You know, I think what we're kind of getting at here is that, well, let's also not forget that a lot of people got very fast doing a lot of long endurance rides while eating carbohydrates. It's understandable if you are a professional on the cutting edge of competition and you need an edge, you're going to leave no stone unturned in your pursuit of an Olympic medal or a world title or something like that and so you're going to try all these things and naturally some of those are going to filter into the popular level topics and articles and messing around with diet has certainly been a popular one. the last many years. Yeah, and diet manipulations can certainly have impacts like measurable performance impacts on aerobic adaptations, but it's not necessarily like the way that you think it happens. It happens from other things and you still need to do the training. It's like in Tyler Hamilton's book, what was it, Secret Race? He talked about you could take all the drugs in the world, but you still had to go out and ride. Like that was very much impressed upon the reader about like what happens when you dope is you still have to go train. You know what I mean? And so you can do all these diet manipulations and whatever, but you still have to exercise. And so I think, I think kind of, again, like we touched on this earlier, but I've written a couple of points down here that we should think about when it comes to connecting the science with actual training and performance improvements, like measurable in all dimensions. Yeah, I think it makes sense. All these measurements, especially on their own, are all a relatively incomplete picture if you're just looking at one thing versus looking at this rather complex system as a whole. It would be nice if all of these markers or individual measurements you made only had one. Implication. But unfortunately, especially as systems get more complex, and as we said, the human body is extremely complex and well-regulated for a lot of these things, there are multiple implications that could be true and also could be not true given the same measurement. Like, you could make one measurement and then go back later. and come to a conclusion and then realize, oh, no, there's actually a few options and you had to do four more measurements to figure out which one of those options is actually correct. Yeah, yeah. I mean, and that's why I kind of like Louise Burke's studies of racewalkers is that they measured actual race performance in people as opposed to, you know, as opposed to just measuring certain markers and calling it a day. You know, I really like that she took it to that next level of actual performance and I like a lot of studies where They look at time trial performance or they look at sprint performance or one of the studies from our early in the podcast where we looked at keto-adapted diets and they had people ride for like two, three, four hours or something like that and they had them do like one in four minute maximal efforts during that thing to kind of simulate like a race day and I thought that that was a really interesting and fascinating protocol. I really like that kind of stuff. Yeah. And you have to imagine too, in order for a research team to come up with those measurements, they must be slightly more connected with actual sports performance and not just be more on the laboratory measurement side because there are lots of ways where you, maybe for some other more pure research-based endeavor, you could want to do a study, say, about keto or diet manipulation or whatever and want to measure these markers and then move on. And if that was not done at all with a sports performance goal, if it was just on, oh, what happens to the body when you do X, Y, and Z? Oh, this happens. Okay. You know, that in of itself is a finished result for some people in some fields, right? Like, they're like, okay, great, yeah, that's what we wanted. But then to... You know, you're basically misapplying the science if you take that and then immediately jump to, oh, this must mean X, Y, and Z for sports. Yeah, and actually when it does work like that, I mean, it's fascinating and it's really useful and it's like, whew, dodged a bullet. It could have been a lot more complex. Yeah. Okay, so I think this brings us to one of the last points that I wanted to make right now, which is that, you know, when it comes to using a substrate, You know, this is kind of one of those happenstances where, you know, at first glance, it can actually seem very promising where, okay, you're using more fat, you're using more carbohydrates, so therefore, wouldn't the body want to get better at the things that allow us to utilize this kind of stuff? And actually, that's exactly what we see when we do diet manipulation and kind of stuff like that. When we do diet manipulation like we've seen with keto, it does not actually lead to performance enhancement despite the fact that it does lead to markers of enhanced fat transport and enzymes and stuff like that. So there's a very important distinction here because if we were going to actually really see... just burning more fats in and of itself. We would see keto be extremely effective at enhancing endurance performance, but that's not what we see. And so what this really makes me think of is the fact that the body is actually reticent to add more actual performance enhancements than it actually has to. So if you are burning more fats on a ride through manipulation of power or diet, or any kind of thing that does not necessarily mean your body's going to go, oh, we need to make all these aerobic enhancements. Like, you know, if you're eating a lot of fat, your body's going to increase the amount of fat transport it can have, but that doesn't necessarily