Ending The Debate: Zone 2 vs. HIIT w/ Dr. Paul Laursen (SSOF Ep 108)

Dr. Paul Laursen0:53

And then we basically—we did these two research literature reviews that had a big hit in the world of research that you and I are in, James. And then a publisher found that out, and that brought Martin and I to writing the book on the science and application.

James de Lacey2:41

Good man. Love seeing that double whammy.

Dr. Paul Laursen2:41

But yeah, and that's—and then you'll know, James, that the book basically has 10 chapters of science on all these things that Martin and I were looking through. But it also has 20 application chapters from different experts around the world that go in and basically use the principles that Martin and I profess and then on how they apply those principles in the context. The context is so key, right? And I think we'll probably be talking a little bit about MMA today and that sort of thing for your listeners.

And that's Duncan French's area, where he leads UFC in Vegas and globally. So he's written that chapter for us in there, and I don't want to steal his thunder or anything. That's he's the man. But that's just a bit of an overview, I guess, to bring this full circle.

Today, really, I'm caught up in this whole world of artificial intelligence and using these wearables to apply some of this info. So today, one of my biggest businesses is a company called Athletica AI that looks to take all the info that's in that book and apply it for practitioners and coaches like yourself.

James de Lacey4:17

Oh, I love that. We can actually dive on some of the AI rabbit hole near the end if we've got some time to. But I want to start this by taking a big step back, and I want to start with the question, because people often throw this around a lot and they talk about building an aerobic base. And I'm going to ask you, what the hell is an aerobic base, or what is the definition of an aerobic base? Are we just talking VO2 max there? Is there more to it?

Dr. Paul Laursen4:47

Yeah, well, it is—it is ultimately, I think, at the end of the day, it has to be. They're probably talking about your ability to use aerobic energy. And when you use aerobic energy, it's very efficient. Just like you and me right now, we're breathing oxygen at room, at sea level here or whatever, and we have a balance or homeostasis in our body. And I think that's the cool thing about if you have an aerobic base.

Yeah, and I should also mention the key fuel that you're burning at right now here at rest is fat, or at least it should be. It should be fat. So that's really, I guess, the definition of an aerobic base. And I think when people are talking about that, they're saying, yeah, I can—I've got this efficient aerobic system.

Of course, aerobic power is the other thing you referred to there as well, and that's—you're looking at your VO2 max. Now, this is sort of more the high-intensity end of the aerobic system, where you're at very high work levels. You're now still able to uptake and deliver oxygen to the muscles, to the working muscles, to do their job. So a little bit different. I think the aerobic base is down at the base level, and you could go on and on all day. You could walk—we could meet each other in the middle.

I think you're up in Austin, Texas. I'm down in Revelstoke, BC. And if we both had really solid aerobic bases, it wouldn't even—with a bit of food, we'd be just fine walking to one another. But in terms of killing it and stuff, that's aerobic power. Just absolutely going berserk for in any sort of exercise or movement, that's aerobic power, and that's the VO2 max.

James de Lacey6:37

Gotcha. Perfect. That covers that. There's a million directions I want to take this. I'm just trying to figure out where I want to go first with it all. But I think what will be a good way to go down is maybe let's talk steady-state cardio or Zone 2 versus high-intensity interval training, because that thing is just going on and on and on, full stop. And I mean, that's the big thing in sports as well.

Dr. Paul Laursen7:35

Yeah, it's huge. Well, I—this is the beauty of me, is that I just get interviewed by people like yourselves. I just—and I don't follow any of that sort of stuff, so I need—I rely on people like yourselves to tell me what the people are sort of doing.

James de Lacey7:35

Okay, so let me give you the background of where I guess most people are currently sitting, especially within combat sports and a lot of team sports as well. So the idea that we're doing a lot of low-level aerobic base work, which would be that Zone 2, steady-state, and the goal is we're trying to target central adaptations to be able to pull more blood and the heart pump more blood per heartbeat, improve essentially oxygen delivery, and doing that through volumes of Zone 2.

And then eventually doing very short periods, I guess, of high-intensity sprint intervals, repeat sprint intervals, whatever it is, quote unquote, anaerobic work. That's where a lot of people are sitting now.

I know within your book you also mentioned a lot about, hey, you can maximize stroke volume through longer high-intensity or even short high-intensity intervals through rest periods, even through the working periods there. So maybe you just want to dive in. I don't even know if there's a question at the end of that, but maybe I'll just throw it to you and see.

Dr. Paul Laursen8:27

I think you really described the problem quite well. And so this probably goes to a paper that we actually wrote within more the team sport or specifically the football, soccer world. And Martin, my colleague on the book, wrote this. He led this, and I was a co-author on the paper, because my area, as I've just given in the intro, is all on the endurance athletes. And for sure, endurance athletes do a lot of Zone 2, and that's part of their...

Success. A lot of that is also brought from that, right? Endurance athletes doing 80 plus percent of their volume in this very low level zone.

Exactly right. And they get, and that's super critical for them because, well, look what they do, right? Principle of specificity. They go long and they still, within their sport, they have to have that kick and that punch at the end. But more or less, the zone two training helps up your levels of that aerobic base that we started with, and basically it doesn't even dent you in that first bit and then you can just boom, explode and win the race.

So, but in the football context and even the MMA or combat sport context, you've got to kind of question, is that really what I'm doing as a MMA martial arts kind of fighter? And I would say there's certainly elements of that that could be important, but what Martin, he led and argued this in the paper, is that there's so many other contextual things, especially in football, that you've got to take care of, and there's only so many hours in the day.

