Welcome to the Empirical Cycling Podcast. I'm your host, Kolie Moore, joined as always by my co-host, Kyle Helson, and I want to thank everybody for listening as always, so please subscribe to the podcast if you have not yet already, and give us an iTunes rating, that really helps us out, and tell your friends, share the podcast. That has been so great for us in the last couple weeks. We really appreciate that from everybody, and we hope you guys are getting as much out of this as we hope you are. And if you'd like to donate to the podcast, you can do so at empiricalcycling.com slash donate. notes on the website. We've listed all the studies that we're going to be talking about here today. And if you have any coaching or consultation inquiries or questions or comments, you can please send an email to empiricalcycling at gmail.com. And if you would like any merch, you can go find podcast merch at empiricalcyclingpodcast.threadless.com for all of your bathroom adornment needs. We have shower curtains and everything. So today we're talking about VO2max and ramp tests and stuff like that. But Kyle, give us a quick intro on just VO2max generally. So I think typically if you have been involved in any sort of endurance sport for a long enough period of time, eventually you'll run into the phrase VO2max. And VO2max is usually quoted as like the... Maximum amount of oxygen or volume of oxygen, hence VO2, that your body can use during exercise. So be it if you're running, swimming, biking, whatever, skiing, cross-country skiing. And usually people like to, just like with every other impressive number that they can, they like to bandy about big numbers because you should be impressed by their bigness. And so people like to, because you can measure it in a lab, people like to be able to say, oh, hey, I got my VO2 max tested and it came out as X or Y and, you know, here's where that stacks up for what is considered an elite athlete or a, you know, above average athlete or whatever. And then you hear about freaks like Greg LeMond or something who tested it, you know, top 10 all time or something like this. And I think there's also a lot of, you know. Sort of lore about VO2max as well. Like I remember one thing I heard years and years and years ago that like some pros were afraid to get their VO2max tested because they thought it was untrainable and that it would like reveal what their like genetic ceiling was because that was the number and they could never hope to raise that number and so that would kind of put a permanent ceiling on how good they could be. Yeah, and we're going to talk about training and trainability of VO2Max in a future episode. But today, we're going to talk about something that I came across while we were discussing how we should structure the upcoming VO2Max episodes. As I do, looking up some more esoteric questions on VO2max, because I really like to dot my I's and cross my T's, I realized that there are probably some misconceptions about the one thing that I see a lot of people using now, which is power at VO2max, and also how VO2max is defined and measured. So we're going to talk a lot about this. So the first thing that we need to talk about, if you've gone into the literature, This is important for the measurement aspect is that you will often see VO2 max with a dot over the V. This is the first question that we can answer definitively for everybody, which is that the dot means a flux, a flux of the volume of oxygen. Flux? Well, so in physics, flux has to do with an amount of something that is passing through a defined surface area. So... So we're going to kind of get into ramp tests and power at VO2max or MAP or maximal aerobic power. So ramp tests. Now these are getting very, very popular because they are getting used for FTP testing and we're going to skip over my very strong opinions on that for now. So Kyle, what do you know about all of the ramp tests that are happening these days in respect to VO2max? So typically a ramp test for people who aren't aware is a test that is a relatively short duration, so sort of in the 10-minute total time range ballpark, and what you do is you start off at some very easy level, say 100 watts, and then every 30 seconds or a minute or some fixed interval, you keep bumping up the power output. a fixed amount. So say it's every 30 seconds you bump it up 25 watts or something like that. And then they typically look at whatever you and you run that to exhaustion and whatever the last like step is that you fully completed. And usually they have some requirement that your cadence stay above some number so you can't be grinding along at like 10 RPM on the last. Yes, but also I've seen a lot of the papers I've looked at where they require the cadence be between like 60 and 90 RPM or they just like fix everybody at 60. So like it's weird for an experienced cyclist to do some of the ramp tests that are out there. But there are different protocols. Yeah, and like I said, yeah, there are different protocols, the step size can vary here and there, but in general, they look at the last chunk of time that you completed before you blew up and stopped the test, and they call that your maximal aerobic power or peak power output or whatever the terminology they want to use. Right, and so where does this test come from? Now, this test is... I'm looking at my watch like it's going to tell me the year. This test is, well, it's 930, so this test is now... It's exactly 100 and... Actually, this test is about 97 years old. So it was introduced in 1923 by A.V. Hill and his co-experimenter Lupton, whose first name I forget. Here's a direct quote for VO2max. The oxygen intake during an exercise intensity at which actual oxygen intake reaches a maximum beyond which no increase in effort can raise it. And since then, this definition of VO2max has actually been excellent. Hill and Lupton did a great job at defining VO2 max. And that's where this RAM test actually comes from. It's very practical. So the criteria to prove VO2 max doesn't just mean looking for the highest value of O2 uptake that you can measure in a single test, because the danger is that people unfamiliar with pushing themselves hard will not meet their maximal oxygen uptake. So you have to see a large increase in the intensity to occur without an increase or with only a very trivial