From Tour Win to World Championship Hunt — Weight, Form & Big Goals

Björn: Hey, this is Björn. Just a quick note before we start — this episode is an AI-generated English version of our original German Afasteryou podcast. The voices you hear are cloned with AI. Enjoy the show. Welcome to the Afasteryou Podcast, where everything revolves around endurance sports and training. Sebastian Schluricke, Björn Kafka and Niclas Ranker share valuable tips and insights here to help you take your performance to the next level. A warm welcome to a new episode of the Afasteryou Podcast. We're now on take three.

Niclas: Yeah, because the others were so good. Niclas had internet problems, had to throw out everything we had. His mother isn't allowed to watch Netflix anymore either.

Björn: Right, and camera off, so new attempt.

Niclas: Finally. You can't see how I'm training my hand muscles here with my rubber bands. Okay. Yeah, but we don't want to talk about that, we want to talk about maybe the most important parameter in endurance sports. Looking good on the bike. No, VO2max. Oh my god, that was flat. VO2max. And exactly, VO2max. What is it? Explain. Or so. Right. We have to quickly mention this. Niclas prepared brilliantly as always, and this time he outdid himself, or rather he overwhelmed ChatGPT. Used up the whole internet for today on ChatGPT. Right, exactly. We always share notes and he slammed down such a monster note block that we then look at together. This time he really outdid himself. Yeah, exactly. But let's get started, Mr. Test-Maker. By the way, I can maybe start by explaining a bit of what I know.

Björn: And then I'll just read out one of the many official or unofficial, who knows, definitions, and then we'll break it down into its components. Yeah.

Niclas: I remember, many years ago I saw this trainability table by Lundby. I don't know, was that 2000-something? And I think it explains it really nicely. It's a kind of diagram. So first, with VO2max, there's this Fick equation, that's actually what it's called, the Fick equation, for determining VO2max. Then we always have stroke volume, so how much blood the heart pumps per beat, heart rate. And then we have the arteriovenous oxygen difference, so how much oxygen is extracted from the blood. And that's the very basic version. This Fick equation is VO2max equals stroke volume times heart rate times, in parentheses, the difference in oxygen volume. And that's the very basic version. Everyone has heard that before. And then there's always a central component and a peripheral component. The central component is the cardiovascular system, very simply put, the stroke volume. So that's where you have the training-induced adaptations, you usually see them after just a few days, you know that, right? You ride a bit of base training, your heart rate eventually drops. And what usually happens, sorry that I'm jumping ahead a bit. All good. Maybe this is interesting for people. Plasma volume increases relatively quickly. I know there was a nice study I once saw on this. They did a performance test and another one the next day. And the day after, people were better. And they wondered why. So they measured plasma volume. Plasma volume had simply increased by 300, 400 milliliters. That's also the effect we know from training. Plasma volume up, oxygen uptake up. That would be the classic. And then we also have, what else affects stroke volume? Of course the proportion of red blood cells, venous return, and then the afterload, cardiac afterload, so how efficiently the blood is pumped out. Right. Right, so then there's another adaptation that takes months. You also see it nicely, the classic athlete's heart. So the heart can take in and pump out more blood, that would be the classic athlete's heart. That's what comes to mind spontaneously about stroke volume. Then, in English they talk about it more, about this central and peripheral component. The peripheral component would be oxygen uptake in the muscle. So we're talking about that arteriovenous oxygen difference, basically the bracketed part in the Fick equation. The AVDO. Exactly. O2 even, sorry. And what does it describe simply, how much oxygen is taken up by the muscle? And there are adaptations there too, of course. That usually happens reasonably quickly. Well, what does quickly mean, there's never really an end, it's a continuum. Vascular function, so better blood flow, working musculature, capillarization, more capillaries per muscle cell, you all know that, capillary effect, like sticking in a straw, boom, water rises, the same thing happens with muscles, muscle cells. Through that we also have more efficient gas exchange, because oxygen is rather sluggish and that's why there are these clever capillaries. And then of course mitochondrial volume and oxidative capacity. So there are more enzymes and then there's better fat burning and better carb burning. Those are the classic things that come to mind for the peripheral component. And these changes naturally lead to us being able to take up more oxygen via the muscle and also having better blood distribution in the muscle. Right, those are the things that come to mind, very basically. And there's also a nice diagram, very old, often replicated by McArdle, I just wrote it down again. So what do we need? We breathe in, oxygen, of course, and then it goes into the blood, so hemoglobin concentration basically. Then comes the blood and the cardiac output, the heart basically. And then comes the peripheral component, so how much is taken up by the muscle. And then broken down further, the aerobic metabolism. And then it goes back to the lungs. It's a circulatory system. And that's basically VO2max, very basically explained.