So specifically with football, and you look at the team tactics that are involved and the chemistry and the culture that's so important around that. Are, is it really wise for a football player to go and just be doing two hours of zone two? That's when, like you kind of allude to, we can get that same aerobic hit in maybe 15 minutes if we do it right.

And again, with all the HIIT science principles that we have in here, we can do this with short intervals where it's just like 10 seconds on, 20 seconds off. You do that repeatedly in the right dosages and you still get the cardiovascular adaptations, right? So the heart, yeah, you get the cardiac output. You can actually be at VO2 max in those types of efforts.

So yeah, it really questions the utility of zone two training for team sport athletes, just like, at least prolonged. It's not necessarily a bad thing and there's a lot of meditation that can go on. Not saying it's bad in certain contexts. Certain individuals will probably need this. If you had, for example, an individual that really needed to potentially shed some pounds, or they were, they clearly looked like they had metabolic inflexibility, they're just too much carb-burning individuals in their day-to-day sort of basis, well then that could, you might have a rationale for applying that.

However, yeah, if time is of an essence and want to work on other aspects, technical aspects, then you can do, and this is argued in the paper as well, you can do technical aspects at the same time when you're doing this HIIT stuff using game-based training. Same sort of thing that Duncan French would advocate within mixed martial art or MMA type, or combat sport training.

James de Lacey12:35

Yeah, that time one's a big one. I did read your guys' new, I think it was an opinion piece you guys put out around that zone versus high intensity intervals and team sports. It's really good. And that time factor is a really important one, especially with people who may be training twice a day, etc. You can't fit hours of zone two in.

But you mentioned as well about being metabolically flexible and the idea around being like a, I'm not going to say fat versus carbohydrate oxidizer, but I guess maybe being more skewed to one end of the spectrum. And for anyone listening, I guess when we're talking about fats and carbs as fuel, typically that's dictated by the intensity of exercise. More higher intensity, more carbohydrates as fuel. Low intensity, more fat as fuel.

But you mentioned there that maybe someone could be more skewed towards using carbohydrates as fuel at low intensities. Is there a way someone would be able to know if that is them without maybe gas analysis testing? Does it really matter in a sport maybe that doesn't have, I guess, prolonged, like ultra-endurance style, I don't know, volumes? Is it okay to be, say, a more of a carbohydrate oxidizer in terms of sporting performance?

Dr. Paul Laursen13:57

Well look, when we perform, we're going to be using all systems, right? We're going to, when we're exercising hard, you're using carbohydrates, no question. But the idea is, and kind of to your question, how do you know without going to a lab and getting hooked up on a metabolic cart? Mostly you can just tell. And I've done a lot of work with a guy named Phil Maffetone who's kind of a legend in the endurance space, but what we term this is being overfat.

And how do you know if you're overfat? You basically look in the mirror without too many clothes on and you can just tell, right? Like, and especially in your culture, James, with combat sports. Like you look at the certain individuals that are just jacked and super ripped and lean, right? Like, that's probably what we want to sort of work towards.

Granted, there's probably different styles that are going to benefit from a little bit of a different body composition. I don't know your sport that well, but there will be these different instances where potentially you could have that, especially when we're talking about body blows and these sorts of things. But usually you want to be nimble and athletic, and athleticism and, so yes, carbohydrates are burned. Do you need to actually fuel the body with those? Not necessarily.

If we go to physiology, there's something called gluconeogenesis. And what happens in gluconeogenesis, if it's a big word, I totally grant it, but break down the word. It's like gluco, that's glucose, sugar. Neo means new. Genesis means to make. And what that means is you and your liver is the bad boy that does all this work for you, right? So your liver basically can go and rip up the fat molecules, fatty acids, can rip up the protein molecules, the amino acids, and it can turn those in your liver into the sugar that you need.

And that's kind of what we've discovered. So this is why you'll know, in the bodybuilding kind of world, they can have like almost pure protein, a little bit of fat sort of diets, the keto diets. That's why you'll see that paleo or keto kind of diet working for these individuals. They don't actually need the carbohydrates because gluconeogenesis goes and can basically put all of the pieces of sugar back in the body if it's needed.

Yeah, and the cool thing is with that, if I can continue, is it's basically keeps your insulin level low. You don't really want to have, when your insulin level, that's the thing that diabetics shoot up when they have a problem handling their carbohydrates or sugar. And basically, when your insulin level is low, that's the body's signal to release a lot of the fuels from your body. And that's probably what a lot of us want to do. We want to lean up, look like our idols, and function like our idols as well, right?

So that's, and that's what that will do. And that's why you'll even see like the carnivore diet being quite successful on certain individuals. Same sort of thing. It's, yeah, and it's because your insulin level is remaining so low throughout that whole thing.

And protein, we're talking about protein here. What do you want to be? We are all made of protein. Our muscles are all made of protein. So we want, when we, and when we give, when we train and we give our bodies the signal to that we've exercised, well, super compensation protocol or supercompensation effect is basically will super compensate. It needs, we need amino acids, we need all those chunks of the protein to go back there and make us jacked again, right? So that's, yeah, there's a lot of rational.

Of course, diet is so individual too, right? So, and it'll be done certain ways for certain people. But, and I basically, and then there, it's an absolute minefield if I'm honest, the whole diet thing. So I just believe that at the individual level, you, the listener, think about experimenting yourself and figure out what works for you. And you keep reading in the various different areas and go from there. And don't be afraid to try some of these crazy diets that some are saying.