increase in oxygen uptake to be sure that you are really there. So what we're looking for in a quality VO2 max test is a plateau in oxygen uptake for a big uptick in the power output required. And that makes sense, I think. If you're doing a ramp test at home on TrainerRoad or something like that, you can't know. Well, I mean, that's a thing about the test subject and not being able to measure your actual O2 consumption. And also that's, they think that they're measuring FTP and we're going to skip over that for now. So the other thing that needs to happen, which we're going to get deeply into very soon, is that the test needs to involve a quote-unquote large amount of muscle mass. And this definition is going to get us in trouble a little bit. And we're going to have to actually spend a whole episode on it, which will be coming up soon, don't worry. So there are some quote-unquote additional criteria sometimes mentioned to establish VO2 max. And spoiler alert from the future, which is now, these should all be ignored. So we're going to skip some of the sillier trivial things but you know most of them are things like blood lactate value has to be at least this to make sure that the test was maximal or the RER value respiratory exchange ratio this needs to be at least this value to make sure it was maximal or heart rate and none of these things over the you know the last 100 years have proven to really be good criteria to establish a good maximal test because for everybody, they're a little different and even test to test, these things will all be different. So VO2 max, seeing that plateau is really the gold standard to establish it. Yeah, so when you see studies that use these additional parameters to establish, yes, this was this person's VO2 max, we did not see a plateau, but we saw these things, you can ignore them. And so I think when you are looking at studies out there in the literature, you should always be careful about the methods that they used to actually verify that they had had the athlete or athletes, whoever, reach this VO2 max if they were not actually measuring oxygen consumption. Or if they measured something called VO2 peak, which we'll get into in a second. So a typical ramp test should in theory be 8 to 12 minutes long. This seems to be the sweet spot between... being too short and being too long in order to really get somebody's maximal O2 uptake. We're going to look at some studies on this in a little bit. But the common wisdom with it not being too long is that you don't want to fatigue yourself before you really get to the business end of a maximal test, which is where, you know, getting to the maximal whatever, maximal effort, maximal oxygen uptake. And the final value... of this test is sometimes called a PPO or Peak Power Output but was more often called Wmax in the literature or Wattmax or the maximum wattage that you reached during this test and we're going to call it Wmax also but it's basically the final ramp test power value at which VO2max was reached. If you dig into the literature a little bit though Most papers will have their own terminology and they'll also have their own test protocols. Some are a step test, some are a smooth ramp. So don't get hung up on that because that's where Twitter arguments start. All right, so what is VO2 peak? Now, this is the same units as VO2 max. Oh, by the way, the units for VO2 max are either liters per minute or milliliters per minute per kilogram when you normalize it to body weight. Common numbers that you will see bandied about for extremely elite male aerobic athletes are high 80s to low 90s are kind of like those super freak numbers like Greg Lamond was something like 92 or something like that and I think like peak Lance was upper 80s and I think Froome is upper 80s, things like that. Oh yeah, and so for a 65 kilogram rider this will be about 5.8 to maybe 6 liters of oxygen per minute, something like that. It's a lot of oxygen. Typically, for average athletes, we see anywhere between 3 to 5 liters a minute, average well-trained elite athletes. So VO2 peak has more or less the same definition. of VO2 max except VO2 peak means that there is not a confirmed plateau corresponding to an increased work rate. So VO2 peak can also be established in a single exercise test as the highest value seen. Any test, doesn't matter, like could be four minutes constant work rate, could be a ramp test, could be anything. So the reason that it carries this distinction of being separate from VO2 max itself is that it cannot be determined if someone reached their true maximal O2 utilization and transport, like we see with a good plateau. So that is the reason that you see and sometimes hear about VO2 peak. It's not like VO2 peak is higher than VO2 max. It's just that that's what you've seen without confirming a plateau. Although somewhat controversially, VO2 peak can be established as a VO2 max measurement if someone has repeatedly performed more tests, and these are usually called in the literature verification bouts, of different and increasing intensities either following the ramp tests or as just the tests themselves, like doing a couple maximal effort Intervals. Let's say you do a test that's 10% higher work rate, power output, than the RAM test's final power value until exhaustion, right? And in the RAM test, you only saw a VO2 peak, you didn't see a VO2 max, and you're looking for the same maximum VO2 value. And if you get two peaks, there's still a chance that... You know, that the athlete stopped working at the same oxygen uptake and is still not their actual VO2 max. And if you do it iteratively three or four or five times, you know, and you keep seeing that same peak, VO2 peak, then it's better established that it's somebody's VO2 max, but it's not the gold standard. Yeah, that makes sense. Especially if it's, then you are really relying on the sort of mental fortitude as well to like keep hitting that value as opposed to actually verifying that like effort went up but oxygen consumption did not go up. In a lot of studies with untrained or just recreationally average subjects or recreationally active subjects or whatever qualifies for quote unquote moderately trained subjects, VO2 peak can actually get reported as VO2 max and the authors of the paper will not mention that fact. So make sure you look at not only