Essentials: How to Exercise for Strength Gains & Hormone Optimization | Dr. Duncan French

Welcome to Huberman Lab Essentials, where we revisit past episodes for the most potent and actionable science-based tools for mental health, physical health, and performance. I'm Andrew Huberman and I'm a professor of neurobiology and ophthalmology at Stanford School of Medicine. And now, my conversation with Dr. Duncan French. Duncan French, great to see you again. Likewise. Likewise. Thank you. We don't often have many Stanford professors in the Performance Institute, so I'm I'm I'm really excited. >> Well, this place is amazing and you have a huge role in making it what it is. I found dozens of papers on how weight training impacts hormones and your name is on all of them. What is it about engaging motor neurons under heavy loads sends a signal to the endocrine system, "Hey, release testosterone." I've never actually been able to find that in a textbook. Yeah, I mean, I think it's the stress response, right? It's mechanical stress and it's metabolic stress. And these, you know, the downstream regulation of of testosterone release at the gonads comes from many different areas. You know, the my work primarily looked at, you know, catecholamines and and and sympathetic arousal. So, things like epinephrine adrenaline. >> Correct. Yeah, epinephrine adrenaline, you know, and noradrenaline. How how they were signaling that signaling cascade using, you know, the HPA axis releasing cortisol and then, you know, looking at how that also influenced the adrenal medulla to release, you know, androgens and then signaling that at the gonads. There is is an interesting question. So, in presumably weight training in women, people who don't have testes, also it increases testosterone. And is that purely through the adrenals? When women lift weights, their adrenal glands release testosterone. >> Absolutely. I mean, that is the only area of of testosterone release for females. And yes, it's the same downstream cascade. Obviously, the extent to which it happens is is significantly less in females, but that's how you there's good good data out there that shows, you know, females can increase their anabolic environment, their internal anabolic milieu using resistance training as a stressor, and then they get the consequent muscle tissue growth, you know, whether it's tendon, ligament adaptations, you know, the the beneficial consequences of resistance training, which is driven by anabolic stimuli. Yeah, I have two questions about that. The first one is something that you mentioned, which is that the the androgens, the testosterone comes from the adrenals under resistance loads in women. Is the same true in men? I mean, we hear that the testes produce testosterone when we weight train, but do we know whether or not it's the adrenals or the testes in men that are increasing testosterone or both, a little bit from each? The field is divided presently in as much as understanding the acute the acute adrenergic response in terms of, you know, anabolic response to exercise in an acute phase and the exposure to you know, a stimulus that is stress-driven, which might be partly from the adrenal glands, partly from the gonads versus a longitudinal exposure to anabolic environments, which is primarily driven by obviously the gonads and the release of the endocrine environment from from testosterone release at the gonads. So, this the field is split in terms of how exercise is promoting hypertrophy, you know, muscle tissue growth, and whether that is very much an adrenal stimuli or if that's significant enough in these acute responses versus the longitudinal exposure just elevated basal levels of anabolic testosterone habitual levels. And then you mentioned that testosterone can have enhancing effects or growth effects on tendon and ligament also. That you don't often hear about that. People always think, you know, testosterone muscle, but testosterone has a lot of effects on other tissues that are important for performance, it sounds like. And what's the story there? >> I mean, the the testosterone hormone is it I mean, listen, there's androgen receptors on neural tissue, on neural axons. It's pretty much everywhere. >> Exactly. So, you know, it the the binding capacity of testosterone and influence in different tissues within the body. I touched on, you know, muscle tissue, but, you know, the the the ligaments, the tendons, and even bone to to some extent, you know, testosterone is is potential to influence that in in terms of removing muscle osteopenic characteristics, etc. So, yeah, it's it's a it's a a magic a magic hormone, let's say, with many many ends and impacts in terms of adaptation. Could you say that there's a there are some general principles of training that favor testosterone production in terms of that the that somebody who's not an elite athlete could use, who's trying to use weight training to build or maintain muscle, Yeah. lose body fat, so body recomposition, and or stay strong and healthy for sport of a different kind? Testosterone is really stimulated by an intensity factor, and also a volume factor. Now, growth hormone is a little bit different. That's largely driven by an intensity factor alone. If you look at many of the exercise interventions that we use to try and investigate and interrogate testosterone, it was it was usually, you know, a 6 by 10 protocol. So, six sets of 10 repetitions, which is, you know, it's quite a large, you know, 60 repetitions is quite a large volume for a a single exercise, and that was usually pitched at about 80% intense of a one repetition max intensity. Okay, so 80% of the one rep max, six six sets of 10 reps separated by rest of >> 2 minutes. 