I mean, one thing you want to do if you can, if you can afford it, is try to eat as clean as possible, shopping from the outside aisles, not the middle aisles. So stay away from processed sort of food and try to find what God or Mother Nature gave you, whatever, right? So take things from like the farm, like our ancestors kind of would have done. And that's that. That'll, you'll find the more you go towards that, the better outcome you will get with your own body composition and physiological function in my experience.

James de Lacey19:09

And their body composition obviously is just going to help improve your performance anyway in terms of...

In terms of carryover, I want to continue. I know I mentioned the general philosophy right now around Zone 2, and I think extended on that as well. It's maybe a misnomer because we know lactate is a positive thing during high intensity that is used as fuel. I think as you mention, I think it helps us also with gluconeogenesis from the liver as well, or at least signals it or is used to break down there. Perfect. I've been reading a lot.

But there's the whole other area around Zone 2 as well. We talk about the central adaptations, but I think another philosophy that's often talked about using it within, again, combat sports, team sports, is this idea of aerobic and anaerobic thresholds in quotation marks. And this idea that we should try and exercise down these lower intensities because we don't want this buildup in lactate, because lactate equals bad, equals buildup in hydrogen ions, acidic environments, all this kind of stuff that again might not even be that bad.

But essentially exercising at these low levels of lactate and then being able to operate at this lactic threshold at higher intensities—so we're basically able to elicit higher power outputs or operate at higher heart rates but at lower lactate levels. And then that means we're able to do higher intensity work without gassing out because we haven't got over this switch, this isolation switch that everyone kind of talks about. I'd love to hear—I don't even know if I have a question in any of that—but I'd love to hear your thoughts around this idea of in team sports or mixed energy system sports where you're just trying to focus on this idea of keeping lactate so low all the time because you don't want to gas out when you go past this line of where things might be isolated, even though they're not.

Dr. Paul Laursen21:14

Yeah, well, it kind of goes back to your initial question too, talking about the aerobic base or the aerobic power. For again, both of those, if you enhance either of those systems, you are producing energy, ATP, but you're doing it aerobically, which doesn't have as many of the lactate byproducts. Remember, lactate is—like you've mentioned—lactate plus hydrogen ions. Lactate itself gets circulated and rehashed via gluconeogenesis back into glucose. But the hydrogen ions are a signal, and that's the burn that you feel, we think.

So the more you can use aerobic energy—really the burning of both fat and carbohydrates with oxygen—doesn't have as many of the lactate and hydrogen ions byproducts because your mitochondria, energy powerhouses of the cell, are making that clean energy. So the more you train appropriately, and this can be done either way, James, that we were just talking about—so you could do lots of Zone 2 training and you'll get this sort of effect. You'll get an improved cardiovascular system, the function of it, and you'll be burning a lot more fat.

What you always have to keep in mind, though, again, is this whole idea of context. Like, what am I trying to do with my whole—you're probably in the context of the listener, your listeners generally listening to combat sports and looking to optimize that. It kind of goes back again to the conversation we had around the team sports.

And it's like, can we still get these same aerobic adaptations by one, doing a more efficient HIT session, like a 10 on 20 off or a 10 on 10 off, 20 on 20 off kind of thing? And could we get it time-efficiently? Could we do this also using our diet?

In the paper, you'll note we also look at different aspects to keep the parasympathetic system under control or raised. And you do that through optimal sleep, you do that through cold water immersion, all these sorts of things. So yeah, but 100%, you want to have an efficient aerobic system. The more energy you can do using the aerobic system, the more trained up you are metabolically, the better you're going to actually perform any given exercise bout.

And the better you're going to recover in the recovery bouts as well, or any recovery phase that you might have in a competition. If there's all of a sudden you can take a break, you're recovering better and firing up and getting ready for the next bout.

James de Lacey24:25

I'm just going to keep asking questions to you. So even if you're going, say, 10 on or 20 on, whatever, these shorter high-intensity intervals—if we're going by the, I guess, the original that I mentioned around keeping these lactate levels low—are we not in this instance increasing lactate then during, I guess, much higher than you would say during steady-state cardio in that instance? But you're still getting the adaptations, you're still getting similar adaptations to the Zone 2 doing this at higher intensity?

Dr. Paul Laursen24:51

Yeah, for sure. You always—again with HIT—you always need to be careful and mindful of the stress. We never want to be overly stressed. We're not believers in the no pain, no gain philosophy, because the thing that wins out over the long haul in any training program is the principle of consistency.

You want to hit your—you want to hit the target and you want to then walk away from that session. And this applies to weight training, see in the background there, any of these things. You want to—you don't want to be too sore, so sore, fatigued, that you can't go and do this again the next day. So however you skin your cat when it comes to your training program, do it so that you can do it again or something similar in one or two days kind of thing. Or, this is how we periodize and mix things around.

But you never want to have a global stress. And this is where, in the, what is it called, the CrossFit kind of context—it's an awesome business, but they are potentially, can potentially be notorious for going a little bit too hard. And certain individuals that get into that—you want to—the ones that are successful build up to that level where they can—they can be looking ripped and jacked and they're hitting that all the time sort of thing.

So this is where, really, listening to your own body to figure out what's ideal for you. If you're an athlete, or if you have a coach's eye on the system, really, how—yeah, I want to challenge this athlete, but you also want to remind them, pull back and let's—we got to do this tomorrow. Remember, the most important session is the next session.

James de Lacey26:41

That's a really good point around consistency as well. And to circle back as well on the central adaptations that are—it's like this is the thing that's shoved in your face and focused on so much, I guess, within a lot of conditioning for combat sports and just general team sports. But even for this—this is an older book, I don't know if you've read this one, Successful Endurance Journey. I love it. Is that—is that Scott Tinley on the cover there? What? Who wrote that?