the tests but also the training intervention in some of these papers where Possibly doing the training will actually help somebody reach their true VO2 max. So if you found VO2 peak first and VO2 max later and VO2 max did not improve, you will actually see that as a positive result that the training helped somebody improve their VO2 max when really it was just helping them reach their VO2 max. Right. Because we don't really have a great idea what limits somebody there. I mean, we do have some ideas, obviously, but nothing absolutely definitive. So it's always a question mark. It's always one of those things where there's a fudge factor sometimes. So the question does remain whether or not barely or moderately trained individuals have mechanisms of fatigue that stop exercise before they can reach VO2 max or if there's something else like motivation. I personally think it's a combination of Both. That would kind of make sense. Like, you imagine you pull your average moderately active weekend warrior, like, you know, if they haven't done this type of training before, or if they haven't really dug deep like this before, you know, who knows how good you're actually going to be at it. Now we go to the next piece of criteria for VO2max tests, according to Hill and Lupton. the large portion of muscle mass. VO2max measurements. We should also talk about this for a second. We'll get really in-depth with this another time. And we're going to mention this in a cursory fashion right now. So VO2max measurements are exercise mode dependent. This means that VO2max tests... Okay, so let's take, for example, triathletes. So VO2max tests in triathletes will usually see the highest VO2max values in running, second is cycling, and then third is swimming. So these are not small differences either. It's not like one to two milliliters per minute per kilogram, you know, out of like, if somebody's testing at like 60, it's not like... going to be 62, 60, and 59 for like running, cycling, swimming. It's going to be like 5 to 10, meaning there can be like a 10 to 20 milliliter per minute per kilogram difference between running and swimming. Interesting. Yeah. And this is one of the reasons that cross-country skiers have some of the highest view to max values ever recorded because they are using all of their muscle mass and we've barely got enough blood to supply Oxygen to all that muscle mass. So your maximal oxygen moving is like totally maxed out a lot in cross-country skiers. And that may be one of the reasons that they have higher VO2 max because is possibly their circulatory system meeting demand, the higher demand that they have than cyclists and other modes of exercise, possibly? Possibly. Although I think they're, They are in that sort of like the highest numbers for cross-country skiers and stuff are sort of in that 5 to 10 milliliters per minute per kilogram range more than elite cyclists. So they're, you know, some of them, I think the highest ones there are like mid-90s. Yeah, mid-90s. As opposed to like upper 80s, low 90s. Yeah, exactly. Yeah, it's not the hugest difference percentage-wise, but it is there. And at that level, it can make a big difference. Yeah. And in performance, it can make a difference too. So this is one of the things that Hill and Lupton recognized in 1923 is that something like arm cycling, I don't know if they had it then, but something like arm cycling is not going to get you close to your true VO2 max, even if you see a plateau in O2 uptake. So yeah, so while there's not a lot of muscle mass involved, one of the things that helps determine Maximal Oxygen Uptake is the rate of maximal oxygen utilization. So we're going to talk a lot about that in a future podcast episode that is going to see a lot of gray area when it comes to this kind of thing and measuring VO2 max. So, you know, if there's anything people can expect from us, Kyle, it's that we go straight for the gray area. So it depends and... So the question is like... I'm sure a lot of people are thinking it because I had the same question. So if you're a cyclist and you are doing a VO2 max test and you could probably measure a higher O2 uptake if you were on one of those attack bikes or is that a thing? Assault bike. Assault bike, thank you. So if you're on one of those or if you're on an elliptical or if you're running or if you're cross-country skiing and you could get a couple points higher, does that make your cycling? Test, Less Valid? That's a good question, because is that your true Viotimax? Could you get a little more if you used your arms? Is that your Viotimax while cycling, but it's not quite there with the running? We'll get into that. But it is a good question, and I appreciate everyone who just had that thought. So, a ramp test. So, the idea behind these is pretty obvious, again, that you want to Increase the work rate on somebody and measure the oxygen consumption because there used to be, and there still is in a lot of places, assumed that there's a totally linear relationship between power output and the increase in oxygen required. But this is an episode of gray area and monkey wrenches starting right now because to the extent of my knowledge, this relationship holds true at and below FTP. Above FTP, well, at some point we're going to talk about the gritty details in the metabolic shift that happens over FTP, but not right now, sorry, we don't want to take a three-hour detour, but the most important thing to know right now is that the metabolic shift that happens over FTP or lactate threshold or whatever you want to call it, There are multiple metabolic contributors to power output above FTP, not just oxidative metabolism. And if you actually look in the last couple of years, there's a lot of exercise physiologists who are just discovering this fact. And it's really freaking them out. Because it used to be like, we're going to have our athletes do exercise at like, not even used to be, you can still read a lot of papers that do this. at like 75, 80% VO2 max and or 60% VO2 max and that can be threshold for some people and it's like just chill endurance riding for others. Right, yeah, yeah. Okay, so this is kind of one of the more important things that we're going to talk about here and this is going to be kind of the crux of everything going forward. So keep this in mind as we go through