How to Make VO2max Workouts and Threshold Workouts Work for You, with Hunter Allen

We explore the best ways for endurance athletes to do VO2max workouts and threshold workouts with cycling coach Hunter Allen.

Man in yellow cycling jersey riding a road bike during a VO2max workout.

Tabatas, over-unders, and sprints are just a few of the most popular types of interval workouts that have received a lot of attention for the gains they offer. But if there are two types of interval workouts that might be considered the go-to workouts of endurance athletes, it would be threshold workouts and the dreaded VO2max workout. In this episode of Fast Talk, we explore how to execute these workouts with cycling coach Hunter Allen.

At first glance, threshold and VO2max workouts can appear similar. For example, our popular 5×5-minute intervals can be used to train either. Crank up the watts with a longer 5 to 10-minute rest between efforts and you have a classic VO2max workout. But, with lower watts and a one-minute rest, you’re then looking at more of a threshold workout.  

Understanding the differences between the two—and how to best execute them—is very important. Helping us break this down in our latest show is legendary coach Hunter Allen, author of Training and Racing with a Power Meter, co-developer of the TrainingPeaks software, and founder of Peaks Coaching Group. Allen has used threshold and VO2max intervals with athletes from beginners to top pros. He shares his experience with us on what he’s found to be most effective. He also talks to us about Project Fuerza, which uses the power files of pro riders to create NFT artwork.  

Hunter Allen (pictured above) joins us to talk about threshold and VO2 max workouts.

Along with Allen, we’ll hear from Dr. Stephen Seiler, a friend of the show and world-renowned researcher from the University of Agder in Norway. We’ll also hear from Brent Bookwalter, a retired World Tour rider who now invests his time with the Pro Cyclists Foundation charity. Finally, we’ll hear from Dr. Robert Kenefick, a researcher at Entrinsic Bioscience.   

So, decide if you want to deeply suffer for just a couple of minutes or suffer for a longer time—and let’s make you fast! 


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Episode Transcript

Rob Pickels  00:04

Hello and welcome to Fast Talk, your source for the science of endurance performance. I’m your host, Rob Pickels here with Coach Connor.  Tabatas, over-unders, and sprint intervals are just a few of the intervals that have received a lot of attention for the gains they offer. But if there’s two types of intervals that might be considered the go-to workouts of endurance athletes, it would be threshold intervals and the dreaded VO2 max intervals. At the surface, threshold and VO2 max intervals can appear similar. For example, our popular 5 x 5-minute intervals can be used to train either. Crank up the watts with a longer 5 to 10-minute rest between efforts and you have a classic VO2 max workout. But lower the watts and a one-minute rest, and you have a threshold workout. Understanding the differences, what each type of interval trains, and how to best execute them is very important. Helping us break this down today is legendary coach Hunter Allen, author of Training and Racing with a Power Meter, co-developer of the TrainingPeaks software, and founder of Peaks Coaching Group. Allen has used threshold and VO2 Max intervals with athletes from beginners to top pros. He shares his experience with us on what he’s found to be most effective. He also talks to us about Project Fuerza, which uses the power files of pro riders to create NFT artwork. Along with Allen, we’ll hear from Dr. Stephen Seiler, a friend of the show and world-renowned researcher from the University of Agder in Norway. We’ll also hear from a retired World Tour rider who now invests his time with the Pro Cyclists Foundation charity. Finally, we will hear from Dr. Robert Kenefick, a researcher at Intrinsic Bioscience. So, decide if you want to deeply suffer for just a couple of minutes, or suffer for a longer time—and let’s make you fast!


Trevor Connor  01:55

Listeners, this month, we’ve opened up 12 of our best members only guides just for you, and it’s free. Join now at our free listener membership level and enjoy our deep dives into intervals.ICU, Dr. Stephen Seiler’s famous 4 X 8-minute intervals, TrainingPeaks performance management chart, 5 X 5-minute interval analysis, or guides to VO2 Max & lactate testing, and much more. Become a listener member at  Well, welcome Hunter excited to have you back on the show. And right before we got on the recording here, you were telling us about your new business, Fuerza, and you mentioned NFT’s to which I kind of went, “Oh, what’s that?” And you started showing us these images and they were fantastic. So tell us a little bit about this new adventure of yours.