Dr. Paul Laursen27:06

Newman. Oh dude, I can't even say the names. Wait, can you see that? No, probably not, I can't. Newman, some German name, I think. Burbul? Okay, no, I haven't seen that one, man. It looks awesome though.

James de Lacey27:29

It was recommended by Lyle McDonald many years ago, so I just decided to pick it up. But they talk in there—I mean, it's an older book, so it could be out of date—but they're talking there about central adaptations. And to actually see morphological changes in the heart, you need, I think, 10 to 15 hours a week of, I think it was low-intensity activity, just to see very small changes, say, in being able to increase blood volume in the heart.

So I don't know how—and then obviously to get elite levels trained, I mean, you need 25-plus hours. And we talked about the time factor there as well. Is that—is that maybe another reason why Zone 2 might not be an effective use of time? Because even if you're adding Zone 2 on top of your technical training, you're going to have to add so much to see some of these central adaptations versus using a high-intensity interval approach.

Dr. Paul Laursen28:26

Yeah, man, I mean, it goes back to that same paper again. Like, to me, it's just a time issue. If you've got 10, 12, 12 hours to do Zone 2 training, well, all the power to you, you go out and do it. But it's—yeah, what is your objective as an athlete? And then can you do that?

And maybe there is a time in your—where that's going to be really good for you. I mean, I certainly love my Zone 2 training and I feel so good for it. It helps me sleep when I go do that training. I'm just saying not every context is that going to be appropriate.

Now it's put into every context. Yeah, that's right. So I would also say that some of that data is a little bit outdated. I think we can imagine we can get cardiovascular adaptations from probably much less, especially if it's done the right way too, right?

Again, so one of the things I'm talking about with 10 seconds on, 20 seconds off, think about that time duration. You're working hard for 10 seconds at in the red zone, and then you're pulling away for 20 seconds. So lot of rest, right? That keeps lactate at bay, and then you do it again.

But it's like, and what winds up happening when you repeat that sequence, that's actually not that hard. Say you're doing this on a bike, and what winds up happening is you do wind up getting, so your heart is beating quite hard, and you're giving that, your heart that, the signals to adapt and get stronger the next time. So you're creating some of those central adaptation that you referred to, James.

And so you can skin the cat a different way. There's no absolute right or wrong way to go about your practice. You can get your aerobic adaptations from HIIT training done the right way, not no pain no gain. And you can also get it, you could get it from low intensity zone two training. Again, in my context as an endurance athlete and coach to those athletes, do a whole lot of that. So just totally depends.

James de Lacey30:47

Perfect. I'm going to go down that road to around some of those intervals, but I want to dive a little bit into some of the high intensity intervals now with some questions around there.

So you've got, I know you break it down like long high intensity intervals, short high intensity intervals. Then you got repeated sprint and, or you've got different types. Now you got six different types, and then you got neuromuscular versus I think metabolic on each one. So there's like a lot of different ways of doing things there.

But I think a really good way to cover this is maybe start with long versus short high intensity intervals. In this instance, I guess the longer version is maybe better suited for more cry adaptations versus the short version. I'm not too sure. Maybe just dive into there what we're trying to achieve with the long versus short, why would use one over the other.

Dr. Paul Laursen31:42

Yeah, so, you know, again, both, there's no right or wrong way to skin the cat. You're talking really here about formats we call them, right? Like a short interval is a type of format. And in the short interval, you're talking like, like I was, the ones I was talking about with 10 seconds on, 20 seconds off. So short intervals, they're usually less than 60 seconds in terms of the switch over from going hard to going easy, right?

And then the long intervals, those ones tend to be two to five minutes. So longer bouts, and even longer recover intervals too, right? The long intervals are, you're going relatively hard for two to five minutes, and then you're going easy for like two to five minutes as well, depending.

And you know, you can act, there's no, you know, initially we often think, "Oh, it makes kind of most sense in our mind to just use a short interval for this purpose on a long interval for this purpose." But the truth of the matter is when we just look to the human, you can get similar adaptations in both of those. So it just depends on what you're trying to attain, right?

The short interval is the one that is the most versatile. And here's the cool thing about the short intervals, and I kind of alluded to this as well before, but you can actually be at VO2 max. Remember, that's your max aerobic power. So your heart is beating maximally, you're actually breathing really, really hard. But lactate, like you referred to, can actually be quite low if you, and this is kind of wild.

Conversely, you know, so you can actually have a low stress system, or sorry, a training system with the short interval versus the long interval. These ones by default are going to have a lot of lactate build up. You think about it, you're going for two to five minutes, right, on that long interval. Well, lactate's going to build up because you're never relieving the system. You're never turning it down.

So this one is, it's really going to be high exercise intensity for a long time. And that's where you alluded to the different physiological targets. That's why we break things down in the book and course that we teach. We talk about the three physiological targets: the aerobic system that we've been talking a whole bunch about, the anaerobic system is the lactate system, and then the neuromuscular system as well.

And this one we haven't really referred to yet in the podcast, but the neuromuscular system is really, you're looking at things like muscle recruitment. Think about punching, like maximal punching and these things. Think about the weights that you're lifting, right? You're just really gritting out and maximizing the neuromuscular system.

Then you think about the soreness that you're getting for days after that. That's the neuromuscular target, neuromuscular system that you've just hit there as well. So those three systems are sort of how we break things down. And the types that you refer to, they refer to how much each of those systems are taxed: aerobic, anaerobic, and neuromuscular. And it's, yeah, again, it's a bit of a complex system, but once a practitioner, especially high level practitioners, really love this system, they can get their head around it and they kind of grasp why they might do certain sessions on certain days.