2 minutes, which is actually pretty fast, at least to me. And every time you see these 2 to 3 minutes, when you're actually watching the clock, those 2-minute rest periods go by pretty fast. >> By the third, fourth set, you're you're dying for more, yeah. Yeah. We formulated that kind of exercise protocol to really target, you know, the the release of testosterone and try and drive up these anabolic environments to study that, you know, the endocrine, um, you know, consequences. But, I think that's that's that's the type of protocol that is mo- most advantageous for driving anabolic environments. >> And that was it for the workout? Yeah, I mean, we we would do that in a back squat. So, you know, multi-joint, um, you know, challenging exercise, multi-muscle, multi-joint, 80% loads of of your one repetition max, and then 6 by 10. We did play around with, you know, your classic German volume type 10 by 10, um, kind of protocols. Um, but they were just unsustainable at that 80%. The The key to what we also did was we always adjusted, um, the loads to make sure that it was 10 repetitions that were sustained. So, if the load was too too high and an athlete or or a participant had to, uh, drop the weight on on the sixth repetition, we would unload the bar and make sure they completed the 10 repetitions. >> I see. Bringing me back to the point of it's an intensity and a volume derivative that that is going to be most advantageous for testosterone release. So, that sort of hints at the possibility that the thresholds for going from a workout that increases testosterone to a workout that diminishes testosterone is actually a pretty narrow margin. Yeah, and I think it comes back to that intensity factor then. You know, what what we saw with the that 10 by 10 protocol really sees pretty significant drop-offs in the load. Um, and again, we're trying to stimulate with intensity, with mechanical strain through intensity, as well as metabolic strain through volume. And I think that's that's the paradigm that you've got to look at is that the mechanical load has to come from, you know, the the vo- the actual weight on the bar, and the volume, um, is is the metabolic stimulus. How much are we driving lactate? How much are we driving, you know, glycogenolysis in in in terms of that type of energy system for, um, you know, executing a a 10 by 10 protocol. And what we often saw was just a significant reduction in the intensity capabilities of a of an athlete to sustain that. So, we shortened the volume um to try and maintain the intensity. Is there any evidence that training slowly can offset some of the negative effects of doing a lot of volume? The rest is often the consideration that's overlooked um out there in general population and in many sports and environments. You know, that the rest is is as important a programming variable as the load and the intense the intensity the load the the volume, etc. If you extend the the duration of your rest periods, what you're ultimately doing is influencing that metabolic stimulus again. You're allowing the flushing of the body, the removal of waste products, you know, lactate to be, you know, removed via from from the body and then the the metabolic environment is reduced. So, if I if I understand correctly, you want to create a metabolic stress. >> Absolutely. So, I could I could in theory do a 45- or 60-minute session where I pack in more more work per unit time. I'm not going to be able to quote-unquote perform as well. I won't be able to lift as much. I'm going to have to you know, unweight the bar between sets or maybe even during sets if I have someone who could do that. But, it sounds like that's the way to go. So, it's got to be So, this the old adage of high intensity short duration is probably the way to go. Correct. And and and you know, in in in layman's terms, if the same objective, the same training goal is just muscle tissue growth, and we're not talking about maximal strength or any of those type of parameters if you're just talking about growing muscle, if there's an athlete A and they do six six sets of 10 with 2 minutes rest, and there's athlete B that does six sets of 10 with 3 minutes left rest, athlete A will likely see the highest muscle gains because of the metabolic stimulus that they're driving with the shorter rest periods. What about day-to-day recovery? I mean, can Work out that you described as intense but short. How many days a week can the typical person do that and sustain progress? Yeah, I mean, I think that comes back to your training and your training history. Obviously, there's a resilience and a robustness with with an incremental training age. So, a protocol like that, we would look at two two times, you know, a week, something that's that's pretty intensive like that. Because