Hunter Allen  02:47

Well, thank you. Yeah, no, I’ve been really excited. I’ve been working on this for a while now. And what I’ve done is I’ve signed about 25 pro riders both retired and current. So big names Peter Segan, and Mark Cavendish, Aaron Thomas Jens Voigt, Mark riders who are really fantastic world champions and France type guys. And then we’ve taken their wins and Tour de France, World Championships, Parer Bay, everywhere, I’ve made analyze that data because this you know, I’ve spent 20 years analyzing power data, look for the best parts of them, you know, like some amazing sprints from Mark Cavendish, etc. And then I’ve got seven artists who then I get those pieces of data to them and then they create this incredible piece of art, which has just been fantastic. And we have kind of two categories where one is it’s a, it’s a piece of art, for example, you know, it’s this mountain scene, and then the data is embedded in it. Or we also have another category where the data is the art, you know? It’s hard to imagine on this without seeing them, but it’s really neat to see how these artists come up with that. So not only when you buy a Fuerza, do you get the piece of art. And you can imagine a future right where you walk in your house and you have LCD screens on your wall. And you know, instead of paintings, you just have LCD screens and you can move the pieces of art around in your house, you can sell them if you want to, you can buy a new one. I mean that future is coming. So you know, when you buy this piece of art in Fuerza, then you also get the power data file. So if you wanted to see Peter Segan’s, when in the World Championships 2015, when he won in Richmond, Virginia, we’ve got that Fuerza. And you get that power file, you get a license to view it, analyze it, download it, and then when you resell it, you re-upload it and you can resell that piece of art as well. So these are great, could be great investments. And then same time NFT’s which stands for non fungible tokens, these can be tickets to experiences. So for example, the certain price point is reached, you get a zoom call with Mark Cavendish for an hour. Or maybe you get to go for a private two day weekend riding with Garen Thomas. So all those things we kind of creating and project were.


Rob Pickels  05:27

Well, Hunter, I wish you success with this because I’m pretty sure the value of my crypto portfolio is riding on whether or not you’re successful in this business. So, good luck for all of us out there listening, we are behind you, 100%.


Hunter Allen  05:42

Well, thank you.


Trevor Connor  05:43

I’m just still trying to get over the $12 million Sargon painting. Not sure I quite have that money.


Hunter Allen  05:52

It was $10 million on Monday, but if yours has gone up, it’s $12 million now, so somebody should have bought it on Monday and they would have made 2 million


Trevor Connor  06:02

For that sort of money, I don’t just want to ride with Sargon, I want his legs.


Rob Pickels  06:07

Can we just go ahead and cut those off and glue them on over here? That’d be great.


Trevor Connor  06:14

All right. Well, let’s dive into this episode, which is one I have been really excited to do. Because this is getting into the nuts and bolts of training. We have had a lot of our listeners reach out to us about what are threshold intervals? What are VO2 max intervals. We had Sebastian Weber on the show, who, as soon as we mentioned VO2 max intervals, he was like, “What are those? Why do you use that to him?” Yeah, that’s my horrible attempt at an accent.


Rob Pickels  06:42

A little, Arnold Schwarzenegger. A little, yeah.


Trevor Connor  06:44

I think I covered every country in Europe at some point in that accent.


Rob Pickels  06:48

The Irish are very offended right now.


Trevor Connor  06:51

But, I think it’s a really good conversation to have because these are two very common forms of intervals. I think there’s a lot of misconceptions about them. And I think it would really help everybody to hear what are the best ways to execute this. And Hunter, I don’t think we could have a better person on the show to talk about the nuts and bolts of two of the most popular forms of intervals.


Hunter Allen  07:15

Thank you, thank you Trevor. It is a great topic. And I think also one that, you know, like you said, there is some misconceptions about it. People don’t quite understand, you know, these two different concepts. So yeah, let’s see if we can get through and help out folks who give them a clear understanding of both things.

Difference Between Threshold Intervals and VO2 Max Intervals

Trevor Connor  07:39

All right. So let’s start with the obvious question. What is the difference between threshold intervals and VO2 max intervals?