mean that it's going to improve performance, and that's why we paralleled with quote-unquote exercise memetics, which are there to Kind of stimulates some signal chains to yield some adaptation, but does it yield all the adaptations that we want? No, the fact is pretty much that it doesn't. And so let's say we have a certain manipulation where we can ride for two hours and four hours, and for both durations, we can actually burn the exact same amount of fats in grams. The longer ride is going to yield more adaptation, in my opinion, and according to the... Research I've done, so I'm ready to be wrong on this, but it's going to take a little while to prove it if it's a thing. And I'm talking performance enhancements. So if we do the two-hour ride and we burn less fat, it's only two hours of calcium signaling, of AMPK activation, and yada, yada, yada. And so therefore, it's actually not going to yield the whole systemic adaptation that we want. And so I think that is a pretty important distinction here. but really what we want is like blood volume, we want capillary density, we want all kinds of things and when we actually ride we develop the whole range of adaptations. That is why even before we had all of these studies people knew that some sort of progressive overload was important. Yeah. Because if you could get super strong Just by doing 2x20 at 200 watts for the rest of your life, that would be awesome. Yeah. Well, I mean, Tim Cusick talks about this in the WKO webinars all the time, which is the SED principle, the specific adaptation to imposed demand. And it's a really good way to look at it because I've thought long and hard about how do I apply this to something? Like, what are the training implications of knowing these facts? proportionally to the amount of stuff I know, to the amount of stuff that I can successfully apply to improve performance, it's disproportionate to say the least. Yeah. It's not the ratio you would like it to be. No. And it's, well, I mean, that's why there's not more podcast episodes, I think. It's because I'm like, if we actually want to help people improve their performance and show how I help people improve their performance based on what I know, It's not like every paper you read is a home run in terms of, oh, now I do these intervals this way. It's a very, very, very long process, unfortunately. And that makes sense. Like, that kind of goes hand in hand with the fact that not every idea or every measurement someone has ever made in science has resulted in a Nobel Prize, right? Like, not everything is going to be super cool. Like I said before, some of these things might be just doing measurements to sort of round out or complete some set of measurements. Or you perform an experiment and do some measurements and that brings it in line with the other state of the field or the sort of expected results or expected style of paper or style of study that is common for X, Y, or Z fields. And that may not immediately result in a... Awesome, like an amazing new interval style or whatever you would want it to be. Yeah, so. Yeah, all right. So I think let's kind of move on to the next Fat Max fallacy before we totally beat this one to death. And then we can beat it to death a little more when we're wrapping up. So, you know, we still haven't touched on Will riding at Fat Max help you lose more weight? Right? Now, is this too good to be true? Is this normal? Is like, how, how are we getting, how would we get such a thing? Because don't forget that we can not exercise and still lose weight. Right? So, yeah. Let's talk to Uncle Thermodynamics for a second. That's my name for you right now, Kyle. It's Uncle Thermodynamics. Lisa. In this house, we obey the laws of thermodynamics. So let's talk about the mass-energy relationship because I think a lot of people think that in order to lose weight, you need to ride in such a way to burn a lot of fat. But when you look at people who do high-intensity interval training, They can lose weight too. When you look at people who are sedentary, they can lose weight too. They're not riding at Fat Max while they're sitting on a couch eating less Twinkies than they otherwise need to maintain their body weight. So how does this work? Well, the secret here is, fortunately or unfortunately, it's pretty simple. It's that to first order, if you expend more calories than you are intaking, Tend to Lose Weight. Now, this is a basic, like, you can call it an extension of the first law of thermodynamics, kind of, because, you know, it says energy is neither created nor destroyed, you can just turn it into different types, but basically it's just a matter, for the first order, it is a matter of a basic balancing of what your actually, body's actually burning, and how much Food, or how many calories you have available at any one time. And to first order, your body is fairly ignorant about what kind of calories those are, if they're all strictly following a keto diet or not, like your body isn't aware of that. Yeah, definitely. And so that's why you can do, you can, a lot of, a lot of more modern diets that aren't, that are actually trying to be founded in science. Typically start off with a rough calculation of how many calories it takes every day for you to maintain your weight given your current weight. And then they say, okay, so your first order is eat like 500-ish calories fewer than that number. And because that number that they initially give you based on your body weight may or may not be exactly accurate given your age and how much muscle mass you have, blah, blah, blah, then they adjust that later on. It doesn't care whether you are actively exercising a lot or not. You can just follow the plan and adjust as you go. Well, I think it's difficult for