again, it comes back to the point you make is that you really need to be for want of a better term, suffering a little bit through that type of protocol, both in terms of of the challenge of the load, but also being able to tolerate the the metabolic stress that you're exposed to. It's it's a it's a you know, a bit of a sicko feeling, right? Because of the lactate that you're driving up. So, you know, I wouldn't promote as an athlete doing that type of modality, you know, multiple multiple times unless you're from the realms of bodybuilding, and then you really that that's the sole purpose of of what you're trying to achieve. If it's just somebody, um, you know, a weekend warrior that wants to keep in shape and look and look good, I would say, you know, two times a week for a really challenging workout like that, and then flex the other types of workouts within the week to have more of a volume emphasis, where you reduce the intensity, and you might just look at, you know, larger rep ranges from 12 to 15 to 20. Another workout where you're looking at, you know, reducing the volume, but increasing the intensity, and really trying to drive, you know, a different stimulus to to give you more end points of of of success. Mhm. Last time I was uh here at the USC Performance Institute, we had a brief conversation, and I I want to make sure I got the details right, that in the short term, and a big increase in stress hormone can lead to an increase in testosterone. Like a like a parachute jump. >> Correct. >> Um, but uh so, stress can promote the release of testosterone. Yeah. That was news to me. Right. >> Um, we always hear about stress suppressing testosterone, stress suppressing the immune system, all these terrible things, but in the short term, you're saying it can actually increase the release of testosterone. Uh so, I have that right? Correct. >> Okay. And so, So the second question is does my cognitive interpretation of the stressor make a difference? In other words, if I voluntarily jump out of a plane with a parachute, does it have a different effect on my testosterone than if you shove me out of the plane against my will? Well, presumably with a parachute, too. I mean, so so this was what all my PhD work was was looking at was the you know, the pre the exposure to a stressor and the pre-arousal of how your body essentially prepares for that stressor and then how it manages it throughout the exposure to the stress. We used a resistance training protocol that that these athletes knew was going to be very very challenging. It's going to be there's going to have some anxiety to doing it. They knew there were going to be some physical distress from doing it. Um and therefore, you know, their their mindset of how they were going to approach that was already set. So what we saw prior 15 minutes prior to the the start of an ex-exposure to to the workout, that the epinephrine, the noradrenaline, the adrenaline was already starting to prepare the body sympathetically to go into what it knew was going to be a very very challenging workout. >> So what's the what was the takeaway there? Is it is the stress good for performance or is it harmful? >> That's a great question. From my data, certainly the the greater arousal, the higher the performance was from a from a physical exertion perspective. There's definitely a bio-an individual biokinetics to some of these hormonal kind of releases and as much as those guys that had the highest you know, adrenergic response in terms of epinephrine release, norepinephrine release, also sustained force output through for a longer period of the workout than those that didn't. So the the the individuals that had a lower stimulus of of the sympathetic arousal, let's say, certainly didn't perform as well throughout the workout. There's another side to this that I want to ask about which is the use of cold. In particular things like ice baths, cold showers. In theory that's stress also. It's epinephrine. And so um how should one think about the use of cold for recovery? You know, throwing your body into, you know, a cold tub, an ice bath, or whatever it may be, um certainly is going to have a physiological stress response. Now, people using that for different end end goals. And again, I think that's where the narrative has to be explained. Um if you are using that stress specifically to manage the mindset, um to use it as a specific stress stimulus, that's the same as me doing 6 by 10 80%. You know, you you're just trying to find something to disrupt the system to do something that's very um if you want a better term, painful, discomfort, whatever. Um you're just finding a stressor and then being able to manage the mindset. But if you're using cold um specifically from a physiological perspective to promote um you know, redistribution of vascularity of blood flow, you know, to to different vascular areas of of muscle that that you feel have gone through a workout, that are damaged, or whatever it may be. I think there's we we've got to understand what that stress mechanism is. Um and you know, the the data, the literature is certainly still out there with respect to cryotherapy and cold baths and some of these um you know, high these these cold exposures in terms of what they do