Björn: Right. We could break this all down a bit more. So we'd have, let me say, the top point, to encompass the whole thing, as you just said, is VO2max, the performance capacity of the cardiovascular and respiratory system. So why do we need this whole thing? Because through the oxygen we breathe in, our body produces ATP, which is the fuel for our cells, our mitochondria, which in turn drive our muscles. So our body uses ATP as fuel, and it's about how your body can utilize the oxygen you breathe in. That goes through the various systems. So first, cardiac output, how much blood your heart pumps through your cardiovascular system. I'd almost say that's probably the adaptation, this so-called athlete's heart, that probably takes the longest, right? Well, it depends a bit on age. With young athletes it probably goes much faster than with older ones.

Niclas: Above all, it's also a pretty lasting adaptation. We thought about it: cells renew permanently in our body, the heart muscle less so. There are nice studies on that. I once did some funny calculation examples, like how long, which phase, takes to adapt. And I don't remember which scientist that was. He once investigated how long cell tissue takes to regenerate. And the heart muscle, which consists mainly of a lot of slow tissue, regenerates, well, of course it regenerates in some form, but the cells aren't replaced. I think up to 70 percent are preserved. I might be wrong, but that really astonished me at the time, because I mean, your brain is constantly being rebuilt. Then of course there are these crazy organs that just completely reinvent themselves. And everyone knows it, you have muscle soreness and after a week at the latest it's gone again. So there too, cell structures have been renewed. That's why you don't want to get a heart attack or anything similar, because the tissue just scars. The cells aren't renewed. And that's why these adaptations, especially in youth, and we'll come back to that later, why there should be different training regimes at different ages, that's also a really exciting thing. You can't just say across the board, here, we do classic pyramid training or classic polarized training. There too you can keep age in mind, and the Scandinavians are further ahead. As far as the trainability of young talents, or rather young people, in Copenhagen, I think there's currently still a study or investigation running on that. I'm not entirely sure, at least I've heard it whispered in WorldTour circles, about adaptations to the heart muscle, especially in young years. That's why this classic phenomenon: if you did sport in your youth, and really a lot, those are the people who can sit on the sofa for ten years and then start again, and everyone wonders, hey, how can that be, why does he get fit again so quickly? It's always a bit unfair, all that you missed in your youth, when you're older it's just, at least when it comes to cardiovascular system and similar, no longer so easy to train back up. Anyone who did something, that's why my appeal to all parents, let your kids do sport, and let them really push themselves to the limit.

Björn: They can handle it really well. That was exactly the point I wanted to make, this high-intensity training is especially important at a young age, because our heart needs that stimulus in the high heart rate range, that over 90 percent of your VO2max, that's where it especially needs that stimulus, and then as much time as possible. I think what I have in my head is that you have the best adaptations to your heart with over 25 minutes of load in this high heart rate range. Then the heart has enough stimulus to say, okay, I'm really going to grow now. And that's especially in the young age, adolescent age, young adult age, where the body still grows the most. Men tend to grow a bit longer than women, or are fully grown a bit later.

Niclas: You know everything, that's wild.

Björn: And it's interesting to do high-intensity stuff there especially. Which is why, for example, if you look at cycling, in youth age cross-country is super interesting, and cyclocross is also super interesting. Because short race duration, and basically that short race duration is full gas the whole time. And that's super interesting, because that builds the foundation for your performance with a high VO2max.

Niclas: In Scandinavia it's standard, long and easy or short and sharp, and then some kind of mutants come out and do quite well, despite a much smaller population than other European countries. So it seems quite sensible. You don't always have to ride at the front in the Nations Cup. Take a few years for it, and then maybe you'll be really fast in the elite class. Because what we've seen in the past, especially what I've seen, is this over-economization of athletes already at a relatively young age. And then you have a 74 oxygen uptake, 0.4 lactate production, and the guy or girl is 18 years old, and you think, yeah sure, they're super strong because they don't blow up. But the older they get, the less trainable the whole thing is. And then you're stuck. They are totally superior in their age groups for a while. But then, when the oxygen peaks really come and they should really push, that's where it's lacking, because the lactate production has been trained away and they've simply been made super over-efficient. And that's not optimal. But now we've totally diverged. But with a small detour, it's quite important.

Björn: Yeah, and it's especially important to understand that in the youth classes, that's why, well, I have a youth athlete who, two years ago I started training with him and that's also when he really started endurance sports, and I basically preached this the whole time. He doesn't have to train an incredible amount. Sure, long and easy is always good too, but especially the intensive stuff is important. And we saw relatively quickly that he can, here in the local area, race for the win at half marathons right away. But I said the whole time, yeah, if you feel like it, just do cross-country, because you have these high intensities much better over 90 minutes, and you don't need the long stuff at all yet. And above all, he also learns better bike handling and so on there. Mhm. And that's why I actually think it's not wrong to just do the short distances, cyclocross or cross-country, until the end of your U23 time, because it builds you a much better foundation for the years afterward. And I also think that, for example, if you take very good pursuit riders from the track, or in the youth squad something like that is trained, especially this four-minute power, which is a classic VO2max effort, that's the best foundation an athlete can have in their young years to eventually be performant in some form, no matter which direction it goes. Because if you have a good cardiac output, the biggest part of your VO2max is already laid.