Hunter Allen  07:46

No, that’s great question, Trevor. You know, I think that’s something we need to first define. What is threshold? When we talk about that and then we’ll also define VO2 max and we can go from there. So first off, when we talk about threshold, when I’m speaking about it, I’m thinking about the functional threshold power. Alright, so functional threshold power (FTP) this is a definition that Dr. Coggan and I came up with back in oh, I think it’s been 20 years ago now. 2002, I believe, and we defined it as the highest average power you can maintain in a quasi steady state without fatiguing. Now, that’s been the same definition for 20 years. And so, it’s always been that definition, it hasn’t changed. But practically, what does that mean? Well, that means that the highest average power you can maintain for around 60 minutes. It doesn’t have to be exactly 60 minutes, it could be 56 minutes, it could be 58 minutes, you kind of have that, you know, idea of understanding that I’m riding my best, on the limit, on the edge for now. Now, the problem with that is, that if you don’t have a place to do an hour of ride at your FTP, you don’t have a climb, you don’t have a flat road, you’re in city traffic, etc. Or maybe you don’t want to do that on your trainer for an hour. So I came up with the shortcut it’s  the 20 minute effort, the 20 minute test, and most people have forgotten about the 20 minute test. And the fact that they’ve forgotten to do the five minute test before it, you have to pre fatigue those muscles a little bit and get rid of the anaerobic capacity, the anaerobic work capacity to get rid of some of your freshness. So, if you do the five minute test before, then you do a 20 minute test, you subtract 5% from your average power of the 20 minute test, and it gives you a close approximation of what you could do for the 60 minutes. Now it may not be exactly right, you know? But again, if really wanna know your FTP, go man up, put your big boy pants on, big girl pants on, and do a 60 minute FTP test. Now, that’s FTP. Let’s talk about VO2 Max and how that is. And so VO2 max really is simply defined as the volume of oxygen that you can bring into your lungs, and then take that oxygen, get it into the red blood cells, through the heart in training and making that transfer happen back into the arterial blood flow. So you can get it back to the working muscles which need that highly oxygenated blood. Now, VO2 Max is talked about in a couple of different terms. So most people have heard them in two different ways. They’ve either heard them as a number between zero and 100. And that is really defined as the milliliters per minute per kilogram of body weight. So for example, you know, some of the best riders in the world, they’re going to have a 90 milliliters per minute per kilogram of body weight. You’ve also heard it as liters per minutes. And that same rider that as a 90 milliliter per minute per kilogram, might have a little over a six liter per minute measure of their beauty Max. In general, we talk about the number, the milliliters per minute per kilogram. So hey, what’s your VO2 max? My max? Oh, I’ve got a 55 or I’ve got a 70 or whatever. And that seems to be kind of the common nomenclature. So hopefully that clears up, what are these two different things, we got threshold and we’ve got VO2 max. And Trevor the other thing that’s really important to know is, you know, these things are continual. So when you’re doing FTP, you’re using, you know, lung capacity, right? You’re maybe not at your VO2 max, but you’re using a percentage or your VO2 max.


Trevor Connor  11:56

Yeah and actually, so I was digging through to find some research that compare these two, which was was actually somewhat difficult. But I found one study, actually it was a lactate threshold concepts, how valid are they by Dr. Foud. And in there, they raise this is a continuum. It’s not a, you know, threshold you’re completely training one energy system and then when you get to VO2 max, you’re completely training a different energy system. Even when you’re at that threshold at your FTP, you’re bringing in both aerobic metabolism and you’re bringing in anaerobic metabolism. In some ways the difference as you get to that VO2 max is you have now, as the name implies, maximize your aerobic contribution, so you’re bringing in a little more anaerobic power. But it’s not night and day. I think another really important thing to mention is it’s generally agreed that the power that you hit at VO2 max in a VO2 max test. That’s the power that you can hold for about four to six minutes.


Hunter Allen  13:03

Yep, exactly. And so that’s a great point, right? Because when we think about that as a, and I actually kind of define it a little bit wider than that, three to eight minutes, but it is something in that range. And again, that’s kind of like that depends on your ability, your anaerobic ability. And so that’s really something that you continue to do and think about and understand. But we know that FTP, we know that functional threshold power is a 60 minute effort. We know the VO2 max kind of range again from the three to eight minutes. So then that brings us to this second part of your question to answer that first question really is like, what’s the difference between those two different intervals? So if I’m going to go do FTP intervals, if I’m going to ride my threshold, I need to ride in between 91% and 105% of my FTP, I need to do it for a minimum of 10 minutes. If you do really, if you do these intervals for less than 10 minutes, you’re just not creating enough training stress in order for you to really make significant adaptations. To give the body enough strengths to adapt from. So we need to do at least 10 minutes, you know, and I would say more like, well, let’s do 4 x 10 minutes, let’s do 3 X 10 minutes, let’s do 2 X 10 minutes, let’s do 5 X, etc. Or maybe you do 4 X 15 minutes, or 2 X 20 minutes at your FTP, at 100%, or 105%, or even 95%, we’re training our FTP. So when we do a VO2 max interval, then now we’re riding for that 3-8 minute range. And we could be from 106% of our FTP up to 150% of our FTP, depending on how big your VO2 max is. The bigger your VO2 max, the higher that percentage might be that you can ride out. So we’re now doing 7 X 3 minutes at maybe 120% of your FTP. Maybe we’re doing 5 X 5 minutes at 115% of your FTP. So that’s really kind of the difference between the two is looking at the percentage of your FTP that you’re riding at, the length of time, and FTP versus VO2 max.