at the at the level of the muscle tissue. If that's if that's the target, if you're trying to promote a flushing mechanism, or you're trying to promote redistribution of of the blood flow, what you've got to understand is that cold is going to clamp down every part of the vascular system. Um and we've really got to understand how the muscle would be redistributed um to areas of interest. So, you know, I think the stress response is is is is a real thing with respect to, you know, cold exposure. Um but I think the narrative around what are you using the cold for has to precede the conversation. >> Mhm. And cold, I've heard, can actually prevent some of the beneficial effects of training. That it can actually get in get in the way of muscle growth, etc. Yeah, there's there's there's some pretty robust data out there now showing that it it definitely has an influence on performance variables like strength and power in particular. Um but absolutely in terms of muscle hypertrophy. And there's a big kind of theme in in the world of athletic performance right now in terms of periodization of cold exposure as as a recovery modality. You know, what when do you use cold? You know, should you be using cold for recovery in periods of high training load when you're actually pursuing, you know, maybe general prepa- preparatory work, or you're actually trying to pursue muscle growth. Well, that's usually where you get the most sore. It's usually where, you know, you you feel the most fatigued, but it's probably not the most beneficial approach to use an ice bath in that in that scenario because you're dampening, you're dulling the you know, the mTOR pathway and and the the hyper- hypertrophic um signaling pathway. Whereas in a competition phase, where actually quality of exercise and quality of execution of skill and technical work has to be maintained, you want to throw the kitchen sink of recovery uh capabilities and recovery interventions in that scenario because you now you know, the the muscle building activity should be in the bank. That should have been done in the in the general prepa- preparatory work and um now you're focusing on technical execution. So, you're absolutely right. No, it's interesting. So, if I if I understand correctly, uh if if I want to maximize muscle growth or power it or, you know, improvements and adaptations, then the inflammation response to the late-onset muscle soreness, all this stuff that's uncomfortable and that we hear is so terrible is actually the stimulus for adaptation. And so, using cold in that situation might short circuit my progress. But, if I'm I, you know, I don't know that I'll ever do this, but if I were to do a an Ironman or something or run a marathon, under those conditions, I'm basically coming to the to the race, so to speak, with all the power and strength I'm going to have. And so, there reducing inflammation is good because it's going to allow me to perform more work, essentially. >> Absolutely. Yeah, you have to be strategic about when you use some of these interventions. And, you know, the the time when you're preparing for a competition is the appropriate time when you want to drive recovery and make sure that your body is optimized. Um, you know, when you're far away from a competition, you know, date or, you know, out of season or whatever it may be, and you're really trying to just tear up the body a little bit to allow it to to its natural, um, you know, healing and adaptation processes to take place, well, you don't want to negate that. You you know, you want the body to optimize its internal recovery, and that's how muscle growth is going to happen. So. So interesting. There there's a time kind of consideration that you need to make with these interventions, for sure. At the UFC Performance Center, are the are the fighters periodizing their cold exposure or are they just you doing cold cold at at at will? Well, it's not just the UFC, and again, I I I talk about my personal experiences with different sports. I think just education around where science is at and that our understanding of of concepts like the use of cold exposure for recovery, ice bath, you know, everyone wants to jump in an ice bath. But, I think as we've as we've stepped back and scientists have started to say have have started to figure out and look at some of the data, you know, we we're now more intuitive about, well, actually that might not be the best or the most optimal approach. And I think that's that's any given sport. So, yes, certainly here at the at the UFC, we're trying to educate our athletes around, you know, appropriate timing. And it's the same with nutrition, it's the same with an ice bath intervention, it's the same with lifting weights, it's the same with going for a run or working out on the bike, you know, the there's there's tactics to when when you do things and when you don't do things. And I think, you know, stress and and cold exposure, um we have to have a consideration around that as well, but it's not just, you know, MMA fighters, that's any any athlete. And I think it's the best the best professionals, the most successful professionals, do that really well. They unders- they listen, number one, they they educate themselves, and then they build