James de Lacey35:25

And then I guess with the short intervals as well, they'll be slightly higher intensity, right? You're looking like 100%, 120% of velocity VO2 or maximum aerobic speed if you're using that. And then long intervals you're looking at like 90 to 100% maximum speed and those kind of things, right?

Dr. Paul Laursen35:25

Exactly. Yeah, yeah. So short intervals, you've got the scope because they're shorter, you can punch it a little bit harder, right? Like when you push up there a bit. But then the longer intervals, well, you know, just think about pacing a longer interval. You got to dial it down a little bit, right? So the intensity is a little bit lower on the long one. So just kind of, yeah, intuitive. Makes intuitive sense with those guys.

James de Lacey35:53

Is there a way, say if you're not doing a cyclical mode of exercise, so like rowing and biking, it's easy, you can calculate how far you need to go in those time frames based on say your maximum speed in those instances. But what if doing, what if you're hitting a heavy bag or doing something that doesn't have that distance, I guess, measurement to it?

Is there a way you can figure out the intensity that you should go by for say a two-minute long high intensity interval when you're doing something like hitting a heavy bag or doing partner drills?

Dr. Paul Laursen36:44

Yeah, yeah, totally. I mean, really comes down to feel or, you know, we often in the sport science we call this RPE, rating of perceived exertion, right? So just, you know, and the brain is wonderful where it just can do a pacing element in there.

So you know, start with the end in mind. It's like, okay, I got to hit this bag. If you know, if this is the prescription, I've got to hit the bag for 20 seconds or I've got to hit the bag for two minutes, right? Like, so how am I going to hit the bag for that thing? And your brain will naturally, it naturally knows what pace you can keep up.

And you know, if you get it wrong, doesn't matter. It's going to down regulate or up regulate across the duration that is being prescribed there. So just, yeah, don't worry about the intensity. Just your mind kind of knows the what the end goal is. Just give it a duration.

James de Lacey37:43

Yeah, you just to pick a pace you can just sustain for that time period.

Dr. Paul Laursen37:43

Totally, right? And put a word behind it too, right? Like hard or very hard, you know, maximal, these sorts of things, right?

James de Lacey37:43

Okay. Okay, that makes sense. And then I guess on, oh, I had another, I had a follow on thing and I literally just forgot it after I asked that question. But I'll go straight into the into some of the lactate stuff too as well.

Because if lactate is fuel and a good thing, the lactic environment might be protective against fatigue and some of these high intensity, I guess intervals, high intensity exercises, would it not be good to try and be in that environment more often to be able to potentially use that lactate or be more efficient at using lactate as fuel, especially in say mixed energy system sports that have a lot of intensity or a lot of repeated high intensity efforts?

Dr. Paul Laursen38:40

Yeah, I mean, absolutely. Like, really for me it just comes down to, you know, these are signals that are going to create those adaptations. So both the hydrogen ions, lactate itself, these are signaling molecules. And when I say signaling like that, we know that the molecules themselves actually bump around in the various different cells of the body.

And they, remember, we're trying to create adaptations so that we can

Be fatigue-resistant the next day, and that's ultimately what those guys do. Yeah, so when the lactate, you want to raise that lactate a little bit, that's a healthy thing. You want to do that kind of generally pretty regular as well, because as you go to sleep and go on with your day and then go to sleep the next day, the cell is going to be more robust and more resilient the next time. So, yep, it's not a bad thing, never an evil thing. It's all part of the process of training.

James de Lacey39:39

Yeah, because I think it's still viewed as that evil thing, right? Try not to get into the area where lactate rises too much, so we're trying to isolate and almost segregate our conditioning or training so that we're not going there too often. Maybe we're going there once or twice a week, whereas maybe going there, maybe, I'm not going to say all the time, but a little more often, or not being scared of the fact that you're getting into, say, that zone where you're not going to be dead and so fatigued, et cetera, the following day, just because I guess you went above your anaerobic threshold, as an example.

Dr. Paul Laursen40:08

Oh yeah, no, for sure. I mean, don't, yeah, I wouldn't overthink it too much. It is a positive thing to go up there, just be ready to pull back. And again, yeah, this is where I'm really a big believer, despite the fact that I'm hugely into wearables, measuring power output, pace, all the various different things. I really just believe that we need to use these tools to help develop our own feel of training, and whatever is going on in the inside, we don't really know.

We don't have continuous lactate sensors yet. We've got continuous glucose sensors, continuous glucose monitors, but continuous lactate sensors are on the horizon. These are in pilot versions from some of the companies, which is quite exciting. But we don't know at this point in time. The best you can really do is take a finger stick sample, and it's just one sample sort of sitting out there in the middle of nowhere, and it doesn't give us the full big picture of having one that's at regular intervals, coming in every five minutes.

I'm really excited when that happens, but yeah, ultimately, it's all of these tools. Use them to develop your own feel for training, and again, going back, most important session is the next session. So however it feels, don't stress yourself in any one workout so that you can't do tomorrow's session. Be careful of the no pain, no gain philosophy. Work hard, absolutely, train hard, but do it consistently, day in and day out, across your training plan, and you're going to have way more success than if you were doing one maximal crazy session. Save that for your event, your race. That's it.

James de Lacey42:10

Yeah, that actually brings me to a point about how some, I guess, some prescribed, or how some people do intervals. And I guess you could juxtaposition them. One is, say, let's just say you're doing a three-minute round of rowing or whatever, and maybe you're prescribing on one end 90% of your velocity at VO2, so you have this prescribed pace throughout.