Trevor Connor  15:24

Hunter just talked about how to determine your FTP and how it’s your one hour power. But let’s hear from somebody else. Here’s Dr. Steven Seiler and his thoughts on doing a one hour test.


Dr. Stephen Seiler  15:35

Typical American, you know? A lot of people will just say, “Ah man an hour, that’s just too hard. Let’s do it for 30 minutes or let’s do it for 20, or what about eight?” And so things have just kind of slipped in typical American fashion, it seems the original intent has kind of been lost. So I think Andy would agree that an hour is a good test, because that’s what he was doing back in the day. There’s even a kind of a traditional component to it, you know? The hour is just part of cycling. So it really, it’s really an anchor point in understanding your ability to perform in races and so forth. And so I find it to be just a fairly, you can make an argument for it physiologically, and you can also make an argument for it just traditionally, and, you know, it’s a good calibration for for athletes. Then there’s no argument about well, you know, “Is .95 right? Or should it be .9 X 20 minutes? Or you know, just do the hour? And if people do that, then they will, they’ll know where they’re at.


Trevor Connor  16:44

So going back, what might be a misconception, and I’m very interested in hearing your answer to this. But, are threshold and VO2 max intervals named that way because they train your threshold and your VO2 max, or are they named that way because you’re doing work at those intensities? And I can tell you, my answer is a bit of column A, a bit of column B, but Hunter, how would you answer this?


Hunter Allen  17:11

Yeah, that’s a that’s a great question. Really great question. And I think that deserves a really good answer as well. And so when we think about it, what is the, you know, threshold? We think about it from a perspective of, okay, I’m riding right at my limits, okay? So I like to use the kind of, the way to help people understand this is, you know, think about your threshold, your functional threshold power as a table, right? You’ve got a table in front of you, it takes an hour to go from one side of the table to the other side of the table. And that is the same hour for me, for Gareth Thomas, for you, for Pure Sargon, whoever it is, it takes now. The difference is the height of the table. When you first start out in cycling your tables down near the floor. All right, your FTP is really low, okay. And then as you get fitter, and fitter and fitter the table gets taller and taller and taller, and the legs get longer. And eventually, maybe you get so high, you’re at the ceiling of your FTP, and you’re racing the Tour de France. Now, how do you pick up a table, right? And this is kind of a reason to kind of think about we how we improve our FTP and I know we’re gonna get there in a minute. But this might help folks to kind of visualize this idea. Well, you’re not Spider Man, you can’t put your hands on the table and actually cut the table top up, right? That’d be sweet if you can do that, but you can’t. So you really put your hands underneath the edge of the table, underneath the lip of the table, and you push it up from just underneath the edge. Okay, so we talk about that a lot from idea of sweet spot training. You know training between 88, 93, 95% of your FTP, just underneath your FTP. That’s how we push the table up from underneath. Now, I can take my fingernails and stick it in the edge of the table and lift that table up, right? That is painful, right? That’s riding at the edge, that’s riding at your limit, that’s riding at your FTP, okay? So, back to kind of the question, I think of it as a practical definition, because it’s functional, right? You’re out there on your bike, you’re not some lab somewhere, you know, you’re measuring power. We’re not measuring lactate, we’re measuring, you know, you’re not measuring your cadence or anything. We’re measuring power so it’s Functional Threshold Power. So, from that perspective, is that if we were defining threshold as your lactate threshold, okay, we’re looking at the lactate levels in your blood, right? We’re defining those things. What are you training? Well, you’re training the ability to ride, buffer, lactate, buffer all of the positive hydrogen ions, all those things that prevent you from going farther and faster. And so those are the things that we’re training. When we think about VO2 max, we think about it from a perspective of, okay, this is the volume of oxygen I can take into my lungs, the size of my lungs. And when we train that, are we really training our VO2 max? Well, doing intervals at VO2 max, if you’re untrained, can help you increase your power numbers at VO2 max? Does it really increase your VO2 max once you’re highly trained? Not really. I know I talked about it as it increases your speed, your ability to go faster at VO2 max. So there’s a bit of both, like you said Trevor, a little bit of both.