structure. And I think, you know, at the most elite level, we we always talk about it here at the UFC, but the most elite level, you're not necessarily training harder than anybody else. Everybody in the UFC trains hard. Like everyone is training super hard. But the best athletes, the the true elite levels, are the ones that can do it again and again and again on a daily basis and sus- sustain a technical output for skill development. Therefore, their skills can improve or physical development, their physical attributes can improve. So, that ability to reproduce on a day-to-day basis falls into a recovery conversation. Now, when is the right time to use something like an ice bath and when isn't is part of the the high-performance com- conversation, for sure. For somebody that wants to get better at sport, uh do you recommend a particularly, um long or short training session? Does intensity matter, or is it just reps? No, it's it's not a volume-driven exercise, it's a quality-driven exercise. It is about rehearsal of accurate movement, accurate movement mechanics. Um and the soon as soon as that becomes impacted by fatigue or inaccurate movement, you're now losing the the the motor learning. You're losing the accuracy of the skill that, you You can call it muscle memory or whatever they want, right? But essentially you're grooving neural axons to to create movement patterns and they're situational throughout sport, right? You know, whether it's a Cruyff turn in soccer or a jump shot in basketball or a forehand down the line. You can carve out that particular posture and position and skill and you can isolate it and you can drill it again and again and again. Now, as soon as fatigue is is influencing that repetition, it's time it's time to stop. And the best coaches understand that. It's shorter sessions that are very high quality and I think the best athletes in my experience are the ones that consciously and cognitively are aware of it at every moment of the training session. A 3-hour session versus a 90-minute session, you know, we'll we'll take the 90-minute session any day when it comes to skill acquisition because that's going to be driven by quality over quantity. Yeah, training and skill learning is incredibly mentally fatiguing. You hit a really hard workout or run early in the day. What leads to the mental fatigue after physical performance? If you have an amazing coach who is setting up training in a particular way, it's challenging. It there's a strain related to it and I'm not talking physical strain, I'm talking figuring things out, you know, figuring out the skill and I think that can be stressful. Like, you know, if they if they hit the right technique, you know, that reward center in the brain, that dopamine shot is is going to fly up there and there's only so many times that we can get that before that becomes dampened. And I think there's an energetic piece to it, you know, there's the fueling of of the brain. There's the there's the the the carbohydrate fueling exercise that actually the strategy around how you fuel for learning and fuel for physical training is is actually pretty similar. Yeah, it's it's glucose. It's sugar at the end of the day, right? Do you think that um nutrition that doesn't include a lot of glucose, doesn't include a lot of carbohydrates, um is a problem. Yeah, again, disclaimer, I'm not a dietitian. Um but I I I I I think for it's it comes down to metabolic efficiency. You know, we rarely advocate a high-performance athlete in a in a high-intensity intermittent sport like MMA being totally ketogenic. Because at the end of the day, some of those high-intensity efforts um usually require, you know, carbohydrate fueling um for for the high and at the energy um the energy produced at those high intensities. >> Can I interrupt you real quick? What about ketones for people that are ingesting carbohydrates? This is an interesting area because people always hear ketones and they think, "Oh, I have to be ketogenic to benefit from taking ketones." Right. >> But there are a number of athletes and um recreational athletes now as well taking liquid or powder-based ketones on even though they do eat rice and oatmeal and bread and other things. As So, w- are there any um known benefits of ketones even if one is not in a state of ketosis? The use of ketones that I'm primarily aware of is is um in our sport is after the event, you know, in terms of the brain health with with athletes that take, you know, potentially taking trauma to the brain, etc. and looking to maintain the the the fueling and the energy supply to the brain. But yes, it's probably a little bit out of my remit. So, I I don't want to talk on that because I'm not I'm not fully familiar with that. Um to come back to your original question, if it's a you know, general population, then yes, I think there's there's a place to argue that actually being on a ketogenic diet at times and maybe that's to cycling exercise, maybe not, I don't mean cycling a bike, I mean cycling um ketosis um is beneficial because I think it's going to lead to better metabolic management and and and better metabolic efficiency at those lower intensities where we should be fueling our our metabolism with lipids and fats. Um clearly the the Western