this episode. So there's a lot of studies out there that look at different ramp rate protocols also and how they elicit VO2max. So in general, the shorter and harder a ramp test is, the more likely it is to elicit VO2max, right? Because you're not getting as fatigued by the end. So incremental tests, we can either go step test or ramp test. Typically, we see step tests for VO2max, in the literature anyway. If you ask me, they're more or less interchangeable in terms of eliciting VO2max, but they're not interchangeable in terms of threshold testing. We're going to talk deeply about that another time. As usual, you can take a drink now. So let's look at incremental test rates. given in terms of how often the intensity is increased by 25 watts. So the first paper that we have linked in the show notes is the Adami paper, and they look at several step tests. They increased 25 watts every 15, 30, 60, 90, 120, 180 seconds. If you look at the maximal oxygen uptake, The plateaued VO2max value that they show you in each of these, I would say the 30, 60, 90, and the 120 second tests, you know, those being the step durations, all elicited what I would determine as the same VO2max, 3.54 to 3.56 liters per minute. So it's pretty tight. 15 seconds didn't quite get there, 180 seconds didn't quite get there. So, the question is, did all of these show the same power at VO2 max? Because it got the same O2 uptake, right? Right. Like, within .02 liters a minute, which is awesome. And that's always going to be the next question is, well, okay, I have this number, now can I actually use it in a race? Right. in a race. Hold on, guys. I'm 10 watts above my VO2 max power. Okay, so if we look at the four tests that hit the VO2 max, their final wattage, what we would consider to be their VO2 max power or their maximal aerobic power is all different and not like by 5 watts. So in order, the 30, 60, 90, and 120 second steps, tests. The population average was going in order from the short to the long, 366, 320, 297, 282. Wow, that's a big swing. Yes. So we have about an 84 watt difference between the 30 second steps and the 120 second steps. Which is over 25%. Yeah. Yeah. With the same VO2 max value when actually measuring oxygen uptake. So what is their power at VO2 max? Right. Okay. What's the average of those four? So we're going to look at another study also. This is the second one in the show notes. They performed one, three, four, seven, and ten minute stages. Wow, that's long. Yeah, it's ridiculous. And the maximum power reached during these tests also went down as the stage durations got longer. So only the one minute stage actually elicited the highest power output, sorry, the highest oxygen uptake, the Truvia II Max. The others appeared to... but they were all one to two milliliters per minute per kilogram lower. So enough that you would notice, right? So the other thing is that only the one minute stages were completed in the normally prescribed eight to 12 minute range, 11.3 minutes on average. The rest were 26 minutes or more. It's quite long. Yes. The standard deviation on the shorter Of those, the three-minute steps, 26-minute average, the standard deviation is 1.4 minutes, so let's say three sigma on the short end is about 21 or 22 minutes minimum. It's a long test. It is a very long test. So, you know, it kind of makes sense now when we see that somebody might fatigue, by the end, they can't quite put out the same power output or reach the same oxygen uptake. Getting Tired, right? But it also makes sense that seeing the 130 to 120 second range stages from the previous paper, you know, being the ones that show true VO2max value. Also, those subjects were less well-trained, so they probably had... For the first test with less well-trained subjects, because they're less well-trained, they are not going to be able to last... During the ramp test for as long as the well-trained cyclists in this longer study of the 1 to 10 minute stages. And so you're going to expect those shorter tests to hopefully be in that sweet spot range of 8 to 12 minutes. If you are designing a ramp test, you need to know your subject. So if someone has a 400-watt FTP and a 480-watt five-minute power, if you start at 100 watts and increase 25 watts every minute, you're going to take 12 minutes just to reach FTP. Yeah, that's a lot. And that's like going to be super boring as that person is just like breathing through their nose for their first eight minutes or whatever. So when we think about a true VO2max test, we always want to be looking at the oxygen uptake. And one of the things that we can do to, because, you know, we're trying to fudge it, a lot of people are trying to fudge it with power meters, which I understand. We don't have a great VO2max modeling algorithm anywhere. You know, I would say WKO5s is probably the... Best, so far. But it's still got a pretty decent margin of error. So we're trying to fudge it, and we're trying to look at where FTP is relative to VO2 Max also. If you want to listen to a podcast on that, just go listen to the Wattstock episode, FTP versus VO2 Max, where we talk about their relationship. So the question is, I'm sure a lot of people are thinking, how Does anybody have the balls to not have a really nailed down VO2 max power and compare your FTP power to it? Well, the reason that you can do that is because you can look at your maximal oxygen uptake and then you can look at your oxygen uptake at FTP and you can compare those two numbers. That is the gold standard for measuring where is your FTP relative to your VO2 max because we are really measuring what percentage of our maximal oxygen uptake can we utilize? in a purely oxidative fashion. So what is your power of U2max really? Or your maximal aerobic power? To quote myself earlier in the episode, there is an assumption that there's a linear relationship between power output and the increase of oxygen required. But, you know, up to FTP, sure, but above it, well, let's look at it in terms of duration of several different intervals. And so to throw another monkey wrench into this whole VO2max power or for running VO2max pace, we're going to talk about another little piece of VO2max lore that you've probably heard of before. So now that we see that we kind of get messed up with the linear relationship between power output and oxygen