Should You Train At Loads That Maximize Power & Why You Won't Improve Central Adaptations w/ Zone 2 (SSOF Ep 106)

James de Lacey0:00

But essentially you're just doing escalating loads, doing a few reps at each load, and you're finding the load which, which peak power or mean power is maximized during that lift. And the idea is that training at the load that elicits the greatest power output means that you should in theory increase power output more than if you weren't training at that load. And there are a couple of schools of thought around that, so I'll kind of debate club myself on that one too.

But typically for ballistic style movements like jumps and throws, anywhere from 0 to 30% of one rep max is typically where it's typically optimal power load. And when we're talking about one rep max in these instances, so for example a jump squat is usually based on one rep max of the back squat, and a bench throw is usually based off the one rep max of the bench press.

For more full body exercises like power cleans, it's usually above 70% one rep max, and that one is based off the power clean. So if you can power clean 100 kilos, it's usually above 70 kilos in that instance.

Now there's a lot of research by pretty much honestly the same researchers around this. I think Loturco out of Brazil, he must have done his PhD on this topic, and he had access to a lot of national, even elite level athletes to test on. So I want to run through some of the research.

And the first thing we're going to look at is comparing elite versus non-elite athletes. And I really like this as a way to decipher whether something is useful or not. I talk about that a lot within agility research or just agility training, where people often think running between cones, going through ladders, touching flashing lights is agility training, which it is not. It is just general random reaction, slash change of direction training. Which when you compare elite and sub-elite athletes, they tend to have similar scores or similar results, or the sub-elite athletes can potentially do better.

But when you have a sport specific stimulus to react to, the elite athletes far outperform the sub-elite athletes, which shows that that quality is very important for success of that sport. Now we're going to do the same thing with optimal power load. Essentially, are elite athletes able to produce more power at heavier loads than sub-elite athletes?

Loturco and his colleagues in 2018, one of his authors on his papers is Dr. Mike McGuigan. He was one of my academic supervisors during my Masters. He's probably one of the OG power researchers. If you just search Mike McGuigan on Google Scholar, you'll find he's got a billion papers on power development.

But anyway, they took 330 elite athletes. This was from soccer, handball, rugby, and football. Now this isn't comparing elite and sub-elite, but this is just a good place to start. What they did is they measured power output in the jump squat and half squat, and they saw that rugby players had superior average and peak power output than the other three sports. And I think that's important, just hold on to that because I'm going to come back to that as well. I like that one because it kind of shows based on the sport the requirements that are needed to be successful.

We then have a paper in 2020 by Loturco again and his colleagues. They showed that sprinters display greater force velocity power, jump and jump squat height than rugby and soccer across all loads. So essentially sprinters are just way more powerful. They also displayed optimal power load at greater relative loads, and we're talking 22 to 26% higher.

So essentially by greater relative loads, it means at higher body mass percentages. So for example, I think in that study they maximized at 80% of body mass. Can't remember what the other two sports maximized at, but essentially they're able to maximize power output at heavier loads relative to their body weight. Which means that technically loads under that, they should be able to produce more power as well, as shown by having higher force velocity power across all loads.

If we go directly into combat sports, we see that again Loturco and his colleagues in 2017 they took a number one ranked WKF karateica, and he was a two-time world champion at the time. And all his papers he uses the same tests, so in fact I think every optimal power load paper, or pretty much every single one, uses the same test of jump squat and bench press or bench throw or half squat. That's kind of like the same.

But essentially he was able to generate 45% greater mean propulsive power, so just essentially accelerating through that concentric action in the jump squat, and 7% greater in the bench press compared to other national team athletes. So this guy was number one, two-time world champion, 45% greater mean propulsive power in the jump squat, which is huge, compared to other national team athletes.

We then have a paper from Pereira and his colleagues in 2018. They took 28 elite female handball players. And that essentially it was half of them were from the Brazilian national team, and then the other half were essentially college players. So college players weren't elite, but essentially it was elite versus non-elite because you're going national team versus college. They used the same jump squat, bench press, and then they had physical performance tests too.