diet and and you know, the modern day diet is heavily driven by processed food and carbohydrates that, you know, people become predisposed to utilization of that fuel source above lipid use, fat use at intensities that are very low. So, you know, some of our data with the fighters shows that as well. But, I think the challenge for us is that we're working with a clientele that require high intensity bouts of effort. So, you know, fueling appropriately is very important for that. Now, we use we use tactics here where we essentially have athletes on what you would say kind of a is it a largely a ketogenic diet, but then we will fuel carbohydrates around training sessions. So, we'll do very timed exposure to carbohydrates. So, it's not post training, post training, immediately pre during and then immediately post. And then the rest of their diets, you know, breakfast, lunch, and dinner what would look like ketogenic type approaches. So, we're trying to be very tactical in the exposure to maximize the intensity for the training and then return to a metabolically efficient diet which is heavily reduced in carbohydrate because we've fueled the sessions that needed it. The way I understand metabolic efficiency is that you you teach the body to use fats by maybe doing long long bouts of cardio, maybe lowering carbohydrates a bit, so teaching the body to tap into its fat stores for certain periods of training. And then you also teach the body to utilize carbohydrates by supplying carbohydrates immediately after training and before training. You teach the body to use ketones and then you use them at the appropriate time as opposed to just deciding that one of these fuel sources is good and all the others are bad or dispensable. Do I have that correct? >> Yes, you're absolutely right. I mean, at low intensities of exercise or just day-to-day living, we shouldn't be tapping into our carbohydrate fuel sources extensively. That that's that's for higher intensity work or, you know, the fight or flight needs of of stress, you know? Um if, you know, athletes or any individual has a, you know, a high carbohydrate diet, they're going to start to become predisposed to utilizing that fuel source preferentially. Now, at low intensity, that can be problematic, certainly for an athlete because if they preferentially use carbohydrate at lower intensities, when the when the exercise demand goes to a higher intensity, they've already exhausted their fuel stores, you know? They can't draw upon fat because the oxidation of that that fat is just too slow. So, they're essentially now become fatigued um because of they've already utilized the carbohydrate stores. So, what we try to do, yes, through diet manipulation and a little bit of exercise manipulation is, as you say, teach the body or train the body to preferentially use a specific fuel source, fat obviously at lower intensities and carbohydrate at high intensities. And we look at specifically the crossover point between the two tells a lot in terms of how an athlete is is ultimately um yeah, how their metabolism is working. I think most people are looking for that one pattern of eating, that one pattern of exercising that's going to be best for them or sustain them, and they often look back to the time when they felt so much better switching from one thing to the next, but the adaptation process itself is also key, right? Teaching the body. And I um so, if we were to um just riff on this just a little bit further, if somebody is eating in a particular way and they want to try this kind of periodization of nutrition, um could one say, "Okay, for a few weeks I'm going to do more high-intensity interval training and weight training, and I'm going to eat a bit more carbohydrate cuz I'm depleting more glycogen. Then if I switch to a uh phase of my training where I'm doing some longer runs, maybe I'm not maybe I'm training less, maybe I'm just working at my desk a little bit more, then I might switch to a low lower carbohydrate diet. Do I have that right? And then if I'm going to enter a competition of some sort, certainly not UFC right? Or MMA of any kind to be clear. Not because it isn't a wonderful sport, but because it's that wouldn't be good for my other profession. But if I were going to do that, then I would think about stacking carbohydrates, ketones and and fats. Is that do I have that more or less right? >> I think yeah, you just said it eloquently. At the end of the day, you're consciously understanding what the the exposure to to physical exertion is and you're flexing your diet accordingly. A couple more questions. I I can't help myself. I know we talked about temperature earlier. I have to ask you about heat. One of the reasons to a deliberate expose oneself to heat is for things like growth hormone release, etc. We talk about this, but how does one get better at heat adaptation or at least what are you doing with the fighters to get them better at dealing with heat? Barring like hyperthermia and death. Like I mean obviously heat up the brain too much, people will have seizures and die. But you lose neurons. But what's the right way to acclimate heat? Yeah, so we we we normally start with about 15 minutes of exposure. Now if someone's really lacking acclimation to