uptake over FTP, if we look at studies, where they're looking at cycling power or running velocity at VO2max as determined by an incremental test. A lot of them look at the effectiveness of intervals that are halfway between threshold and VO2max. And so it turns out that, yeah, you can get to 100% VO2max by running under VO2max power or over it or doing a lot of other stuff, just going over FTP. You can get there for the most part. And this is... what's called the ViewToMax Slow Component. And we're going to talk a lot in detail about the slow component and its mechanism of action probably in the next episode, I guess. We'll see. So there's another study, but it's linked in the show notes, but one of the things that it looks at, it compares a three-minute all-out interval starting with an all-out sprint. On average, they're looking at like 900 watts. and they're fading to about 250 watts in the last 30 seconds. So it is a really hard three minutes. Yeah, my eyes water just looking at that graph. They looked directly at the oxygen uptake and it plateaued about a minute in and then they spent two of those three minutes at 100% VO2 max at 250 watts. Just dying. Yeah, dying. They also looked at a three minute Maximal Effort Continuous Work Interval, but it took much longer to reach 100% VO2 max in the continuous work interval. Interesting. Yeah, it was on average, I think like 30 seconds or almost a minute long or something like that. For only a three minute interval, that's a long time. Yeah, and this is a three minute maximal interval, like as hard as you can go. If you are going sub-maximally, it's going to take you longer to get there. Really, most continuous work intervals, I shouldn't say most, but a lot of continuous work intervals over FTP will get you to VO2 max eventually if you hold on to them long enough, but like ramp tests that are too long, you can also fatigue yourself before you can really get to maximal oxygen uptake if that's a goal of yours. And, you know, spoiler alert for another future episode, that's something I want my athletes to do. when we are doing VO2max work. And so this is what the slow component is of VO2max is that if you hang on to a continuous power output, your oxygen uptake is going to increase gradually as you fatigue. So is this something that could also be considered? I guess, would this be something that someone at home doing this by themselves without like a fancy measuring cart, could they identify this on their own? Like, could you watch like heart rate or something slowly creep up over the course of a three minute maximal effort as opposed to doing, you know, a three minute fly and die? Yeah, the answer is no, that you cannot. And we're going to look at another study that gets into this in some detail. So the short answer is no, heart rate is not a good indicator of VO2max, despite what certain other popular people will say. So there are some models out there, like the Adami paper that uses Critical Power and W Prime to try to find VO2max. You know, when you're a super good sprinter and having a really good anaerobic capacity, this will definitely, and without doubt, increase your Peak Value of a RAMP test or incremental test without increasing your actual VO2 max. Because we could see somebody train for like a month, not even a month, like two weeks, we can get a good anaerobic capacity increase. But without doing any VO2 max work, we can see their RAMP test improve and their actual O2 uptake not improve. A very personal example for myself is that one time in an individual pursuit, I did like 445 watts for like five minutes with an FTP of only 290 watts, which like totally ruins a lot of these ideas of like, oh, where is your sort of five-minute power in relation to your... your 20-minute power. And I certainly did not just magically gain like 50 watts of FT as awesome as that would have been. All right. So let's also think back to some of the incorrect applications that we see and try to make some conclusions around that. So here's one from my life, which is that a coach gave me intervals that were like one minute at my five-minute power intermittently through a workout. or doing other intervals, like over-unders. So it would be one minute at my five-minute power and then two minutes at tempo and then one minute at five-minute power and then two minutes at sweet spot, that kind of over-under kind of stuff. And he would say, oh, you got a lot of good VO2 Max working today. And I was like, do you know how good a sprinter I am? I was breathing through my nose that entire 20-minute interval. And he was like, well, you were working in the VO2 max zone. I was like, yeah, but it takes a while for the oxygen uptake to catch. And I've got such good anaerobic capacity that that had it covered. I think the other thing for that is you have to think like, if for that to be true your body would have to work completely in like this very binary fashion like oh he's at this this certain amount of effort therefore we immediately switch over and it turns out like nothing in biology is like an immediate switch in that sort of like very hard step function types process yeah yeah the the step functions of metabolism and biology yeah So one of the metrics that we can use for gauging whether we're at VO2max, by the way, this is a side note, is whether or not we're breathing hard. Like I just said, I was breathing through my nose for those intervals. You know, when I did actual VO2max intervals, you know, it's uncomfortable at best. Yeah. Yeah, you feel like you're drowning at worst. Yeah, it's like your breathing is really ragged. Like, you should be really, really... Feeling like your breathing is hard, like almost like it's like almost a workout for your diaphragm or something where you're actually getting in like really forced labored breathing. Yeah, your lungs burn and everything. Okay, so here's an okay application, but not a great one, but not a terrible one either. So the original Coggin training levels, your VO2 max zone, quote unquote. And this is one of the things that, you know, my, that coach of mine had over-interpreted, let's say. So 105 to 120% of FTP. So if you ride continuously there, you know, for intervals in this range, like long enough, you're probably going to get to VO2 max or pretty close. You're not guaranteed to just by being