They found that the Olympic athletes, which were the national team athletes, jumped higher, produced more relative power in the jump squat and bench throw at optimal power load. So essentially more powerful. So that covers pretty much all the research on the elite versus non-elite. So we can see that high level athletes tend to either display more power at optimal power load or able to produce more power at heavier loads, which can translate into potentially better performance, which we're going to cover now.

So optimal power load, how does it correlate with sports performance? And there's a couple of good papers. The same one from Loturco, the one with the 330 elite athletes that I mentioned before, soccer, handball, rugby, football. And they stated that the bar power outputs, so we're talking about the mean power, peak power, etc., were more connected to better performances in speed and power assessments.

So essentially, not half squats, so essentially barbell, the power generated through jump squats and the bench press were more associated, or more, I'm not going to say causal, it's not causal, but better associated or more likely to predict jump, sprint, and change of direction performance than how heavy you can lift in the half squat, which would be a maximal strength measure. So essentially barbell power output more predictive of those more explosive sporting actions.

We also have two studies by Loturco again. He's just been on a tear on this. Elite karate and elite amateur boxers, so this will be Brazilian national team karateica and boxing athletes that shows strong correlations between power output during the jump squat and punch impact force and punch acceleration.

So essentially the boxers and karateica that could display higher power outputs during the jump squat, and typically that would mean jumping higher with it as well, they were able to essentially punch harder in this instance. I'm going to cover one more thing and then I'm

Going to kind of sum it up what this all means and what my thoughts about it all. Then kind of doesn't even matter. We can then go to optimal power load training. So often when we talk about optimal power load, we're talking about training at optimal power load. Does it really matter?

Wilson and his colleagues in 1993, they found that jump squats at optimal power load led to greater jump performance and six-second cycle sprints than plyometric only, so our very velocity dominant exercise, or heavy squatting only, which would be our heavy strength training exercises. So training in that middle zone tended to transfer better to jump and sprint cycling.

Lacko and his colleagues in 2018, they took 12 elite amateur boxers from the Brazilian national team. So in this there were, you know, one Olympic champion, one Olympic bronze medalist, three Pan-American Games medalists, and all athletes were South American Games medalists. So a very high level cohort of boxers. And they went through 14 power-orientated training sessions of the bench press and jump squat with the optimal power load. And this was for the preparation for the 2016 Rio Olympic Games. And this was done, I think it was six sets of six for each exercise.

The period they had before that was served as the control. So this was the intervention period. So all the athletes went through the intervention of the 14 power sessions over, I think it was seven weeks. And then the control period was the period beforehand, I think it was lead up to another event that wasn't the Olympics, where they were still doing strength and power sessions, but they weren't controlled. So it was just kind of what they were already doing. Now what they consisted of, I do not know, but it wasn't geared towards optimal power load training.

Now what they did is they measured power on the jump squat and bench press before and after the seven weeks of those six by six. And they found that the optimal power load training intervention led to greater power outputs after that seven weeks compared to the control intervention before and after, if that hopefully that makes sense. So essentially control before and after, they had a slight increase in power output at optimal power load. But after the optimal power load training, they had the greater increase.

Now obviously you could say, well, they trained optimal power load so they're kind of used to jumping and performing movements at that loads. You expect it to increase versus the control. They didn't really, potentially didn't emphasize optimal power load, so there's a lot to take in there too.

We then have, again, Lacko in 2016 and his colleagues, they did two six-week train blocks. So they essentially split them in half and they had a traditional strength power periodization block, so six-week block, and that was like a block periodization, I guess, setup. And that was like strength endurance, must have been for two weeks, two weeks, two weeks. So strength endurance for two weeks, maximum strength, and then power.

