Transcription
We've talked about this at the level of the most precision possible, the way in which I would measure it in a patient. You would measure it in a world-class athlete where we have the ability to do indirect calorimetry and lactate testing. But now, I want to talk about it in the way that we train people, normal people.
So, we've talked about this, um, call it, you know, difference, right? Between the lactate level that you measure in the blood, which is now heavily influenced by production and clearance. And then we've talked about the gold standard, which would probably be fat oxidation. But even that can be confounded. But let's take off the table the people who are consuming a high-fat, low-carbohydrate diet, because that confuses things a bit.
If I have a patient and I'm looking at their biometrics, and we do a Zone 2 test based on looking at their fat oxidation during an escalated test of part of a VO2 max test, and it comes back that their maximum fat oxidation, which is, you know, 0.3 grams per minute, occurs at a wattage of 1.5 watts per kilo, that's a pretty average person. And I say, "I want that number higher, both the absolute number of fat oxidation, but where it occurs on the graph." Now, I want you in a year to be 2.5 watts per... Let's talk about two things. One, how they should train, and that means duration, intensity, frequency, etc. And secondly, what we should use as the readout to know we're in the right training zone, given that they won't be able to train daily or weekly or whatever frequency with indirect calorimetry. And by the way, let's assume that some people will want to use the point-of-care lactate meters, and some people will not. So, let's start with what's our surrogate for training zone, and starting with what we knew. So, we learned that, uh, 1.5 watts per kilo was maximum fat oxidation, but we want to increase that to 2.5. So, what metric do you use to train them?
So, yeah. So normally, what I do is, like, starting with the metabolic test, I translate that information into whether it's watts, uh, or or speed, or heart rate. All of them normally, they correlate quite well. And you can individualize it. There are people that don't have a power meter, okay? You can do heart rate, for example. Or or people that just obviously they run or they walk. You can do speed or or or heart rate as well, right? They're very good surrogates. So that's that's a first metric, the surrogate, right?
Then it's about, at least from my experience, the three main principles that I've learned over the years on how to apply this. So, so first is a frequency. How many... Before we go to the frequency and the duration, I do want to go back and ask you another question. We have some patients who don't want to use a lactate meter, either because it's cumbersome or somewhat intimidating. We also add another metric, which is relative perceived exertion, RPE. I'll tell you what my rule of thumb is, but I'd like you to sharpen it, refine it, throw it out, make it better. Whatever I tell patients based on my experience, so I don't know how extrapolatable that is. When I'm in Zone 2, as confirmed by lactate levels, so call it 1.7 to 1.9 millimolar, which is what I target, I can carry out a conversation. So I can spend my entire... Because I do most of mine on a, on a Wahoo KICKR, I put my bike on a Wahoo KICKR. Nice. I can spend the entire 45 minutes on a phone call. Yes, absolutely. But it's not as comfortable as this discussion here. Exactly. I'm a little more strained. Yeah. But if I can't talk, if I feel like I can't talk, I'm too high in the intensity. Yeah. Do you think that that's a reasonable surrogate for people to use across the spectrum, from not particularly fit all the way up to Pogacar?
1,000%. And and I use the same metrics also with people who, like, you know, like you mentioned, they don't want to do a heart rate, lactate meter, or they don't have access, or or they... I get hundreds of emails about, "Where can I do this test?" You know? And I, or or is there anything that I can do, right? So, and I agree 100%. You know, that, um, with everything that we know at the, at the granular cellular level, by injecting fuels and substrates directly into the... We cannot get more cellular level and scientific. That the surrogate or the perceived exertion, it works beautifully. You know, I know that people are coming out with different algorithms based on heart rate variability or the DFA alpha, yeah, you know, etc. But honestly, I agree 100% with you. Um, uh, if you, if you can, I always tell people, if you can exercise, whatever the exercise you do, and maintain a conversation like you and I are doing, you're way too easy. You're probably Zone 1. Yep. Um, um, if you can talk, but it's some form of strain, you can talk for two hours, right? Um, uh, but we're talking, yeah, you're just at, you're just at that threshold of the... Put it this way, the other litmus test I tell people is, the person on the other end will know you are exercising. Exactly. You will not be able to mask from them that you are exercising. Exactly. And in fact, I have, I have many conference calls with, you know, like, um, people that I know to be respectful, but I do it on the bike, you know, work, as you said, you know, they call me and I'm on the bike, either outside or in, in the trainer, and they tell, "Like, you're exercising, right?" Because you can feel it. But yet, I can, I can maintain a full hour meeting on the bike, right? Um, uh, and and and without bothering the other person because they can understand me. But you said, if you cross to the point where you cannot maintain that conversation, that's where you, you, it's because, yeah, you're, you're, you're, you're, you need to breathe much faster because you're producing more CO2, and that's probably because you're already transitioning from the slow-twitch muscle fibers to the fast-twitch muscle fibers, more glycolytic, more lactate, more CO2, more buffering capacity. So it seems old school, but it works beautifully.