Niclas: Sure, Bradley Wiggins, Geraint Thomas was, I think, also a pursuiter. And those are these very short efforts, as we know them. Quite interesting by the way, also a Scandinavian phenomenon. They thought about it a bit more in the 60s already, although Ernst van Aaken too, you can't forget him, he also preached the long-easy thing a lot, but the first scientific studies on interval training, Astrand did those in the 60s in Sweden. And there it was first really noticed that if you, they didn't measure VO2max yet, but a critical velocity, between 90 and 95 percent. And the first findings came out. Okay, when we're in these speed ranges, intensity ranges, we have the best adaptations to trigger cardiorespiratory parameters. And they have to work at maximum there. So that was the first time they kind of figured it out.

Björn: Right. Then it goes on with the so-called AVDO2, the arteriovenous oxygen difference. So how much hemoglobin basically. And how many red blood cells you have, how many mitochondria, and how the capillary density is. And the better your musculature, your blood, simply put, is equipped, the higher your VO2max in turn. And these are points that, fundamentally, are partly genetically determined and partly very trainable. So hemoglobin content, for example, is quite trainable through altitude training. Capillary density and number of mitochondria is very trainable through long and easy base training. And that's a bit, I think, what Björn meant with, depending on what age you are, you should do different VO2max training rather than, for example, training someone over 50 now. Letting them ride incredibly hard and tons of over-25-minute intervals, his heart isn't going to grow as much as that of an 18-year-old, for example.

Niclas: But there too I have to say something, it's important to build it back up. Sure, you have to get it medically checked, yeah. But you should, well, if you get into this age, you were once fit and don't do as much sport anymore, definitely do some kind of detraining, because a shrinking heart muscle creates big dangers. I speak from experience. That means things like atrial fibrillation or so. I mean, the heart gets big. And the wiring, the electrical wiring grows along with it. But it doesn't atrophy as strongly, and then you have, every now and then, a few short circuits, to put it simply, and you have atrial fibrillation and a pulse of 160. Uncool. So... My sermon, and I think some athletes know the issue, if you've done a lot, you should somehow stay on the ball. Rule of thumb says, you do 10 percent of the pro volume you had before, and slowly train down. That's of course exorbitant in part. But every pro athlete has to keep doing something. You've trained this huge thing into your chest, and it has to keep running, and there has to be some other way. Oh, by the way, I think, if I'm not mistaken, yesterday I also saw Jens Voigt. He's always around the corner from me here in Unterföhring, and I had just dropped my kids off at school, and this guy came toward me. Up on the Isar dam. I live right by the Isar. And this guy with bare chest, around half past seven in the morning. I thought, who's that? And then he greets me. And I'm like, okay. And then he says, hey. It was Jens Voigt. Alright. Giro is on. So much for that. Even in your ex-pro existence, you definitely have to do something. And the good guy knows it of course. Who at just before eight in the morning is already jogging his first laps before going to work. He does it of course because he loves sport, but also from the aspect that he has this huge pump in his chest that has to keep moving.

Björn: Right. Okay, VO2max basically explained. Now the big question, how do we measure the whole thing? You're probably or quite certainly the bigger expert there than me. Fundamentally, there's the lab measurement with a spiroergometry, and then there's the so-called indirect measurement with field tests, which we're big fans of, I'd say. You have to say, both methods have advantages and disadvantages. It always depends on the application, and you should think about why am I doing a spiroergometry now, or why am I doing a field test, what are my goals, what do I want to achieve. Should we discuss spiroergometry first?

Niclas: Yeah, go for it.

Björn: Explain it. So spiroergometry takes place fundamentally in a lab. If we're talking about the bike now, you're normally strapped onto a trainer, get a mask put on, and then your minute ventilation is measured. So how much you inhale and how much you exhale. That's normally measured via a small turbine. And you ride a test while doing it. In the optimal case, if you're at a good lab, either 30-second steps or one-minute steps. Both work quite well actually.

Niclas: Or there are these awesome ramps that just add like a watt every two seconds. That's like... would be the, let me say, well, I don't know if it's the gold standard, here everyone always says it's the gold standard, but that would be a classic protocol, so that you increase 30 watts per minute somehow, some do it in such a small step, others do it like a real ramp that ramps up very small, yeah.

Björn: Yeah, so I always did it with, I think, 30 seconds, 25 watts, and then it comes down to it, and that's the important thing, with both tests and always when testing VO2max, you have to push yourself to maximum exhaustion. The advantage of the whole thing is, when you do it in the lab, there's the so-called plateau effect. That means you can eventually see in the measurement, okay, you're not taking up any more oxygen now, then you can theoretically stop or you should even stop.