And then the optimal power load training group, they essentially did four weeks of half squats, so I guess heavy strength, and then two weeks of jump squats, which would be like their power stuff. And this was in elite soccer players. They found both groups achieve similar strength and jump performance, but only the optimal power load group exhibited greater increases in sprint speed and jump squat power. So potentially better transfer doing that versus going through a traditional block periodization approach where you're going from strength endurance to max strength to power in that six weeks in that cohort, in that example.

Which brings me to what does this all mean. Now the question becomes, do we go down the traditional strength and power training route, or just throw it all away and train at optimal power load as much as possible? Based on the research that we've just gone through, it seems optimal power load training could potentially be superior than a, say, traditional training program, especially since optimal power load is highly correlated with sporting actions, meaning it's predictive of, again, jump performance, sprint performance, etc.

But in my opinion, I don't believe we should only train at optimal power load and we shouldn't throw everything away just based on this research. And I think the biggest thing is we're comparing doing one thing versus doing another one thing, where a training program should not just have one thing. We should not just be targeting, just be doing heavy lifting, just be doing optimal power load, just be doing velocity style training. We should have a mix of it, and it should typically depend on the sport itself. And I'll touch on that in a second.

Secondly, is it training at optimal power load that causes elite athletes to show greater power at heavier loads, or is it a product of their training covering the entire force-velocity relationship and likely emphasizing the extreme ends? It's a question because we can't say it's causal. We can't say that elite athletes display greater power outputs or are able to jump higher with heavier loads because they train optimal power, because they potentially haven't for most of their career.

And it could be that genetic factors come into play, training age, how they trained, all these things play a role, including their sport training volume on top of that as well.

And when I talk about the force-velocity relationship, essentially we're talking about the inverse relationship between force and velocity. And the inverse relationship means high forces come with low velocity, and high velocities come with low forces. And you have this inverse relationship that as speed increases, force decreases, and vice versa. So I'm going to touch on that. Oh, actually, I'll touch on that now anyway.

But essentially, when we're talking about emphasizing the extreme ends of force and velocity, it's because of this relationship where power is a product of these two variables. So force times velocity equals power. So if you're able to improve force production and or improve velocity, you're enhancing power output based on that physics equation.

Now, many coaches have this philosophy of emphasizing the extreme ends. I think on the Sweet Science podcast, if you listen to Travis McMaster with the New Zealand All Blacks Sevens, he follows that philosophy. I don't think he is a big fan at all of training in this middle spectrum for the idea where we want to maximize the force side, we want to maximize the velocity side, they should come together and then give us more power.

And the whole premise behind that is that if you're training at loads that maximize power output, it means you're also training at loads that are submaximal in force and submaximal in velocity. That becomes the theoretical downside of training at these loads. You're not maximizing speed, you're not maximizing force output. So what are you really training? You're kind of just training power. Is power that, I guess, influential and important when we need to kind of touch on either end?

So some coaches prefer to train just, you know, get really strong, maximize force during strength training movements, and maximize velocity through plyometrics, jumps, throws, etc. But I don't think you should just neglect the middle of this relationship. There's a really good example of paper by Toji and Kano in 2004, and they found that training across the force-velocity relationship results in greater maximal power than training heavy and light.

So into training just pure velocity-based plyometric jumps at probably assisted or body weight and then training very heavy squats, bench presses, etc., was less effective at improving maximum power than kind of surfing the curve, as they call it in there.

And when I'm talking about the middle part of the force-velocity relationship, we're talking about various loads, and I'll kind of run you through the spectrum now. So you kind of got the very far velocity speed in there. Typically assisted reps or less than body weight, and it's very hard to do less than body weight in a lot of traditional exercises.

So typically one way of doing that was actually doing like a band-assisted jump. Tie a band to like a pull-up bar, wrap around you like a backpack or hold it, and then jump. And ideally that was decreasing body weight. New research has come out to show that potentially is not happening.

The other way is doing like band-assisted sprinting. If, I mean, if sprinting is body, a sport, but we're combat athletes, so probably not. But band-assisted sprinting as an example, downhill sprinting or running, so that way you're getting overspeed. And then another good way is lying on your back, say like on a skateboard, and then pushing off a wall. You're removing body weight, and that becomes a pure velocity-based exercise. So that's like the very velocity end.