Or, I guess, the other way of doing it is going hard from the beginning and trying to finish it as fast as possible. Obviously, you have this slow decline in power output as you go through this as you fatigue, whereas the other one, you kind of have this constant pace.

Is there a time and place for doing something like that, sort of one where you're just trying to go as hard as you can for those three minutes? Is there something you would, I don't know, is that something that would ever kind of make sense within a program, physiologically, when you're just kind of prescribing things based on, say, a long or short, high-intensity approach?

Dr. Paul Laursen43:00

Yeah, now that would be kind of a bit of a bomb. I wouldn't, yeah, like a maximal three-minute row, like that's pretty hard, right? I would definitely, I think circuit training too, right? Because when you see people just do random circuits, and they're doing 20 seconds on, 10 seconds off, and they're just doing all these random circuits of, I don't know, sandbag and burpees and whatever else, it kind of falls into that same realm, right?

James de Lacey43:28

Yeah, totally. This is the circuit training, cross-training, or with CrossFit sort of philosophy, right?

Dr. Paul Laursen43:28

And there's nothing wrong with that, but I would just ask, what is the purpose of it all? I guess it's kind of global fitness, hitting everything. You're hitting everything, but it's not, it goes away from what Martin and I think of as a targeted approach. We really try to look at, well, what's the end objective? What are we trying to really sort of solve? And maybe you're trying to solve with that big circuit system, you're trying to hit everything, and that's great. There's a time and place for that, most certainly.

But yeah, it's kind of, I guess, it's a whole body workout, but it's to me, it just lacks a little bit of specificity at first glance. Maybe there is an overall purpose there, but it's, never is...

James de Lacey44:28

Well, I mean, the way you see it prescribed and the way you see it done, I think the only purpose is to just do work.

Dr. Paul Laursen44:28

Totally. Do work in all your different muscles, right? And hope to heck that it gives you the adaptation that you're after. And probably randomly does help in an individual that's not very well trained, but they have a good propensity. They're fairly young, and they will, when we're young, we're in the mode where we adapt to just about anything, right? You can, the system is very plastic, and it can adapt to that.

The older athletes really need to be cautious with that. It's unlikely to be successful and more likely to injure in the older athlete, like myself. I wouldn't survive very well with something like that. But a, you know, a young, early-20s athlete would probably survive and go well the next day, kind of thing. They wouldn't be that happy with you, but yeah.

And in the, we've written a blog post actually about this with Cedric Luc, and it's really, ultimately, it describes what we call a Type 4 session. You alluded to the different types, so in a session like you just described, the circuit training, you're hitting the aerobic system, you're exhausted, the lactate system, lactate's through the roof, and certainly the neuromuscular system too, right?

Because there's muscle soreness and recruitment all over the place. It was just so random for me. I would just question, what are you trying to do with this session? And how do you feel the next day? And what are you, how are you backing up the next day?

James de Lacey46:27

Yeah, I think also, where do you progress from there? Do you just do more and harder? At some point, there's a programming problem there too. I guess regarding some of these intervals as well, say, let's jump back to the short and long. Are you trying to accumulate a certain amount of time at VO2 max, I guess, based on those intervals? So you're just trying to accumulate, hey, I'm trying to get five or ten minutes at around that 100% MAS or velocity of VO2?

Dr. Paul Laursen46:49

Yeah, this is always the question, and this is where it's so fun, because I'm, you know, we have this team of really smart people that are around me in Athletica. And because the answer, James, is it comes down to the individual. Your question is, well, do I, how do I do this? Do I accumulate a certain amount of time above this in the red zone? And yes, you do, but you have to do it to the individual, right?

So imagine, you know, imagine your grandma, you're prescribing this to your grandma, right? She probably doesn't have too much experience, you know, unless she's an absolute freak, she's not, doesn't have too much experience in the red zone, right? Versus, you know, imagine your fittest athlete, right? Has loads of accumulated time in the red zone, and you can smack them for many different sort of sets.

So the answer is, it really depends on the individual. This is the cool thing with Athletica and wearables is we can now get a historical look at what's done in that individual. So how we do it, and right now, this is just in the endurance context, but how we do it is basically someone comes to Athletica, they download their watch, and their watch, these smart watches, they've been recording all of these movements, right? Like how hard you're working and how long.

And then we, so in the context of running a marathon or doing a triathlon or running, doing a bike race, we plug in the race date, and we've, and then it basically draws a plan that's specific to that individual and their parameters, and it adapts on a daily basis. And we just use Banister fitness...

And fatigue modeling that's been around since the 70s. But anyways, we also get this power or pace profile in them too, right? So you can actually see, like, your grandma would be way down here, but the fit athlete that's in your mind, well he or she would be way up here, right? And they would have completely different profiles.

And then you can just use that profile, how twitchy you are versus how long you exercise, and you can prescribe the ultimate amount of time that's in the red zone. So it's kind of cool, we're pretty excited about it and it's already getting amazing results for our endurance athletes.

James de Lacey49:20

Damn, that sounds really cool. We'll dive into that as well in a little bit too. And I know in that opinion paper you guys published just recently as well you talked about Liv's PhD on the muscle fiber type stuff as well that I really enjoyed that PhD as well.

I might have interpreted it slightly differently, so this would be interesting to kind of go down. The way I saw it was fast twitch athletes, they don't recover as you mentioned, they don't recover as fast from high training loads. So they can take up to five hours versus say a slow twitch athlete.

To me that meant as well the higher intensity stuff might be tougher on a fast athlete and they may benefit more from say the low intensity zone two, because then they don't have that huge lag time recovery, obviously depending on how much they're training. I don't know, I mean I could be way wrong that anyway, but I guess is there anything you might want to add to that or comment on that?