Niclas: Most usually stop automatically too, and this plateau effect doesn't occur in everyone, well, in untrained athletes, it depends a bit on the head too, they sometimes just stop earlier. But they say, okay, can't go on, or they get a little scared or the mask annoys them or whatever. So sure. And also the course of how much oxygen is being drawn, whether it's relatively linear in such a ramp or whether it drops off a bit. Keyword: slow component of oxygen uptake. We can briefly come back to that. It always depends a bit on who's on the bike. If someone has a 40 oxygen uptake, then it's usually relatively quickly done and you may find a plateau. With highly trained athletes, it's usually a bit clearer to see.

Björn: Right. So I still remember, sometimes on a good day or in a good test I could ride one more step beyond the plateau. But that's then mostly just 30 seconds of complete pain and totally blowing yourself up. Although you always, well, the guy I always did it with, Simon, he always said, yeah, that step you could have skipped. Because nothing changed anymore.

Niclas: The first measurements on this were done in, I think it was Cambridge, with A.V. Hill. He basically tied a sack on his back and ran in a circle, well, in a circle, somewhere there, no idea where he was, King's College or however in Cambridge. And he ran around there and measured how much he breathes or rather... what he exhales, and at some point he also discovered that there are these plateau formations. And that was the exciting part. It didn't matter how fast he ran, he couldn't take up more oxygen. And that's where VO2max was born, which is now maybe just 100 years ago.

Björn: Yeah, the good thing about the lab, let me say, is that you have a precise measurement. You know how much you inhaled and exhaled. So that's already very accurate, if you really pushed yourself to the limit. But that's exactly the same with a field test. A bit of the disadvantage is that it's relatively elaborate, relatively expensive. You always need someone who carries it out completely. And as far as specificity goes, it's relatively limited. So you have to always see, when you're on, or you probably know it, when you're on a trainer, that's already a different feeling than when you're on your bike outside on the mountain. Most do their races outside too. Sure, there are also people who race on Zwift and on the trainer. Then it has 100 percent specificity of course. But for everyone else, it's a bit away from the specificity of what you actually perform outside. And on the one hand it's nice to know, okay, what is my absolute VO2max? Where do I roughly stand? But the advantage of a field test afterward is, you don't really have the comparison to outside.

Niclas: Although I think a VO2max, if it's done well, that's the next thing, the equipment has to be maintained. There has to really be someone there who really knows what they're doing. There too you can measure a lot of crap. And I'd say, ten outdoor tests are more accurate than one spiro test. Because simply through the amount of data you can read out significantly more. And you really have to watch out a bit there, that you have someone who... knows what he's doing, and the device is well maintained too. There's this, this small tube that goes from the turbine, if it's somehow too damp or so, then crap gets measured, and the people really have to know what they're doing. And then you can of course derive much more from that, you can also somehow determine some thresholds and so on. There I'd always be a bit careful, especially when it's only a ramp test. Those just aren't that accurate. There's VT1 and VT2. And anyone who's looked at these graphics for VT1 and VT2, it's always very funny. You see an energy consumption and also the proportions of energy carriers, fats, carbs, proteins. And recognizing that from such a ramp, you really stick your neck out far. Whether that's actually the case, I'd be careful with that. I also know, well, there isn't, I know, I don't know if there are programs that can do it well. Most likely you'd have to train an AI on it. But I know that most diagnosticians put VT2, for example, in by hand. Or VT1 too. VT1 you sometimes don't see at all. And VT2 is also like, okay, here the carbs are running out, then we'll put VT2 in there, VT2. It's also some kind of threshold. It's not a 4-millimol threshold or maximal lactate steady state or critical power. It's higher up. So that's not your threshold power, but your ventilatory threshold. And there you always have to be a bit careful. You can find that out a bit better with a longer step duration. But I would actually use a spiroergometry only to test VO2max. And that's it.

Björn: Well, you have to say, what I've seen so far in labs, a lot is also still kind of made up there, because the measured values often don't give a clear picture. Things like VO2max, you just said, that you can measure cleanly if it's done well, but all the stuff around it, lactate threshold, breathing threshold, often gets, or sometimes VO2max too, just calculated and a bit, simply put, made so that the data somehow makes sense. And that's tricky. Especially when so much money is charged for it, that's already worth questioning.