Agreed. And and the other thing I do, because I really like people to triangulate and give them a starting point. So if someone has not done a metabolic test yet, and we're just, and that's usually the case, by the way, is that we're starting with just a Zone 2 training protocol. I also give them some, some ranges on heart rate. Now, here I have found much more vari... So the first thing I say is, to do this, you do need to know your maximum heart rate, not your predicted maximum heart rate, but your actual achieved maximum heart rate. In my experience, personally, so this is, I don't know how much I can extrapolate this. My Zone 2 is actually at about 78 to 81% of my maximum heart rate. But I know that for less trained people, it's lower. So I tell people a broad range of 70 to 80% of your realized maximum heart rate is a good place to start, and then make adjustments based on relative perceived exertion.
Yeah, I agree. What do you know about heart rate? And yeah, I, I would agree that I usually also say the same thing, somewhere between 70 to 80. That being said, right? If you want to... It's a big range. Exactly. So you can be at 70, let's say at 1.7 millimolar, and then at 80, you can be at 5 millimolar, right? So you, you're completely away from one. So, but as you said, it's a good starting point. And then, as you very well said, and I agree 100% with you, it's like, yeah, then you, you, you, you tweak it with your perceived exertion. Um, I, I agree. The other thing too with the heart rate, um, and and this is where, you know, the heart rate variability, you know, uh, there, there are different interpretations, you know. So the modern interpretation of variability is the differences between beat to beat, right? And that's where there are different algorithms, right? For me, the heart rate variability, heart rate variability is, it's more at a broader spectrum, and it's more on the, um, you know, the, um, adrenergic activation that you have. So, for example, uh, your fatigue today, right? First of all, normally you're going to wake up with your resting heart rate a little bit higher than normally. So that, that, if your normal heart rate, let's say it's 50, and you're being fatigued, you might wake up with 65. So that alone is a heart rate variability concept. It it varies from from the norm to one day. So that's a red flag that you might be tired that day. Might not happen all the day. I mean, might not be super sensitive, but it is very sensitive for elite athletes, without a doubt.
The second aspect is like, when you go out there and exercise, as you might see, there are days that you were like 130 beats per minute, whatever you think you're Zone 2 is, 130, 38 for example. But some days it's really hard to get the heart rate right, extremely hard. And and you're already struggling at 110 bits per minute or 115 bits per minute, where that's not the norm. That's another deviation. That's a variability of the heart, right? So this is what I've been historically used for heart rate variability, which tells me a lot more information. This is what all the athletes also tell you, like, man, my heart doesn't get up today. You see on training pics, you know, you see when someone is fatigued, they do an interval and they know they always 180, 185, let's say they like to threshold. And today they cannot get up until more than 170. You see in the competition, the first week of the Tour de France, their maximum, maximum heart rate, let's say it's 195. Last week, the maximum heart rate is 170, right? That's that's what I interpret by heart rate variability. And I know that a lot of people might criticize me because, oh, that has nothing to do... Well, I respect all that. No, I think it's macro versus micro. I agree. It's how I read it, as macro versus micro.
I'll share with you an interesting self-experiment I've done a couple of times. It's not pleasant, but it's interesting. If I take a huge dose of a beta-blocker, and the only beta-blocker you can do this with if you have low blood pressure as I do, you have to be careful. But Propranolol is is fine because it really, it disproportionately lowers heart rate, but not blood pressure. But I've done this experiment a few times to test an idea, which is, would taking all of the gas out of my heart rate allow me to push harder and generate a higher Zone 2? And it turns out it does. So if, so my Zone 2 is, you know, just under three watts per kilo. I really want to talk with you about getting over three watts per kilo. I'm still furious because in July, remember, I was at 2.95. I was just kissing on the door of three, and I've actually come back a little bit. I've come back, you know, I'm now at about 2.75 to 2.85. So I've lost a bit. No, I, I think we're going to talk about training in a moment. But what I noticed, so, and for me, I'm at that upper end of maximum heart rate. So, so I'm going to be doing that at about 80, 81% of maximum heart rate. But when, if I took Propranolol, you know, 60 milligrams of a time-release Propranolol, I will be able to get over three watts per kilo, and I'll do it at a heart rate of 68% of maximum. Yeah. But it feels horrible. Yeah. I feel like I'm going to die. It is the worst feeling in the world. It is like somebody has... And it's not pain. It's not like, I don't know how to explain it other than it feels like what it feels like when you're overtrained. It feels like you just can't, you can't get moving. It's like an engine that's being taken from 9,000 RPM to 6,000 RPM. Yeah. But yet, somehow is able to generate the horsepower, but it just doesn't feel right. So, you know, that's sort of my, um, uh, that's that's my drug cheating way to ramp to get over three watts per kilo. But more to illustrate the point, right? Which is when you put the governor on heart rate, you can, you can get there, um, at a lower heart rate, but it, but there, there's just subjectively, it's a miserable feeling.