Then you've got body weight, so going against gravity essentially with body weight. So your typical jumps, box jump, plyometric exercises, tuck jumps, pogos, hurdle hops, drop jumps, step jumps, all that kind of stuff falls on that spectrum. Then you've got your very lightly loaded exercises. This could be like medicine ball throws of various loads. You could also throw lightly loaded jumps. So I like to often use 10% of body weight as like a very lightly loaded jump. You can hold that with dumbbells. That would be like your spectrum of velocity-based exercises from unassisted or less body weight, body weight, and then slightly above body weight.

And then you get into this maximal power, optimal power, I guess zone, where you're doing things like jump squats, bench throws, etc. And you're using 20 to 45% one rep max, depending on where that kind of sits. And we'll touch on that in a bit. And that's where you're kind of doing moderately loaded ballistic actions.

And then you go to the next step above that, you have slightly heavier power-based exercises, and that's typically done through Olympic lifts or Olympic weightlifting derivatives. So that's things like power cleans, clean pulls, hang cleans, hang high pulls, snatch pulls, snatch high pulls, power snatches, all that kind of stuff falls into that spectrum, depending...

On how you're loading it, you can also throw kettlebell swings in there. That will kind of go between the ranges if you don't want to do Olympic lifts as an example. And that's where that would fit there. And then above that then you've got your traditional heavy strength training exercises, right? Squats, bench rest, deadlift, etc. And that's kind of the spectrum of the force-velocity relationship and how you can kind of touch on, I guess, the entire relationship within a training program.

That tends to typically be the method most coaches use. I think it's a wise way to do things. You're not going to do equal amounts of volume across the whole force-velocity relationship. That doesn't make any sense. It's just too much work. Typically I like to lean more toward one end or the other depending on the combat sport.

Before I go down that road, I have one more point to make. That just avoiding a certain part of the force-velocity relationship for whatever reason, I don't think is a good idea. Because we need to understand that the strength is also specific to the loads being lifted. So the adaptations we're gaining at certain loads, well, the adaptations we're gaining is specific to the load.

For example, there's a reason, a very easy example to, I guess, think about this and understand it, is you spend 6 weeks doing 20 rep squats. So that, if anyone's familiar, Super Squats, a 20 rep squat program, well-known for packing some mass on your legs, but your one rep max will not go up. And the reason is the adaptation gained from doing 20 rep squats does not transfer to this one rep max strength.

Strength is specific to the loads being lifted. You need to lift heavy to be able to improve one rep max strength because one, the lift itself is a skill, and two, the adaptations you gain are specific to the loads being lifted.

Which is why typically you want to trend across the spectrum, because you want to have those adaptations occur. So for combat sports, where you're throwing other humans around, you probably want to perform exercises where you're throwing loads or performing heavier weightlifting derivatives or jumps, because that is what you're going to be doing within the sport. So grapplers and MMA I believe should probably spend more time in that kind of optimal power load zone versus strikers which can spend a little less time there.

And that typically means that, I'll mention this in a few videos before, but across the spectrum, striking falls more on the velocity side, MMA more in the middle, grappling more on the force dominant side. So training should kind of reflect that, which means that for grapplers you're going to spend more time doing just heavy basic hypertrophy work. You can spend a lot of time in that optimal power load or heavier strength, I guess heavier power sizes.

So that would be like your jump squats at 20 to 40% one rep max, your bench throws. That would be Olympic weightlifting derivatives, kettlebell swings, all that kind of stuff. You're still going to do some of the velocity-based movements at the plyometrics and bodyweight jumps, but just going to make up less of the total program.

For MMA, you might have a more even spread across that force-velocity relationship. You might have quite a bit of velocity-based movement. You might have a little bit of the middle where you do optimal power load work, weightlifting derivatives, etc. You might have a little bit of the heavier maximal strength side.