Niclas: What you see is a kind of tidal volume. That's always quite exciting. But longer tests would lend themselves a bit better for that. I know that at the Sylvan Adams Institute in Israel, Tel Aviv, a lot was done on this, a lot researched, like the different tidal volumes. At Fatmax you draw more, at the VLamax you always draw a bit less, so the oxygen draw becomes smaller. There you can see a bit more, where is the maximum pyruvate deficit, the Fatmax zone. But it's all lab. That's always a different setting. There you always have to be a bit careful. Yeah, exactly. Super exciting, good to see. And now, to make the whole thing more complicated. I supervised my master's thesis. I think I've told this before. I tell it again and again. And it was about bike fitting and what effects it has on oxygen uptake. And we did that and were totally happy that the oxygen uptake got higher. Wishful thinking, they didn't pedal more watts at all, sometimes even less, and they were just significantly more inefficient. So that can also happen if you're inefficient. Or you can become more inefficient through a change in your position. That also means, if you're for example on a foreign bike and test your VO2max, then it's most likely different from on your bike. Or also different on a time trial bike, triathlon bike, than on your mountain bike. Because the position of the lungs has an impact too. You have a worse economy. When you sit on the time trial bike, alone through, well, what does worse economy mean, you take up more oxygen, because the lungs are more flat, than when you're more upright. And through that you have a higher or more oxygen pressure, and then it's easier to get the oxygen into the body. And then you have a totally different economy and draw, I don't know, 12 milliliters of oxygen per watt instead of like 10.8 or whatever. That happens too, and that's why you also shouldn't let yourself be too impressed by VO2max values. Well, there's always like, when there's a 91 VO2max, yeah, sick, but A, the question is, is it really such a smoothed 30-second average or is it just a peak? Often peaks get reported, then there's like a 95, but in reality it's like an 89. And the second is, how efficient is this athlete? There's this nice example of this Norwegian, Swede, I don't know anymore. It was a Norwegian. Norwegian, yeah. Who was U23 time trial world champion. World champion, exactly. He has incredibly bad efficiency. And he kept getting worse. That was funny. I once calculated it. He drew 13 milliliters of oxygen, which is incredibly bad. But what does bad mean? He was just not efficient and actually only had a 5.8, 8 watt threshold with a 97 oxygen uptake. And everyone was wondering, that can't be, instead of looking at the watt values behind it, and then a lot becomes clear. Then you have a higher oxygen draw, possibly a higher substrate consumption too, lactate production goes up too computationally. Right, all of it.

Björn: So we get to... Yeah? No, yeah, you go. But let's get to the test model, that's, let me say, more realistic at least, in terms of implementation. That would be field tests. In the optimal case implemented practically. So normally, when we're just talking about doing a field test... that gives us insight into VO2max, you mostly use a 4-minute or also a 5-minute all-out test for that. Actually, if I'm correctly informed, all values between 3 and 7 minutes should give you a quite good insight into VO2max.

Niclas: Yeah, well, it always depends on the movement speed of the sport. I think 7 minutes is pretty good for rowing. For cycling I'm more of a 4-minute friend, because there you can actually take all lactate production rates with you. And if you've also factored out the phosphates via a system I developed back then, then you get a very, very real picture. Three minutes mostly overestimates brutally, that's my experience. And five minutes, many athletes kind of fade there. So four minutes was the thing for me, and then the four minutes were also always a bit too high in terms of the assessment, and then I developed a system for the phosphates, and then I noticed in the lab itself with the measurements, wow, we're really, really close. And that confirmed itself. We let that run at the Hamburg Medical School. Hamburg, I was just going to say. We had a nice study running there, and we were brutally accurate as far as oxygen uptake goes. So that was really cool.

Björn: So you have to say, the clear advantage is, it's practical. So in the optimal case, you grab your race bike, get yourself a climb that's as steady as possible, where you can ride four minutes full gas, where in the optimal case also, I'm always a fan of undisturbed, so I do my four-minute tests reluctantly on a busy road, because you have to, and that's a bit maybe the disadvantage, you really have to be motivated to push yourself to the maximum for four minutes. And in the optimal case you also reach your maximum heart rate in those four minutes. And as Björn said earlier, the nice thing about these tests is, even if you had a test, let me say, that turned out a bit lower, you can simply ride this test, simply put, every week. So if you're motivated enough and well-fueled, you simply, and want to know exactly, okay, what really is my VO2max? Yeah, then go every week and ride four minutes everything that goes up the mountain. And after a month at the latest, after four tests, you'll know it pretty exactly. Also independent of daily form, because it won't be exactly the same four times. Where your VO2max will lie. And that's the nice thing about these field tests. They show you what you can really achieve outside on your bike. And that's also, that's why I'm a big fan of field tests right now, that's what counts in the end in competition. So a lab measurement is always nice, because you get very precise values, but the real values, what comes down to it in the end, how fast you can ride up the mountain, you see that in the optimal case in a field test. And especially if you do that over years, you also see, also independent of power meters, you're getting better or not, because if you're getting up the mountain faster, then it doesn't matter, simply put, what's on the piece of paper afterward for a VO2max, you got up the mountain faster. And that's what you want to have in competition afterward too. You want to get from A to B faster.

Niclas: If you do tests like that, do them seated, please, not standing. That has an influence too. So seated, all tests always do nicely seated. Because I want to factor out this weight component that you bring to the pedals through your body weight. That has influences too. That can easily overestimate by 10 percent. So also gladly, I mean from the power, not from VO2max, but from the power. In the lab you might only see that you become more inefficient because you use more muscles. So therefore seated. That's really, really important.