heat, you know, you can do that in three five minute efforts. Do you know what I mean? And actually take time. >> hot sauna. Yeah, hot sauna. Take time to step out. >> 200 degrees or something. >> Correct. Yeah. 200 Fahrenheit, yes. And we we we try to work up to 30 to 40 minutes to 45 minutes in the sauna continuous. Now we we have to understand, you know, what what's the advantage of heat acclimation for our athletes? Ultimately, their ability to sweat and to lose, you know, body fluids is going to be advantageous to their weight cut process. So their ability to make weight. It is a technique that these guys some of these guys adopt. So if you don't have, you know, a high sweat rate, it means you're going going to sit in the sauna for longer and longer and longer to get the same delta in sweat release. Um so, the more acclimated you are, the more your body is thermogenically adapted, the more sweat glands you have. So, you know, we start with 15 minutes and then we just try to add on and add on across a time. And now now for us we kind of found about 14 um sauna exposures starts to really then drive the adaptations that we're looking for. So, it's not a quick fix. You know, a a heat acclimation strategy has to happen long before fight week or long before the fights. You know, this is a this is a process that has to begin, you know, 8 to 10 weeks before the fight so that we can actually get that adaptation and that tolerance to the stressor to the exposure of heat. That's interesting. I until today, when we talked about this earlier and again now, I didn't realize that um but it makes perfect sense now that I hear it that heat adaptation is possible. That you basically can train the body to become better at cooling itself, which is what what sweating is. The body is a you know, as an organism, as an organic system, it's it's hugely adaptable. It's hugely plastic, but I think the skill is understanding the whens, the whys, and the whereofs in terms of changing the overload, changing the stimulus to drive specific adaptation. And philosophically that's that's how we go about our work here. We talk about adaptation-led programming. Now, adaptation-led programming fits into every single category, not just lifting weights or running track. It fits into nutrition. It fits into sitting in the sauna. It fits into being in a cold bath or not. It fits into so many different things because we're driven by scientific insights. And and that's how we really want to go about our business. If someone wanted to experiment with heat adaptation or experiment with cold adaptation or change up their training regimen or or diet and look at metabolic efficiency, do you think 12 weeks is a good period of time to really give something a thorough go and get get gain an understanding of how well or how poorly something works for oneself or would you say eight is enough for three? For 99% of things that change within the body that physiologically adapt to a training stimulus or an overload stimulus, you're going to start to see either regression or progression, you know, beneficial or detrimental effects within three months. Absolutely, I would say. And I think, you know, the individual interpretation is always has to be considered. And I think that's where it comes back to to be a thinking man's athlete or be a thinking man's trainer. Like someone that's going through exercise. Don't you have to cogni- consciously understand where your body's at any moment in time. You know, you've got to be real with yourself. You create a journal, create a log of your training, create a log of your feelings, your subjective feedback of you know, how you felt, your mood, your sleep. >> athletes do that? >> Yeah. Yeah, we we we try to promote that because again, that's that's part of this this process, you know. Um Maybe 12 weeks for you, but I might get the same responses in eight eight weeks, you know. We could put 15 guys on the mat and give them the same workout and there's going to be 15 different responses to that same workout because the human organism is so complex and innate that it's going to adapt differently. You know, some people will tolerate it, some people are going to be challenged by it. Some people have got a metabolic makeup that's going to promote it, some people are meta- metabolically challenged by it, you know, there's there's just so many different things that we have to consider and that's what we try to do here. It's the cross we bear is that we try to understand on an individual level how to optimize athletic performance. Duncan, when you speak, I learn so much. I I'm going to take the protocols that I've I've heard about today. I'm going to think about how I'm training and how I could train differently and better, how I'm eating, how I could eat different differently and better for sake of performance and just in in general. Um Thank you so much for your time your scientific expertise the stuff you're doing in the practical realm it's it's immense so hopefully we can do it again. Yes thank you this has been a blast I appreciate it and yeah keep doing what you're doing cuz I know there's a lot of people out there that love the platform so thanks for the invite it's been awesome. Thank you thanks so much all right.