Dr. Paul Laursen50:18

Yeah, so great question. And Martin's the guru here, so I tend to work more with the diesel athletes. And just to just to be clear, well let's just make sure the listener or viewer is clear on this, on the problem here and the situation.

The situation is, everyone I want to really think about you using your coach's eye, we know that in this world that we live in we've got really twitchy athletes, really explosive types of athletes that are out there, right? You'll see them certainly in your combat sports, you see them in team sports all the time. Conversely we have more my world too, right, where it's the endurance world. You've got what we call diesel athletes, right? They're not explosive, but man they can go.

They can go forever and they can actually go at quite high rates forever, for a long, long, long periods of time. That's what we're dealing with, right? So we're talking about, and everyone else is kind of a blend in between. Yeah, these people, you the listener, you've got some profile here. You're either twitchy, hybrid, somewhere in the middle, or diesel, right?

And we can measure that. We can actually, and again this is what Athletica does too, right? It finds your profile and where you're, where your propensity for twitchiness versus diesel. We've got a free course on as well, go to Athlete Primer, athleteprofilingprimer.com, 100% free course, five mini-series that teaches you all of this sort of stuff.

But yeah, where I'm going, and so to your question, the question is well okay, you've got these different people, now how do you prescribe the training appropriately to them? And that's a super question, because what the Liv's paper that you're referring to has uncovered is that the twitchy athletes don't tend to like the long stuff.

And now that's just really Martin's and anecdotal opinion. I can't say I really have a bunch of experience in that one, but the general, and Martin does, right? He works with some of the top football players and yeah, he says to me, "Look Paul, I deal with some of the best football players in the world, soccer, and they're twitchy animals. They don't like jogging laps, they don't respond well to them. They like doing short hits and then recovering and they still get their cardiovascular adaptation."

I would imagine that's also in the combat sport world. You know that you guys would be, there would just be this natural inclination to arrive at that sport as a twitchy athlete, because if I was a twitchy athlete I could kick ass and I would be, I would probably be powerful. I'd probably have a lot of success in that.

But if I'm a diesel, you know, like so of the guys I deal with, then I am and probably a little bit less. And of course there's every, everything in between. So to the long-winded way of saying that, I'm still siding on the side of Martin and the paper that I wrote with him.

Yeah, where it's possible that maybe even a hybrid kind of athlete too that zone two training could be of benefit and they might need that in that context. You know, give it a try, but if you're hitting your head against the wall, consider the alternate option and you might benefit more from these shorter intervals that we've spoken to already in the podcast, right, the 10 on, 20 off kind of thing.

And because your twitchy type athletes might respond better to that. Always look to the individual though at the end of the day and really try to get that feedback and really look them, really closely. You know, how do they seem to be going in these, in the training that you're prescribing to them?

James de Lacey54:22

Nice. I also want to touch on some more of these adaptations as well. So we talked a lot about central adaptations, but obviously we have important peripheral adaptations just around muscles being fatigue resistant. And even with, I guess short, even long intervals, you, I mean you're always getting a blend of everything. But what I guess, what are some that you have that you guys have I guess used around trying to target those more peripheral adaptations?

Dr. Paul Laursen54:49

Yeah, well peripheral adaptations, anytime you stimulate a muscle, you are giving it a signal to adapt, right? And that's, so if, and especially when the stimulus is repeated, this is why HIIT training, even when you repeat HIIT training, those, you know, think about when you maximally recruit, you recruit into those fast twitch muscle fibers that we spoke about with the twitchy athletes. They've got more of those ones.

And the, but the adaptation that you tend to get is actually a fatigue resistant phenotype, or, you know, that muscle, that even that fast twitch muscle, it winds up looking a little bit more like having the slow twitch fiber characteristics. That is because how it adapts, it doesn't lose its size, right? So there's this whole thing called size principle, right? Fast twitch muscle fibers, they're big, large and powerful. Slow twitch muscle fibers, they're smaller but they can go and go and go forever.

Now back to the fast twitch muscles that are recruited during HIIT, well what winds up happening is they start to generate more of the mitochondria that are predominantly in the slow twitch muscle fibers. But, and so you're getting more and more of these powerhouse units, they start being built within the, in the fast twitch muscle fibers. But the fast twitch muscle fiber doesn't lose its power, it's still big and robust. But now within that big and robust fiber, it's got some mitochondria in it as well.

That's what you're talking about, you've been asking. Like, you've been talking about lactate. Well, it's going to handle lactate now. Yeah, it's, you know, all the, any lactate that that big powerful muscle fiber is generating is just going to be quenched and producing energy.

So, that's the adaptation. It's not a bad thing, you're not creating a less powerful muscle fiber type when you repeatedly stimulate it. You're just creating fatigue resistance because of the mitochondrial density, ultimately, that you're increasing in it. So, that, and this is again goes back to if you've got a twitchy athlete, which the majority of your MMA combat audience are, you want to hit those repeatedly, those higher exercise intensities.

That's probably why the cross training, circuit type training works a little bit. Because if you can repeatedly stimulate it, because it's high intensity, you hit it a lot. But you want to, yeah, you want to really manage that so that it's, again, you can do that again the next day. So it's, where do you turn that session off? And that's the art of the coaching that you're doing.

James de Lacey57:32

Gotcha. Are there any guideline protocols you could recommend for someone who's maybe looking to do these repeated, I guess, more higher, more maximal, I guess, intervals to target some of these adaptations? Would it be as simple as some kind of repeat sprint protocol on a bike or whatever modality they choose?