Björn: Right, so to summarize a bit, spiroergometry very accurate, depending on the lab in the optimal case also a comprehensive diagnostic. The disadvantage is a bit, it's elaborate and expensive and lab-bound. Field test simple, practical, cost-effective. Especially with Afasteryou very cost-effective.

Niclas: And the disadvantage is, well, we have an AI in the background that also rates really crappy tests significantly differently. So poorly paced tests, let me say. I had a case today, an athlete I have little data on, really little. It's basically an athlete who just dove into cycling, and we have practically no real data, and I let the AI run over eight, nine training rides and estimated the oxygen uptake, and now I had him do intervals on it, or also two tests now, and that fit really well. I thought, wow, cool. So I only needed five, six files, and then it was actually pretty cool. By the way, comes to mind, on spiro, there are, of course, also systems you can use yourself at home. The VO2 Master, that one from Canada, that's expensive of course. Or there's this Calibre, I think it's called. This thing for 700 or 600 dollars.

Björn: Cosmed has one too.

Niclas: Cosmed has like a backpack. It looks cool. The K4 or so. But this Calibre costs almost nothing. And is supposed to be reasonably accurate. So we're trying it out in a team right now, and what I've heard is, it's pretty cool for indoor. Outside you can't use it. But I mean, now everyone can buy such a thing for 600 dollars. So if it works, we'd have to test more precisely, then it would be a funny thing of course to see what's happening. But there too... the measurement and the calculation behind it, there's certainly some need for post-processing on the manufacturer's side. I could actually invite someone for that, who has been intensively dealing with spiroergometries and developed one himself. And then realized, ah wait, actually substrate consumption for example is totally different. The buffering also takes a much larger share. So there you could maybe sharpen things up, I'll invite him sometime. But I won't say who it is.

Björn: Okay, then a bit on that. Just to give a comparison between a hobby athlete and a pro athlete, so you can place yourself a bit, where you stand. So what is normal, what is exceptional? You normally say, an untrained adult has a VO2max of about 35 to 45 milliliters per kilogram per minute. I'm currently a hobby athlete. Women lie somewhere at 30 to 40 milliliters. And if we go into the hobby athlete, at least the endurance-oriented range, hobby athletes for men should have 45 to 60, women 40 to 55. And if we go into the range of competitive athletes, you normally say it starts at 65 for men and goes up to 60. What's the highest measured so far? It was, I think, this Norwegian with 97. Yeah. Right, and for women you say, competitive sports range goes from 60 to 75 plus somewhere up. Actually quite good, what you can say, is over 60 is athletic, over 70 is strong, over 80 is world class. So I also say, in the pro range, to really professionally cycle, you need at least a 75 nowadays, I'd claim. Actually toward 80, or most top riders are all somewhere around 80.

Niclas: So I'd say, if you have a 75, good efficiency, and also weigh 84 kilos, you'll surely be a good pro or an okay pro who can also really hammer it out on the flat. If you have a 75 oxygen uptake and... weigh 60 kilos, then you have, relative to body weight, a great oxygen uptake, but on the flat it doesn't help you at all. So that's why big athletes also tend to have lower oxygen uptakes. Relatively speaking, you mean? Relatively speaking, exactly. But they can push incredibly many watts on the flat, and yeah, that's, we ride less mountains, let me say, and that's where it's decisive.

Björn: There you have to, I think, always give people a comparison. The component of weight plays a relatively big role with VO2max, especially with this relative value, so for example an 80. So an 80 in a light rider is of course, in absolute terms, an important... less VO2max than when you have a big heavy rider, or a heavier rider, who only has a 75. Because in absolute terms, the 75 can be significantly more oxygen. So he has an absolutely higher oxygen uptake than the lighter rider, and can of course push more watts in absolute power. Good examples of high absolute power or high absolute VO2max is, I think, a Wout van Aert, he has around 6.5 liters VO2max. That's incredibly much of course.

Niclas: I think really good rowers also have such incredibly, well, when they weigh like 90 kilos and then like 7000 upwards, that's...

Björn: I even think, Blummenfelt, our Norboy, has over seven liters too.

Niclas: Yeah, absolute. And that's a bit you carry through the area.

Björn: Yeah, and those are of course oxygen uptakes. From those you can get incredible amounts of power, because it's super much oxygen of course. And what's always a bit attached, they can of course also train incredibly much, because they can metabolize a lot of oxygen.

Niclas: And they have to eat incredibly much. And that's the big advantage, that they live in a time where food and carbs aren't the devil.

Björn: Yeah, exactly. So, should we briefly touch on the topic of training?

Niclas: Wow, training is, we'll do it really briefly, because it's really a complex thing.

Björn: Then let's, look, we'll do short training, and then I'd actually like to talk about how important VO2max really is.