there, but that's why this is like a middle-of-the-road, like, okay application. Like, I mean, most of us, like, naturally good sprinters, good anaerobic capacity people could have told you, you know, immediately that those percentage of FTP suggestions were off and, you know, a lot of us can do way more than 120% FTP for five minutes. Yeah. I think the other thing to keep in mind with this is this is sort of derived from the sort of same sets of data. that Coggin kind of looked at this like, oh, you know, about 95% of what you can do for 20 minutes is your FTP. So like it fits this like bell curve of people. And if you happen to be outside of that middle 66% or whatever, like it's not going to work as well. Yeah, I would even say it's in the 40% who get that accurate. And I wouldn't even, you know, lay this one on Andy. I would actually put this on Hunter Allen, who's still, you know, pushing it, which is. Yeah, I mean, so I think a lot of people for a long time were doing what they thought was VO2 max work by the power numbers, but actually wasn't. And, you know, this is one of the problems, this is not in the script, but this is, it's been bugging me that this is one of the problems in a lot of studies that I see of, you know, you have to try to, like, get somebody to work out at something that's kind of sustainable where they can do intervals, but also elicits the adaptations that you want. and this is where a lot of those like the HIT studies come from. It's like they do very bad comparisons because people who actually know how to train an athlete's VO2 max, we don't give intervals like that. When we give continuous intervals, they look nothing like that. So I think that's one of the reasons that they might be popular right now but I feel like the studies are disingenuous about how VO2 max training really works. Right. So yeah, so this is like saying if you're going to compare traditional, say, five by five intervals, but you're not actually prescribing those five minutes hard enough, well, of course, you're not going to see a good increase in your VO2 max, but if you do... Don't spoil it. That's another episode. Yeah. All right. Yeah. So HAT intervals will intermittently put you at very high oxygen uptake levels. you know near and at VO2max but what I find and this is just in my experience there's not obviously a study to back this up I would love to do one someday if you want to collaborate on a study you know shoot me an email please because I don't have any of this equipment you know readily available to me so this kind of training is, in my experience, not good enough for highly trained athletes. Like, I've trained a lot of people who thought they had no room to grow, and they were like, I need somebody to help manage me to, you know, get to race day in good shape, and I'm at my peak genetic potential. And we train for a little bit, and they go, oh my god, I didn't know I had any room to grow, and like, suddenly I've got 20 more watts? It's like, yeah, you weren't training effectively before. So these studies... you know they compare intervals that are poorly designed to elicit improvements either by like some dumb percentage of like W max from a ramp test or like by matched RPE or matching kilojoules work or like rest periods like very strange stuff like that where you know if you're going to design things you know you want to compare apples to apples not like apples to like Applesauce. I think it's like apples to pineapples. Actually, it's even better. Yeah. Yeah, you don't want to compare apples to pineapples. Yeah. So far, we've just looked at ramp tests and intervals and stuff. So let's now take a deeper look at maximal aerobic power, you know, power at VO2 max. But we're going to look at some of the resources that are readily available. And, you know, they're going to tell you that, and by the way, every lab has a different ramp test protocol that they use, the same one on everybody for the most part, unless you see somebody designed it so that somebody would land in the, you know, 8 to 12 minute range. So they'll tell you that your maximal aerobic power or your power of VO2 max is the power of your last stage of a ramp test. or it's the last average 30 seconds of a smooth ramp test, not a step test, or the highest average one minute power regardless of smooth ramp or step. And there's a lot of ways to try to get this because obviously if you go like 30 seconds into your last one minute stage, you know, is that your VitaMax power? You know, what's the deal here? So there's always a fudge factor when, you know, you've got something that's, you know, imprecise on its foundations. So, but we just saw that ramp rate and anaerobic capacity will change this final power value. And this means it's not a true maximal aerobic power. So a true maximal aerobic power would be defined as the maximal power output from only oxygen-derived ATP. And this is going to be over a threshold, so we cannot separate that out from a single ramp test. And, you know, even the Pinot and Grappin paper, recognizes this. Quote, there is no common procedure that would determine maximal aerobic power since it is dependent on the test protocol in laboratory and field. Interesting. So they even admit that it's not a... It's not a... Concrete Number. Well, their model is looking at your Mean Max Power Curve, and they use a lot of world tour cyclists whose power curves look a little different than a lot of ours. So we're going to talk about that another time. I'm working on an improvement to that model as we speak. So basically, this is one of those things that appears in the literature and that there are reference to in other things, but It's like a game of telephone that's been happening since 1923, and now nobody agrees on anything. So there's a lot of references to older papers that also rely on the additional criteria to ensure a maximal test, like blood lactate and RER and things like that. Or they have flaws in a premise, or they have flaws in their methodology that at the time we understand why they would have made those assumptions, certainly. saying they were bad scientists. They were great scientists at the time and they were doing the best with the knowledge they have now. Yeah, they were limited in their ability. Yeah, and we are doing the best with the knowledge we have now and we know