Dr. Paul Laursen58:05

Yeah, absolutely. And again, this kind of goes back to the book. The two other weapons or formats that we didn't speak about were repeated sprint training and sprint interval training. You described sort of the rowing ergometer one, was the protocol, it was almost like a sprint interval training except it was too long at three minutes. But if you did that for 30 seconds to 45 seconds, that's a sprint interval.

And then, you know, repeated sprint training, this is the cool thing with either of these other two, sprint interval training or repeated sprint training, the calibration of them is very simple. Because for the intensity, just all out, just go max out, just balls out. Exactly, right? So it doesn't matter, like every single session is...

Balls out. But it's ultimately probably better referred to as short sprints or long sprints. So the rowing example is the long sprint, but you can also just do these for like 3 to 7 seconds—that's really actually called repeated sprint training. So 3 to 7 seconds all out, balls out, and then anywhere from 15 to 45 seconds of recovery. That's a good little format to use.

Now think about it: we've been talking about recruiting maximally these big motor units or muscle fibers, which we want. We want to hit those because we're going to need them ultimately in a competition. And then we also want to continually be able to use those, so now they're not just maximally recruited but they're being fatigue resistant as well because we're going to recover the next day.

And then where do you turn it off? You turn it off—again, this comes back to the art, and I just keep emphasizing throughout this whole thing: the next session is the most important session. Don't go so hard in your session—it's hard, right? Because you're absolutely jacked up, the energy level's super high, the endorphins are running.

It was so funny, actually—I saw this yesterday. I was mountain biking in Revelstoke in BC, and we were booting down a downhill descent. I live in the mountains in Revelstoke, and I was booting down and we had a dog with us—a young dog, 3 years old, larger than life. The dog was racing down, and of course I'm just absolutely booking down this hill through berms and all these things, off jumps.

I can just hear the dog behind me, and I finally get down to the end and the dog is just absolutely jacked, right? And there's this squirrel goes up in the tree, and the dog starts trying to go up the tree.

I could just sort of see that endorphin. So the same thing happens in us, right? The same thing—that energy in that system really keeps going, and you might want to continue to push. But this is where you really need to develop your own feel for training if you're an athlete, or feel for training if you're a coach and you're watching it.

I don't know where you kind of call it, but you've got to call it before you're going to get a little bit too down into the red zone. And then, because again, you're going to be so effective and moving in the right direction if you turn it off and you can repeat again tomorrow.

James de Lacey1:01:26

Is there some kind of upper body versus lower body adaptation that goes on depending on the modality you choose? For example, if maybe I participate in a sport that is, say, more upper body dominant and I'm doing my intervals on a bike, is that still going to help potentially transfer and give me the endurance adaptations in my upper body?

Dr. Paul Laursen1:01:53

Well, no—what you're, it's not really. But what it is going to be doing, James, is targeting the most important recovery tool, and that's your heart. We've been talking about the cardiovascular system, right? That's what you're doing it for: you are trying to make a nice big heart and lungs so that you're—and that's probably why you're using the lower body one. So that's why work on the bike can be really good.

You can again speed the adaptation too. You could have, you could add heat into the equation as well, so if you had even a period of time in a heat chamber, you could actually speed that sort of adaptation there as well. But ultimately you're looking at the greatest recovery tool that we have on our person, which is the heart. And we're trying to get that heart nice and efficient so that—yeah, and it's a good way to, if you have gone really hard upper body on one day, like we're just talking about, and you need to come off on arms, well then do a lower body, like do a bike sort of session.

And, depending on the context, mix up polarized with the HIIT sort of HIIT training that's in there, so that you—and make sure that you're breathing hard and record your heart rate as well if you can.

James de Lacey1:03:15

So as a very crude example, so if I was in, say, a very upper body dominant sport and I did, say, all my peripherally targeted intervals on, say, a bike, would most of those adaptations then occur within the legs and not within the upper body because the legs are the ones doing the work? Or does it just become a systemically peripheral adaptation that kind of covers the whole body in the substance, if that makes sense at all?

Dr. Paul Laursen1:03:41

Well, if you're doing it on the bike, so the muscles that are stimulated are the ones that are going to get the peripheral adaptations. But because the heart's involved to get the O2 down there, it will adapt as well.

James de Lacey1:03:41

Gotcha. Yeah, no, perfect. And I know you got to go to a meeting very soon, so we'll wrap that up there. But where can people find you, Paul, and keep up with what you're doing?

Dr. Paul Laursen1:04:11

James, I am on—I mean, if you want to tag me in anything, I'm Paul B Laursen on Twitter if there's anyone that's still on Twitter. But otherwise, hitsci.com is where you find all the info. Especially Duncan French's Combat Sport—it's one of our, across our series of suites of courses, the Combat Sport by Duncan French of the UFC is arguably our most popular course.

So I would—yeah, I don't know what it is, but there's something—I think Combat Sports and MMA must be trending, but you would know more than me. But yeah, people—a lot of people buy Duncan French's HIIT Science course. So it's hitsci.com. It's very affordable, I think it's less than 200 bucks. But it will really kind of equip you with all the tools that we've been speaking about in here and even more specific. You can see how Duncan French actually caters his HIIT sessions for the various different Combat Sports that he deals with, especially at UFC.

James de Lacey1:05:49

Perfect, perfect. I'll link down in the description so you guys can check it out as well when you're watching or listen to the replay. But thanks for coming on, Paul. I appreciate it.

Dr. Paul Laursen1:05:49

Oh, it was awesome. It was a super fun conversation, James. Thanks for having me, man, and all the best with your work.

James de Lacey1:05:49

Cheers.