Niclas: Yeah, yeah, yeah. So we'll do training briefly. So fundamentally you can say, well, if you look at how training adaptations take place. Yeah, that's, I think, you have to first talk about it. Adaptation, yeah. Ultimately, we have HIT programs. That means we have this classic VO2max training as we know it. And then we have, well, we have a high ATP consumption, becomes AMP, and then we have this AMP-activated protein kinase, which then flips this master switch, PGC-1 alpha basically, and that's especially for the muscle. So Type 1 fibers go up, mitochondrial biogenesis goes up, oxidative capacity goes up, also energy transporters, GLUT4, glycogen gets upregulated, exactly the same adaptations you have. When you ride long and easy. So high-volume training has practically the same effects, because it triggers the same master switch. So when you talk about training and training adaptations, especially when it comes to endurance and these peripheral things, the fibers, then you can do that with long and easy too, that's why it makes so much sense to do it, long and easy. And when we talk about these hard things, you can really, really go deep there. And that's quite exciting. And many years ago I had, from Veronique Billat, who has researched a lot there, especially these classic 40-20 protocols she designed. And she defined a bit, from when on is an aerobic training, especially decisive for VO2max. And there it was: from 50 percent of the aerobic energy supply. And from what time does that approximately start? What do you think? No idea. From about two minutes. From two minutes we have a good stimulus. Now you say, why are 40-20s? That's nonsense. No, that's not true of course. Cardiac output stays up of course. And that's why you can, when you ride such short intervals, also reach this stimulus.

Björn: You mean two minutes, basically not over the whole training?

Niclas: No, no, exactly. So two minutes of continuous effort.

Björn: But the one interval.

Niclas: Okay, exactly. So, and then you have a break. That's also a classic protocol. I always say, ride for two minutes. And there we have a really good adaptation. But, and that was Billat, who looked at this in an exciting way... what actually happens when we do 40-20s, and discovered, we can train for a longer time in the VO2max range basically. And there are all these protocols, 30-15, 30-30, and whatever they're called, that are always aimed at, simply put, reaching the time at VO2max or 90 percent of VO2max. How can you measure that? We have two parameters. First, watts. And second is of course... heart rate theoretically, theoretically even lactate. Or you have some mask on, then it's maybe even more accurate. We even simulate that on our platform, how much exhaustion of VO2max is being ridden right now. And yeah, exactly, so the possibilities are there.

Björn: Because the time I had in mind regarding adaptation to VO2max was, that you should at least, if you have a training session for example, get toward 16 minutes over 90 percent VO2max to even generate adaptations in that range. And in the optimal case, when we go toward cardiovascular, especially toward the heart, it should be in the optimal case toward 25 minutes. That's already...

Niclas: At 90 percent, yeah. That's really nasty, right? Yeah, I once calculated it. That's why we have this training distribution, 90 or 100 percent based on lactate production of glycolytic flux in athletes. How much they can train per day. Then you can let someone with a high glycolytic flux push 20 minutes VO2max. With someone with a low lactate production rate, you'd do less. But you can rather hover in this 90s range or even just slightly above threshold. Just slightly above threshold also has, in people with high... with low lactate production rates, also a good stimulus on VO2max. And then, when you look at, I had a study in mind on BMX riders, and there you can really go deep, and that makes it exciting, and we'll get into that next time. What actually happens with such an all-out interval? What kind of, well, what is, which forms of energy supply are especially important? Yeah, well, when you look at 30 seconds all out, capillary density is super important. How many fibers you have, how many fast fibers you have. And especially how much creatine is actually still in the muscle. And at 45 seconds it changes again. There you have like 60 percent capillary density. Then you have sodium-hydrogen transporters are important. Or the sodium-potassium pump, yeah. Have other parts again. Those are things we'll explain a bit more precisely next time. But you see, with all-out things, that between 30 and 45 seconds it's really different worlds, yeah. And at one minute it looks different again, and at two and a half minutes again differently. And at four minutes, that's when VO2max really kicks in, especially when it comes to heart rate. And at two and a half minutes, capillary density is really decisive, which peripherally has a big share in the adaptation. And there you can always think, what do I actually want to train here? And when we go really hard for seven minutes too, then we have like 83 percent VO2max share. So when you give yourself a really, really nasty seven minutes, really vicious intervals, and your heart rate is the whole time 90, 95, almost 100 percent, then you have a brutal adaptation to your cardiovascular system. You can't forget that.

Björn: That's why there are the wonderful four-by-eight minutes from Seiler.