a lot of people to figure out how many calories they're actually using. And actually, the hardest thing is people have a hard time figuring out how many calories they're actually consuming. Because proportion size, did you know a tablespoon of peanut butter? is actually pretty small. Like, it's not the whole jar. Oh, yeah. Yeah. Yeah, it's weird. Yeah. I mean, you'd think they would have, like, a, you know, someone would advertise this by now. Well, that, and I also think that if you are a, like, you can read the back of the labels, and even if you are someone who knows, like, oh, about how much a tablespoon is, the vast majority of people aren't out there weighing all their food which is like if you're a Mr. Olympia bodybuilding competition and you are having to get just like ridiculously shredded that's what all those people have to do they literally have a food scale and they're weighing out all their food and because they do have to be so precise and it does matter but for the vast majority of people they don't have to be precise down to the 100 calories a day or something to hit their goal and It's just tedious, right? Like, no one wants to wait. You don't really want to say, I don't say no one. Some people do want to weigh their food. But, yeah, it can be hard because you aren't, it's your first thought when you're like, oh, I'm going to make a peanut butter and jelly sandwich. Oh, got to get out the food scale and weigh how much peanut butter I put on the table. I've done it. It is a giant pain in the ass to, like, be on a diet and weighing your food. But, like, once you get used to the proportion sizes, and you're like, oh, I actually only need about this smallish handful of whatever to have my carbohydrate needs for the next four or five hours. First, it's depressing. And second, you know, you go through the day and you're like, I'm not hungry, but I'm still losing weight because you're in a deficit. And that's, I think one of the most important things here is that it's important to note that the, well, because this is Wattstock, right? So let's really dig into this. So it's important to note that the energy we expend is stored in chemical bonds. And we've actually spent the last few episodes going into this in very great detail, right? So carbs and protein have about four kcal per gram. That's kcal of energy, energy available to do work, even though technically we lose a whole bunch of it to heat, whatever. So fat has more, about nine kcal per gram. So remember in previous episodes, we discussed this as being energy. Density. So when we store fat, we're storing energy, which is a dense and efficient way to store it. Otherwise, we would have to have more than twice as much volume in carbohydrates. And so carbohydrates and protein can be converted to fats to store energy. So fat and protein can also be turned back into carbohydrates by the liver, which is why someone eating zero carbs can actually maintain a blood glucose concentration in the normal level. So the body knows how to convert substances between each other to make use of its appropriate energy needs, right? Here's the thing. Empty fat cells are hungry and they will take up whatever substances they need to make themselves whole. They can take up glucose, they can take up fats, they can take up proteins. So the math, if we want to do the math, works out to something like this. If you ride for five hours, you'll burn about, if you're riding at one, Gram of fat burn per minute, which is high, but that was my pro athlete example here. He can burn maximally about one gram a minute. So if he rides for five hours, he's going to burn about 300 grams of fat or about 0.6 pounds, which is 2,700 calories worth. So does this mean if you don't eat 300 grams of fat that you're going to keep that fat off? No. Obviously. Well, it might be obvious, it may not. So if this is new to you, that's cool. At some point, it's new to all of us. So really, you would actually need to go without all 2,700 calories. Not just in terms of fat, but calories just in general, the energy. And running that kind of deficit in a day is murderous. So you burned all that fat, but you don't actually get to keep it off. Because if you do, your body's gonna be really, really in a bad place. So if you want to maintain your weight also, does this mean you need to eat back 300 grams of fat? Okay, also no. So the body already knows the first law of thermodynamics, which is why just plain burning fat is only half of the equation. And it's also why if you're sedentary and you're running an energy deficit, Guess where we have stored energy? In our fats! So if we're running an energy deficit, the body goes, oh, we need more, we're not eating enough, let's go grab some extra stored fuel, it'll do that. No peddling needed. But there's also no aerobic adaptations that way either. Because this kind of gets to the episode wrap-up, which is, why does Fat Max riding seem to work anyway? Like, why does it seem to improve us aerobically, and why does it seem to help us lose weight? Even though when we look at direct consequences of riding at these intensities, they don't enhance these things. And I think that's an important distinction is when you are doing the riding, you are causing aerobic adaptation to happen and you are expending energy, but you are not adding any additional adaptation by By burning more fats. Otherwise, we would see people doing keto diets, like just shredding all of the aerobic adaptations. Like they would just get, like they would be the aerobic equivalent of Mr. Olympia or Miss Olympia. Right. Mrs. Miss. But, and the same thing happens with spending energy is these are You know, if we look at my athlete, his fat max range in grams per minute, he's burning about one