For strikers, you might spend more time on the velocity end. So you might have a lot of the less than bodyweight and bodyweight style plyometric jump training, a little bit of the throws and lightly loaded jumps. You might do a bit of the stuff in the middle where you may be doing some loaded jumps. You don't, I don't think you need to do any kind of weightlifting derivatives in this instance. You can if you're comfortable doing them and you're doing a little bit of max strength work as well.

And that kind of, if you have that in your head, it makes creating programs or at least having a philosophy around your training a little easier to put together. Now, how do you know what the hell optimal power load is? So you need equipment or a phone app and time.

In terms of equipment, you're looking at accelerometers or linear position transducers. So brands, GymAware is probably the gold standard when it comes to linear position transducers. What all that does, connects to the bar, measures force, velocity, power, etc. So that's something you can do if you're kind of wanting to go all in.

There are cheaper models of stuff that you can kind of just connect to the bar. Push Band was one of the original ones, but they've been bought out by Whoop. Do not touch Whoop with any, with a 10-foot pole. Whoop is the most inaccurate tracker for anything. But Vmaxpro is another one. There's a few different velocity trackers. And a lot of them are, you know, a couple hundred bucks, and they have phone apps that can do that stuff for you.

Another way to do it is do a phone app that will cost you $17 called My Jump Lab. I use it often, My Jump 3, but they have one called My Lift, and it's velocity-based training through your camera. And essentially you record your lift and you choose start and end points and loads, and it will give you the velocity of your lift and it will give you power outputs based on the load as well.

So you're then, you can do your, for example, if you're doing say bench press, you would just do your different loads and I'll jump, I'll go through that in a sec. You analyze each video in the app and you'll see the increasing power, then the decreasing power, and that will be your optimal power load.

So for doing the test, if you do decide you want to do the test, you start with 40% of body mass for lower body and 30% of body mass for upper body. So for jump squat, 40% body mass; for bench throw or bench press, 30% of upper body, 30% of body mass. You increase each set by 10% for lower body and 5% for upper body. And you're just going to go essentially until, honestly until probably around 100% body mass, and that should be enough to get you unless you're an absolute freak powerhouse. Then you might go up to 120% body mass.

But essentially you're going 40% body mass, 50, 60, 70, 80. You're going to do three reps, two to three reps at each. If you just do one, you're going to have too much variation. So two to three reps, typically three reps at each load, have plenty of rest between. And then that'll give you optimal power load.

If you don't want to go through all that rigmarole and get the devices and everything else, some general rules. So typically, based on the meta-analyses we have now, 0 to 30% one rep max for jump squats and bench throws is typically where it lies. So you can kind of vary between that range if you want. So for example, you can kind of cycle, you could go like week one, 10% one rep max, 20% one rep max, 30% one rep max for week two.

I've seen jump squats even go up to 40, 45% for optimal power load in some populations. So you may even spend a little bit of time above that too for jumps. But you can kind of cycle that around depending on what you're trying to achieve from that. If you want to go more velocity-based, you can go a little lighter. If you want to go a little, I guess, more heavier-based, you can just go at like 40% as an example.

Bench throws, you would do in a Smith machine, ideally, that way you don't chop your head off in case you missed catching the bar. And then obviously if you're doing it for Olympic lifts, above 70%, typically it's 70 to 80 or 85% one rep max off your power clean maxes for optimal power load there.

And I think with Olympic lifting, it's almost inherent when you're doing them that if you go kind of as heavy as your technique allows with really good snap and speed, you'll kind of get there anyway. So that would be kind of training that very middle for optimal power load or loads that maximize power output.

Again, you don't have to spend all your time there. Just because you're training there does not mean you're going to become an elite athlete. Just because an elite athlete displays the most power or lifts the most weight at those loads does not mean the reason they're an elite athlete is because they do that. Again, it's just correlation.

Actually have a question here live in the chat. So he says, "I'm way out of shape right now. Real life. Do, okay, right now do, I can't train kickboxing which should be possible after the summer. Oh, right now, real life, man, I can't keep up with all these acronyms, what should be possible the summer. I can however do S&C, 60-minute biking, Zone 2 work and some kiddar work."