Niclas: Yeah, for example, that's classic. There the pump really goes, and at two and a half minutes you're really pushing your muscles. And there's a really exciting study, we can get into that a bit more, also, from which intervals do I fish out here, and at what intensity should I ride. And this VO2max training is not just HIT, you really have to approach it a bit more surgically, and to say, okay, which intensity actually makes sense? And then of course the component always comes in, what's my daily form right now? So that's already kind of complicated, but I found it quite exciting... to see, what problem, simply put, does the athlete have, is the pump going, or is the muscle limiting? Classic statement, hey, breathing all super, and heart and so on, but my legs blew up, then you know, okay, hey, maybe we should train shorter and harder. And if someone says, hey, legs went somehow, but I have super problems with breathing, and my heart, heartbeat felt in my throat, yeah, then maybe longer intervals. So basically you can break it down to that, but I think many don't understand that. And with 40-20s you have such a nice mixed calculation in part, you have a heart, long, high heart rates. And also, properly do something in the muscles too, yeah, so you can think about, you have this shotgun that maybe processes everything. That's why also, let me say, 20-minute FTP tests, if you rode them twice a week, would surely have a brutal effect on VO2max, because cardiac output is brutally working, and... your musculature is also really mightily working.

Björn: You're welcome to try it out. Twice a week 20 minutes all-out. Have fun. Okay. Björn, how important is a VO2max actually?

Niclas: Yeah, totally. There's always the discussion, VO2max is totally overrated. It's the most important parameter for you, simply. Very simply, yeah. So how many watts can someone push over four, five minutes? That's the most important parameter for me. And then the question is, how... I can turn at the efficiency, yeah. So therefore VO2max is for me the most important. That shows me, well, VO2max in combination with the lactate production rate is really, really important to me. If I have a VO2max that's 75 and the lactate production rate is 75, 0.3, and the athlete is mid-30s, pro athlete, then I know, most likely the writing's on the wall. Not much will come anymore, unless he brings a lot of ambition and we send him to strength training for a few months and try to somehow rebuild him glycolytically, then that works. So always in combination with VLamax. If you have a young athlete, and I have many young athletes, they have like significantly over 80 plus, but all a 0.7 lactate production rate, that's awesome, you can play around with it. And then you make them efficient, and then in two, three years they're in the WorldTour.

Björn: There I actually find, the saying always sticks in my head, when we two started working together, you said, yeah, easy, the bulk of the work is done, the VO2max is already up. You have a high VLamax, but that's not bad. So that's, you always have to... I think this example with the engine is actually quite good. If you have few cylinders but high efficiency, that's nice for the moment maybe, because you can ride a long time and relatively fast. But if you simply have more cylinders, you can simply get much more power out of the engine. And that's the big factor. So a high VO2max will always bring you a high performance capacity. And that's ultimately what everyone strives for. Which is why I also say, especially for youth athletes the main focus should be on building your VO2max as big as possible, and only then start to economize. And for everyone who's basically starting with the sport, I'd almost say, well, it depends a bit on age, sure, but there too the first one, two, three years, the main focus in training should always be on VO2max, because it'll always bring the biggest improvement and gives you the best starting position.

Niclas: Long and easy and short and hard, very simple.

Björn: Right, actually not so hard.

Niclas: Classic polarized. And the fitter you get, the more classic this pyramid distribution becomes, that you, depends on which zone model you have, but I mean, most pros are then in tempo training, because they ride so many races, and you ride them just at tempo. Right. And one more brief on VO2max. When we get to it, the VO2max on your devices that's shown to you is usually not so accurate. So whoever wants to have a bit of fun and has a Garmin can, in their bike training for a week or two, instead of riding with a 90 cadence, only ride with a 70 and crank the watts up a bit. Through that, heart rate will most likely be lower the whole time anyway. Then your Garmin tells you the whole time, super great oxygen uptakes. I had this not so long ago, five years or so, I had built some hightalk stuff, or I especially wanted to see what's going on with oxygen desaturation in the muscle, and tried different frequencies, then I rode for two weeks with such a thick gear through the area, and at some point I had a 74 oxygen uptake, and thought, ha yeah, that would be great, but that... You'll take it, right?

Björn: Well, I would have made a picture, saved it, used it as a profile picture, and said, here, I have a 74.

Niclas: Yeah. I think I even made a picture of it, because I totally... I jumped from a 62 to a 74 and thought, sick, that's how it should be.

Björn: I'd post it directly on Instagram. Yeah. Say here, that's my VO2max. Yeah. Good. Very nice. Then as next topic let's do a bit of... No, now first comes another guest, and then we'll soon talk about training VO2max.

Niclas: Raul Beltran is here as a guest. Don't know if we've already announced it, but Raul was sick last week. But he'll be here next week. It's about nutrition. Right, he's the nutritionist at Caja Rural and is also at Klimatisa, the mountain bike team, also coach and nutritionist. Works a lot. Has, together with Javier Solar from UAE, the coach of Pogačar. Those are big buddies. They have a company together. And we'll talk about it all in peace. It's especially about nutrition in training and also in competition.

Björn: Good guy, very nice. I'm curious. Wait, Caja Rural fundamentally white jersey with this green lettering, right? Exactly. What kind of bikes do they ride, do you know? Okay, nasty question. Green bikes. Green.

Niclas: I know that. Green, glossy, green metallic.

Björn: Perfect. A good hour on VO2max. Thanks a lot, Björn. We'll hear each other. Bye, bye. See you soon. Bye.