gram per minute, you know, between 180 and 300 watts. His endurance pace is in the middle of that. Does he have to ride at 300 watts to be burning a gram a minute? Like, not necessarily. He can ride at 250 if he wants. He can ride at 200 if he wants. That's fine. But when you kind of get up to... You know, your sustainable pace, that's your, you know, your endurance pace, that's, you're going to finish feeling good. You're not going to be too empty. Even if he eats, by the way, like 100 grams of carbohydrates an hour, he is still going to have enough energy deficit by the end of that ride that it doesn't matter that he's been eating. He's going to have ridden a ton. and he's going to have expended a lot of energy. And so looking at the crossover or the overlap between Fat Max and just general endurance riding, there is a lot of overlap. Does that kind of make sense? Yeah. And I think additionally here, if there was, if you are, say not necessarily for someone who's worried about racing and training, to actually compete, but someone who's just at the gym on the treadmill or spin bike or something just sitting there to try to lose some weight, try to increase their calorie expenditure for the day, the idea that you have to sit at Fat Max instead of working a little bit harder, if you just calculate how much work you would do, you would burn more calories, and who cares if they're fat? If you work just a little bit harder above Fat Max, say, you know, that's kind of right in that endurance range. So if you're only going to go for a gym for an hour and sit on the spin bike and you're going to do so at zone two effectively, if you're solely just worried about losing weight and not about training, why not do it at zone three or something higher where you're just going to burn more calories if we know that calories in versus calories out to first order is the most important thing. Yeah. Well, I mean, because I think it's more sustainable to bring it down a little bit from that, but it depends on how long you're going. Like, if you're going to ride for 10 minutes, yeah, very different set of equations here. Because, like, you can burn 4,000 kilojoules on an endurance ride. It's hard to do 4,000 kilojoules with hill reps. Oh, God, that sounds terrible. Yeah. Yeah, I mean, it's... Doable, you can do it, especially if that hill is like, I don't know, Von II, but, are they called hill reps then? If it's, you know, it's the Galibier, we're gonna do hill reps, like how many reps do you get up at, yeah, no. But yeah, I think that's where the Fat Max thing kind of, to me, feels like it bleeds over from sort of popular level fitness, is that it, that idea of working, of doing all of your aerobics, quote unquote aerobic work or conditioning work at Fat Max because you want to lose fat is a very big thing that you see on these posters or even physically on the screens on treadmills sometimes when you go to the gym and you're like, why? And yeah, they just took a paper like this one and made the wrong, like extrapolated from it and made the wrong conclusion. Yeah. I mean, and You can't blame people for that kind of thing. I mean, I've had this misconception myself. Like, I've done this myself. Like, oh, I'm going to do what I can to increase my fat oxidation. Like, I'm going to eat less carbohydrates, and I'm going to eat more eggs and vegetables, and then I'm going to go out and ride, and I'm going to lose more weight that way. I actually, I thought that, like, way back in the day, in like 20... 11 or 12 or something like that. I was doing that because I was wrong too. And so maybe the whole premise of this episode is just a projection. And if that is true, then I completely accept that fault. That's fine. And honestly, it's definitely a misconception that lots of people have, right? Especially when keto started becoming popular or Adkins or South Beach. Looking at it though, what you just described, like eating more fat and more vegetables and protein, those are the things that end up keeping you feeling full anyway. So that's not necessarily a bad thing, right? Especially if you're trying to eat a little bit less and lose a little bit of weight. If you find that you're staying fuller or feeling fuller longer, that's going to help a lot. You can imagine just eating, I don't know, the opposite is like eating tablespoons of sugar over and over and over again. You never get full. Well, I think the conclusion, right, is that it's not that Fat Max is bad. There's nothing wrong with it. It's just that it isn't special. Kind of like when we talked about keto. It looks bad for a sports performance, but putting sports performance aside, it's fun to bash on keto, but there's nothing inherently bad about it. There's just not anything that makes it extremely special regarding... if you're going to go out and try to be an elite race walker. Yeah, you know, there's no, like we've said a lot of times, and a lot of people have said a lot of times, there's no silver bullets here. And also sometimes just putting in the work is also not enough, like, because what is the work? What is the quality of the work? If you go out and you do 30-second sprints four days a week and you do that for 10 years, is that going to be... the right, the best training to make you as aerobically fit as possible? I would argue no. And also if we just, if we do a lot of keto and we do a lot of low intensity riding, is that going to do the same thing? I would also argue no. It's like you've got to put in the appropriate work at the appropriate places and that's what's going to bring you the farthest. And in my experience and to the best of my understanding, All of the little, oh, maybe we can increase a little more adaptation here. We can do a little bit more