a lot more. And so, you know, it's not like in physics where, you know, your first physics class is stuff that they've been doing since the 1600s. Yeah, exactly. Or earlier. But I think that's what's also great about science is that we can change our minds with the new information and deeper understanding that we get. from the iterative nature of science. Definitely. Oh, for sure. That's, you know. Yeah. But also, like, here's one of the other things that bugs me about some folks' perception of what's in the scientific literature right now. That if something's been published in a peer-reviewed paper, that makes it gospel. Right. Like, there are problems in the critical power model. I'm not going to say it's not useful. We talked about it a little while ago in a space where it was useful. But just because it's been in a lot of papers does not mean that it is an actual, physical, irrevocable fact because there are definitely assumptions in the critical power model that make no physiological sense. And we got into that in the FTP versus critical power episode. So you can go check that out if you have not heard it yet. So the thing that bugs me the most about ramp tests and maximal aerobic power, my honest thought on this is please run far, okay, please ride far, far away from these. Cyclists, we're not good at running. Well, it's because that like, again, with the FTP thing, they're assuming that there's a linear relationship between You know, between everything, and they're not looking at the actual, like, fatigue point, which is FTP. You know, above FTP, you fatigue faster, below FTP, you fatigue slower. It's very simple. It's very simple. And, you know, the assumption in the training zones based on maximal aerobic power doesn't include that, and it should, because that's a point that can vary, and maximal aerobic power can vary. We've been over this. Anyway, so... The other thing is that reverse calculation of your oxygen consumption in liters from power numbers, all of these are suspect. So that's like, for example, your Garmin will spit out a VO2 max estimate based on rides and... How does it arrive at those numbers? Like, it just looks at the power that you were doing and then spits out a magic number, sort of like a black box. You can find the formula for this. Yeah, and Garmin's estimates of everything are some of the, next to Whoop, I would say, are some of the most cringeworthy numbers I've seen yet. I'm sorry for people who love Whoop. Yeah, so anyway, so it's because of the fundamental, we're going to bring it all the way back right now. So it's because of the fundamental flaw in the original assumptions that Hill and Lupton made. But they didn't know at the time, you know, they were assuming that the work up to exhaustion was fully aerobic. And that's where all of this misunderstanding has come from. And there's, you know, there's a handful of us who are, you know, doing what we can to shout about it. Hi. Cycling is a sport of tradition, like a lot of things, like cars and houses and architecture. It's hard to break the old mold. And every sport has their lore or their culture that is just unstoppable sometimes. Yeah, so I think this is all to sort of bring it back and say that this Maximal aerobic power or this number that you get out of this ramp test may not actually be your power output when working at your VO2 max and also that the power output that you have when working at your VO2 max is not necessarily a well-defined quantity and some of that has to do with the testing, some of that has to do with the ways that your body actually functions and the different ways you can make your body Function at VO2max. So yeah, so this is, it's kind of this very murky, you know, bag of wrenches, I guess, of what is actually your power at VO2max. But I guess this isn't necessarily to say that that number that you get out of maximal aerobic power isn't useful in some way, or that the mean max power for those three minute maximal steady intervals isn't useful. but it's to just immediately jump and say oh I did this for four minutes therefore my VO2 max is why that is not a good don't trust your Garmin when it tells you that it's not a good assumption but certainly tracking something like three to five minute mean max power is is useful and you know you can sort of decouple that from claiming that that is your VO2 max or something like that yeah still track and still track improvements in this range because it turns out it's a very useful range for lots of racing. Yeah, definitely. And it's even a good range for testing, honestly. Like if you control somebody's anaerobic training while you're training VO2 Max, you can pretty reliably use like five to eight minute power as a good substitute. You can also, Andy Coggin also had a really good blog article a long time ago on how you can look at quote-unquote VO2 max power through a short maximal test. And you start really hard and then the power will drop and then it will plateau supposedly right at your VO2 max power. So while this method might look good on paper, the fact is that it's not good enough. So my personal standard for a test for a physiologic value is going to be that it 100% of the time or at least 99% of the time gets within about 5 watts of the thing that we really want to see. And does this test do that? The answer is unfortunately no because it has a built-in assumption about how muscles work that is actually not the case. So the built-in assumption is that muscles are working uniformly, that you are using all of the available muscle mass and that you are burning off all of the available anaerobic capacity. And what happens is, for instance, when somebody is really, really fresh, their larger motor units, as you get into this test, as you look for that plateauing value, you are recruiting larger and larger motor units that have more anaerobic capacity and one more than the last. This is the problem is that you are now still utilizing anaerobic power as you go into this test. And so you are not only using your fully, your 100% aerobic power, aerobic derived power, you are also continuing to use anaerobic power. And one of the... One of the problems that can really screw us up with training our anaerobic power in addition to VO2 max, if we fold in a bunch of stuff into a training cycle all at once, we are going