I'm assuming there's a question coming after that, but regardless, yes, do your S&C work if you can do it. If you're injured, why right now and can't train kickboxing? Okay, well, depends why you can't train kickboxing. I'm assuming it might be a time thing. Or how should you set that up? Yeah, you can set that up. Honestly, it depends if you're a competitive kickboxer or not. I don't think it's going to matter so much, and depends on your work-life schedule. But easiest way to do it is just alternate lifting days with conditioning days. That way you...

Get three lifting days, you get three conditioning days, super simple. You can do one or two days of lower intensity, amateur looking for a first fight. Yeah, okay, so you can go one or two days lower intensity and one day higher intensity. The following week you could even do two higher intensity, one lower intensity and kind of alternate that.

For your lifting, looks like you got kettlebell work. I don't know if you have barbells, dumbbells, etc., but you're just going to set up your strength training by, like we just talked about, now I'm kind of covering that force-velocity relationship. So you're going to start your sessions with some form of jumps, plyometrics, throws, maybe do your kettlebell swings or kettlebell snatches, something that's loaded and fast.

And then you can finish with something that's slightly heavy. If you only have kettlebells, it might be like a double front rack kettlebell rack front squat kind of thing, could be farmer's walks if you have kettlebells heavy enough, things like that.

So basically you're going to go from your fastest exercises through to your loaded power-style stuff through to your heaviest exercises, session done. Following day, do your conditioning. Following day, back to your strength work. Make sure you mix up some of your movement patterns, so if you're doing say a squatting-style variation on the first day, to a deadlifting-style variation on the second day, then for the final day you can do like a single-leg variation.

Same with upper body. If you're doing like horizontal pressing on Monday, then on Wednesday do some kind of vertical pressing or incline pressing kind of thing. So just mix it up and you won't have any issues there.

Just something basic like that will get you going. Well, you mentioned obviously biking zone two, 60 minutes biking zone two. Sure, that's definitely worth doing. I'm actually going to touch on that right now because we had, I had some good feedback on my MMA conditioning video I did. Please go check that out on the Sweet Science of Fighting YouTube channel. Show me some love there. It's slowly spreading. Had so many good comments on there, people saying this will eventually blow up, but obviously the YouTube guards are not with me right now. So please go check that out.

But essentially I was talking about the central adaptations to zone two. Now I've got this book, it's showing on the screen if you're watching this on video. It's called Endurance Training. It's an old, old book and I just pulled that out of the bookshelf the other day. I've read it before and I had some notes in it, and I was just kind of skimming through it and I saw this passage here and I thought that this kind of sums up what I was saying around zone two and the central adaptations that you're going to get from, and something that I've kind of been looking at and wrestling with and stuff I want to ask some more highly knowledgeable physiologists about soon on the podcast.

But we, I talked about a lot about prioritizing peripheral adaptations in the muscle. Oh nice, he says it's good content though, listening to the podcast on Spotify at the moment. Well thank you very much, I appreciate that. Well, the Sweet Science of Fighting channel, I said that so wrong because I supposed to be like hard or something like that, sounds more Dutch than how I said it. But the Sweet Science of Fighting YouTube channel is YouTube videos, not podcast, so I kind of try to edit those so they're more engaging and things like that. So check that out.

But we talked about peripheral adaptation being the most, potentially the most important to combat sports. Now the reason zone two might not be the best way to go about it, I mean for long, I mean you got longevity podcasts and stuff talking about zone two, this zone two that, VO2 max this, that, etc., but I don't give a [expletive] about that. We only care about maximizing combat sports performance.

Athlete's heart adaptation is dependent on total volume of training and sensitive load and years of training experience. If the volume of training is less than 6 hours weekly, morphological adaptation of the heart is unlikely. With 10 to 15 hours weekly, competitive athletes achieve a small degree of athlete's heart adaptations. Now when we're talking about large volumes of training that triathletes and cyclists undertake, who have the largest hearts, they have many years of intensive training with volumes of 25 to 35 training hours per week which are necessary to achieve this.