signaling here. All that kind of stuff really is not going to be the difference between you making it to the world tour and you staying a local Cat 3. Yeah, that was picking your parents. You got to pick. Yes. Yes. All it really does, all these little things. What they do is they help speed the process up. And I wouldn't even say that it's within power meter measurement. It's just that when I look at things over years of working with somebody, I think, you know, can this person have improved a little faster? Could they have another 10 watts of threshold? Could they have a little better endurance at this point? Could their sprint be a little better if that's something that we need to work on? You know, I think in like year cycles, you know, if I'm working with somebody young, I think, okay, well, how do we get this person to their full potential before they kind of age out of, you know, going to the world tour or wherever their potential is? You know what I mean? Yeah, so the Fat Max fallacies, you know, it's funny, I think as a final note here, I've asked a couple people. what they think of Fat Max Training. And a lot of them have said, what's that? So maybe not the most popular thing here, but I think for people where they want to think about Fat Max Training, I hope this episode helps kind of put it into perspective. And I think as a very last question, Kyle, I want to know if E equals MC squared applies to You know, energy expenditure and, you know, losing fat and whatnot. That's an interesting question, right? So we've talked a little bit about this before, like where does the energy come from when you actually break down carbohydrates and fats? And we went over that in fairly gory detail, but we never mentioned E equals MC squared. And even though if you are someone who's never taken biology and maybe in... to a deep level and never taken physics to a deep level. You might say, hey, oh, energy equals something related to mass. Is that how I get energy out of the food I eat? And it turns out the answer is no. And that's because- I don't have to ride at the speed of light to lose fat? Right. Yeah, exactly. You both don't have to work at the speed of light, nor are you actually, is your body physically capable of taking advantage of the way that E equals MC squared. This formula famously is part of Einstein's energy mass equivalence formula. And the best example that people are maybe familiar with about this is a large particle collider like the LHC, the Large Hadron Collider in Geneva, Switzerland, where they're actually able to take particles that are lower mass particles and slam protons and slam them together. at very, very high speeds that are at very, very high fractions of the speed of light. And they're able to take that and actually make particles that have more mass than the two protons that went in. And that's because they're literally converting the kinetic energy of those protons into mass. Another way you could think about it is if you have a really heavy particle or even a lightweight particle, If somehow you could completely convert that into photons, which have no mass, the amount of energy or light that you would get out if you could somehow spontaneously turn an electron or a proton or one of these things into light is equal to the mass of that particle. But your body is capable of doing neither of those things. So unfortunately... So if I move fat through the LHC... at such a high rate. Can I convert it into carbohydrates at the right speed? Maybe, maybe. I mean, so the thing is, at the LHC, they're typically only slamming nuclei together. So at that point... Fat and carbohydrates are made up out of the same nuclei. At the core, they're either carbon or hydrogen. All right. Well, maybe I'm just going to stick to colliding it with my mouth. Yeah. Between your teeth is a pretty good speed, right? That's like, you know, millimeters a second. Sublight. Sublight. Fractions of the speed of light. Except if you see that donut, then you maybe start moving at faster, at a faster speed. The appropriate thing. Alright, so anyway, all those show notes are going to have the references to, I'm actually going to put up a couple extra papers. One of them that I read was my One of my favorites because it's titled Exercise. It's the real thing. So like talking about how there's no such thing as an exercise and a pill or something like that. So I thought that was pretty cool. So check that out at empiricalcycling.com. So if you've got any questions or whatever, or if this episode upset you or you think we got something wrong, also let me know. I have been corrected by our listeners on many occasions and I will continue to learn like that. So I appreciate that. Thanks for listening. And if you want to donate to the show, that keeps us going. That's at empiricalcycling.com slash donate. Coaching inquiries also keep us going. So if you want to inquire about a coach, we are always taking on athletes. We have a couple coaches with roster spots right now. And when we run out of that, I add more coaches. They're getting really hard to find good ones. But rest assured, we have plenty of roster space right now as we are set up. Shoot me an email, empiricalcyclingatgmail.com and consultation stuff, we can answer any and all of your training questions. So if you want to check us out on Instagram, that's at empiricalcycling and weekend AMAs in the stories and sorry, my main feed is kind of boring, but we're working on that. If you want me to look at your FTP, tag me on Instagram and I'll look at your FTP and I'll probably repost it and Maybe I'll take a stab at what it is just based on your power curve. So with all that said, thank you all for listening and we will see you in the next episode. Bye everyone.