to be even more training our larger motor units to have more anaerobic capacity, and then this is really going to further screw us up. And this is one of the things that both Kyle and I have found, is that doing these big efforts, doing these big tests, when we're really fresh, we're good sprinters, We have way more supposedly maximal aerobic power than we actually do because of this principle, because we have really highly anaerobically trained large motor units. And this is what screws us up. And this can screw you up if you are building an entire model or a training philosophy around this one thing that has a Real complication to it. Like for instance, Inside does their VO2max power testing like this. Then if you start to build a model on this, now you have, you know, a real big error propagation going throughout the entire thing. So when people use this type of power test or any kind of maximal aerobic power test in their daily life, and I think the most common one would be looking at where is your FTP relative to your VO2 max. Now, using this to just track this very simple thing or any maximal aerobic power test, you know, you are going to be, you're always going to have to Be wondering, you know, where does this power really come from? How fresh was I? And there's that problem that, you know, we don't really know 100% that it was truly aerobically derived. Now, having said all that, there is something to this that is true and valid in Andy's testing method of looking for that plateau in a pursuit-type effort. However, I'm not going to get into it right now because it is a trade secret and it's something that I've used for a long time to really track somebody's VO2 max. So while this episode is going to end in a mystery, unfortunately, well, fortunately for my athletes, we're using this. Not that I've told any of my athletes, so you can't ask them, because they don't know how I do this. So I can't leave you guys with that, though, can I? So let's look at what can we do practically. So practically to keep track of VO2 Max, I'm not going to say that this is going to keep track of true VO2 Max power, because, you know, as I've said, I think pretty clearly in this episode, I don't think we really can. determine that, at least not in the way that most people think, although I think my personal method to track it is pretty good. So here's the other way that I track it, because obviously just relying on one thing is not as good as triangulating with several things. So I do the same thing everybody else does, which is a five-minute test. And with the five-minute test, I'm not looking for a plateau. I'm just looking at the average power between two five-minute tests. And the only thing that I want to know is in between those two five-minute tests, which are obviously in the same condition of freshness, the only thing I want between those two things is VO2max training, only aerobic training. Because if we start doing anything that has anything to do with anaerobic capacity, you know, in a lot of people, anaerobic capacity can get built very quickly. and we want to control for that. So that's how I do it is I compare two five-minute tests, just the average power and I make sure that we've controlled for the other variables as much as we can and between that and my other method of tracking view to max, it actually is really good. I think that goes to even speak generally if you're going to test and test for some number. You're going to want to keep the testing protocol the same every time, and so it's at least comparable relative from one test result to another. Those test results may not be comparable to some absolute measure like milliliters per kilogram per minute, but it's still going to be a useful metric. within your sort of relative range. Right, exactly. And I'm sure, you know, there are even dietary considerations for this as well, you know, because if you are, you know, under fueled going into a test, you know, you are 100% reliant on carbohydrates at that point. And, you know, it's just going to be, it's going to affect your test value. And, you know, you might be able to get to the same oxygen consumption, but it's going to also affect the power output at which you get there. You can have a rigorous and standardized test for you if that works for you and your training philosophy. I'm not saying you shouldn't. I really want to just present information and then you can make your own decisions. I hope I've done a good job of making that pretty clear. But to me, there's no such thing as real power output at VO2max. We really want to look at actual liters of oxygen. At least to me, anybody who says differently than that either doesn't have the same understanding that you now have or they're selling something. So anyway, I hope everyone enjoyed today's episode and gets a little deeper insight into where this VO2max stuff comes from and also why the waters are very murky when people talk about what is VO2max power and maximal aerobic power and all these things and hopefully that can Start to better inform your training or training for your athletes and things like that. Yeah. And so, as always, I want to thank everybody for listening. You guys are the best. I love all of the comments and emails and messages that I get saying, how much people have improved their FTPs since implementing some of the tips that we've given for FTP training. That is great. So feel free to share those success stories with me. We love to see them. And please subscribe again if you have not and share the podcast. If you want to help your friends' FTPs, send them all the FTP episodes. Give us a good rating, a nice review. Yeah, iTunes reviews and ratings go a very long way. We're up to... something like 50, over 50 five-star reviews and a bunch of really nice reviews and it means the world to us when we see those kinds of things and remember that we're ad-free also so if you want to donate and support the show you can do so at empiricalcycling.com slash donate we have the show notes on the website all of the studies that we talked about are linked there and if you have any coaching or consultation inquiries questions or comments you can please email empiricalcycling at gmail.com and with that we will see you guys all next time thanks everyone Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio, Fabio