So when we're talking about central adaptations, okay, I'm going to go hit the roads twice a week, five miles. Okay, what, I shouldn't use imperial system. Let's just say 10K runs, which is still quite, 5K runs. 5K runs, then you're doing, let's just say you're doing zone two at that, which would probably be like 30-ish minutes, say two, even three times a week. That's an hour and a half. Then you say you're training your combat sport four times a week for an hour. So now you're at 5.5 hours. Let's just say 6 for the sake of it.

So training volume less than 6 hours is less likely to create these central adaptations that you want. You need 10 to 15 hours weekly over long term to see small degree of heart adaptation, which means that you would have to increase, even if you're training your combat sport, let's just say you're training 6 days a week for an hour, some sessions maybe 2 hours, so let's say you're getting 8 to 10 hours just from the combat sport, you would have to add another, well if you're doing 10 hours you'd have to add a little bit more, but not all of it's going to be in this low-intensity zone.

But you're still going to have to add at least an hour of zone two on top of your six combat sports sessions and on top of your strength training sessions to see these small changes in central adaptations.

And then you want to make more gains, you're going to have to continue increasing the volume of that, above 15 hours a week, which then becomes a logistical nightmare for your actual combat sport technical training. So that's, I think that's something to be aware of when we're talking about central adaptations and zone two. I had another page in here as well on this.

So typically we're talking about, when we're talking about intensities of conditioning, we're typically referring to substrate utilization, meaning what are we using for fuel. And our two fuel sources, our two main fuel sources, are fat and carbohydrates. The more intense exercise becomes, the more carbohydrates that are being used for fuel. The less intense exercise, we're talking like very low-intensity endurance, someone running like an ultramarathon, we're tending to use more fats as fuel.

And essentially when you, if you're listening to any longevity stuff, of course they're talking about being metabolically flexible, being able to oxidize fat for fuel, etc., etc. Again, we're talking about combat sports performance.

So here's a really good excerpt out of this book as well. Fat metabolism training only takes place in the aerobic metabolism area. Fat metabolism can be trained through long-lasting endurance training over 2 hours duration and an intensity under 60% of VO2 max, which is slow as, I don't know how to put that into context, but essentially you'll pretty much be brisk walking to be honest most of the time.

And you're doing this for over 2 hours to improve the ability to oxidize fat as fuel. And it's not exactly something we want to do anyway as combat sport athletes. We want fast, efficient fuel, and that comes from carbohydrates and that comes from lactate as we're in the higher intensity zones.

So essentially fat metabolism can only be increased by longer training loads. The prerequisite is that the muscle glycogen stores are used up, causing a lack of energy, which is what happens when we're doing higher intensity, but then we're using lactate as our main fuel because it's fast and efficient. Where fat is not fast and efficient, and there was essentially, you're trying to not have a bottleneck. And so they're stating here, due to the storage of neutral fat directly next to the mitochondria, extreme endurance athletes are protected against energy bottlenecks. So they're talking about extreme endurance athletes.

So that's just something to take in because even professional boxers who are doing 30-minute fights, they're not extreme endurance athletes in this context. They're intermittent athletes that have a huge, I guess, carbohydrate demand or glucose demand for energy due to the higher intensity. Again, a lot of oxygen being used as showing in Andrew Usher's paper. Will be on the podcast soon.

But hopefully that actually, hopefully it clears up some stuff around that conditioning area. We're going to dive more into this stuff as I keep going down the rabbit hole, talking to more people, bringing more people on the podcast, etc., and really trying to unpack this so it's easy for you to understand.

But there will be a guest on, I'll live stream the guest too. It will be on Tuesday the 7th of May, 10 a.m. Central time. It'll be on the Sweet Science of Fighting YouTube channel. You can jump in there, ask any questions as well. So I will see you then.