Yeah, no, absolutely. It's, uh, um, yeah, and this is kind of, in a way, what happens when, when you're fatigued, when you don't have enough fuel, right? So, again, going back to like, my heart doesn't get up today, and I'm struggling, kind of like, you know, it's like if you were taking some beta-blocker, right? But the thing is that it has to do a lot with, and and and for example, and I experiment this a lot too. I, I, I, I try to understand how this works. So I do maybe the intermittent fasting for a few days, and I go out there, and I'm not good at adjusting at that. And I, I cannot do that. I know others can do it, and I admire that. But I can see my heart rate right away, right? When you don't have enough glycogen storages, um, um, um, it's very possible that adrenergic activity is decreased. You need to break down glycogen. And we know that, what it takes to break down glycogen is phosphorylase, right? In the muscle. And that's directly regulated by, um, um, um, um, catecholamines, right? So when there's, um, a decrease in glycogen, this is my hypothesis, right? When there's a decrease in glycogen storages, um, because of the evolutionary mechanisms that humans have, the brain is the boss. The brain says, like, I don't care about your legs, but don't use up all the glycogen because you have to give me, and the liver has to give me glycogen as well. So I'm not going to shut you down completely from breaking down glycogen, but I'm going to slow you down. So I'm going to release less catecholamine, so that you break down glycogen. Now, um, um, the collateral effect of that is the heart, because the heart contractility is regulated by catecholamines as well. So this is why using that my version of heart rate variability, it's quite useful. I've been using it incredibly successfully for 25 years with my athletes, where I see that, hey, your heart is not going up today. You know, usually it's 185, 190, for example, when you do a lactate threshold, for example, and today it was 170. So tomorrow, take it easy, or pile up on glycogen, I mean, on carbohydrates, or take an easy day, and you'll see how you're going to be very responsive the next day, the following day. And in fact, that's happens, I would say, 10 out of 10 times, but let's say nine out of 10 times, right? But I do that with myself as well. And and I see is also, uh, um, uh, that I don't, I mean, I work a lot with the head, you know, so, you know, you think a lot. And the brain uses about 100 to 125 grams of glucose daily, right? When you go, and I don't know that fact, you know, but when you know, when you work a lot of hours and thinking and thinking and thinking and stressed, um, I'm sure that obviously that the brain might need a lot more glucose. So that's that's draining your, your glycogen stores from the brain, probably, and even from the muscles, because the muscle can release glucose, utilize as well.
Yes, muscle can. The muscle has phosphorylase and can be degraded glycogen. And that glucose can go to the circulation as well to feed other organs. I didn't realize that we had glucose-1-phosphatase in the muscle. I thought the muscle's fate was sealed in the muscle. No, it's, it's possible. There are a few studies. I'm happy to send them to you. I cannot ref them out of memory, but, yeah, the, the, the muscles can also release glucose to and export glucose outside.
I assume this is a relatively small amount? Yes. Compared to the... Of my mind. Yeah, absolutely. Exactly. But it's possible too. But what I mean, and I don't know, say, yeah. So, so those days where I'm thinking a lot and I'm very stressed, and I'm not, you know, like dieting or anything, I just go out there and I'm dead. And I'm sure that many people listening to this feel the same way, like, what the hell is going on today? I don't have energy at all today, you know? So, and you will see that your heart rate doesn't get up those days. Um, um, and and you can get to that by just training five hours a week or seven hours a week. And sometimes people say, like, look, I cannot be overtrained because I only train five hours a week. Yeah, but you're overworked. Yeah. And that, that's that, that's a big artifact with your training. That's what most of us are aspired to pre-retire before 60, you know, so we can have more time to exercise, right? And less time to work. But, but, yeah, that's what I do. This, I, I, I, I, I take a day off completely. I, I sleep more. I, I, I, uh, I increase my carbohydrate intake. And the following day, I, I can even break my PR on a climb or something like feel like like a million dollars. So resting recovery is key for that.
Yeah, I, I think this is a very important point. And it's actually something I've only been able to pay attention to in the last year, which is I used to judge my performance by training load. So, you know, and we, I used to use TrainingPeaks when I was training, I don't anymore, but the concepts of acute and chronic training balance. And it was, you know, any day that was suboptimal could be explained by training volume in some capacity. But now, you know, my training volume is relatively low. It's 10 hours a week of total training. That's both, you know, cardio and strength. So that's this is not a lot of training. And yet, when I'm under stress workwise, you know, I'm just doing too much. And I don't even use the word stress, it has a real negative connotation to it. I just mean when I'm overworked, when I'm doing too much, my performance, I have to either adjust my parameters for what I deem successful, or I just have to sort of cut back on the actual training a little bit to make time for more sleep or more relaxation. Um, and I, so I think that's a very important point, uh, that is easily lost.