Trevor Connor  20:58

I love your analogy and you brought up the important point. We’ll get into this when we talk more about threshold intervals, but the goal with them isn’t always to go as hard as you can go. As matter of fact, a lot of top athletes, when they’re training that lactate clearance, when they’re trying to raise their threshold, are actually training a little bit below. But yeah, I agree with you on the the VO2 max, I was looking for studies last couple days on VO2 max intervals. And some said, “Yeah, we see improvements in VO2 max.” The other said, “We saw none.” And that’s where you really have to look at the methodology. And what you see is the ones that saw improvement, well they were using typical college students who weren’t necessarily that fit. Or the ones who saw no improvement were using much fitter athletes. And my argument is, you take somebody off the couch, yeah, you’re gonna see improvements in VO2 max. And frankly, almost any intervals are going to improve their VO2 max. But I think once somebody’s at a certain level, you’re going to see gains from doing training at that intensity, but it’s not necessarily going to bring your VO2 max up.


Rob Pickels  22:04

I think at the same time, I don’t know that we should have a reliance on these individual physiological variables because VO2 max is a determinant of performance. It plays into a limitation that could be affecting how fast, how far you can run a ride. But for me, ultimately it is the power at VO2 max, it is time trial intensity, or completion duration. Those performance aspects are what I think that we ought to be hanging our hat on. Maybe moving away from some of these lab variables a little bit when we’re determining if something is effective or not. If you go the exact same workload, but it takes you 10 milliliters more oxygen to do it, did you get better? I’d say you got worse.


Hunter Allen  22:49

Right. And so I think that you have to kind of wrap your head around the idea of what we’ve created as a way to make it simple. How do I know that I’m training this system, this energy system? And so I think the overall alliance on these terms and things and this physiological soup, you know, it can create confusion, for sure. But we also have to remember that like, wow, I want to you know, what do we all want? I want to be a faster cyclist, right? Period. I want to ride my bike faster, right? And so how do we do that? And how do we guarantee that we’re doing that? Because before we have power meters? We didn’t know. He was like, “Well, I’m gonna go and do intervals and then I’m going to do five minutes musket heart rate at 175.” Okay, well is that good? Is that bad? Did you have a lot of caffeine today? Did you not sleep good last night, you know? Is it really hot outside? So they didn’t really know if we were actually training our threshold that day, our Functional Threshold Power. Or we didn’t know if we were training or anaerobic capacity, or we are training our VO2 max measurement. Really no idea in from that perspective because we didn’t have the right tools. So with a power meter now you can say, Okay, well, I don’t want to say 100% guarantee, but I want to say pretty damn close, 98 99% guarantee that you’re riding at 115% of your FTP, you’re probably stressing your VO2 system. And that I think, you’re doing it for five minutes, you’re creating enough training stress, that you’re going to adapt and get stronger from it. Again, you can’t just do it five minutes, once a week, you got to do 5 X 5 minutes or something. So as long as you keep that in mind.

Execution of VO2 Max Intervals

Trevor Connor  24:44

So that really brings us to the execution. And I think it’s really important to talk about what are the best way to do VO2 max intervals. Because you just mentioned the classic mode, which is the 5 X 5 minute intervals and the one counter I’ll give you is, if you do the 5 X 5 minutes, you don’t need power, heart rate, and anything. There’s a real easy metric. If you’re throwing up at the end of every five minute interval, you did it right. But that’s my concern, because you do five minutes at that VO2 max power, it hurts like you wouldn’t believe. I mean, I do that and I’m gasping for air for the next two minutes. The thought of doing five of those in a row. I’m not sure how many times you could get me to do that. But that’s my question for you, Hunter. When you’re working with athletes, and you’re saying I’m going to give you VO2 max intervals, do you go with the classic five by five? Or do you go with something else?


Hunter Allen  25:37

Right, you nail it right on the head in the way you describe it too. I think that everybody who’s listening needs to understand that as well. You know you’re at your VO2 max when you are painting, right? You are not breathing in rhythm. And when I’m in rhythm, I’m in my FTP. I’m breathing really hard. I’m in rhythm and I’m maintaining that rhythm. It’s at the top end of my ventilation threshold at that rhythm, right? But then all sudden, when you go to VO2 max, now you’re just, you’re dying, right? You’re not in rhythm, you’re about to explode at any seconds, and it hurts. So that’s a great way to confirm you’re kind of, you know, responses, right? Because that’s what it is, breathing raise response to the power you’re creating, that you’re in your VO2 max. And I agree, it hurts, it’s tough, it’s not easy. I make sure that when I prescribe these types of intervals, we generally only do one VO2 max session per week. And it may just be okay, ride out, warm up, do 5 X 5 at 115% of your FTP or 112 or whatever the athlete needs. Then rest for five minutes in between each one and ride back home. That may be all they do. Or maybe it’s part of a different workout and they do a four hour workout, or a two hour workout, or a three hour workout. And they’re doing the 5 X 5 in the first hour. And then after that, now we’re doing sweet spot work because we can still do sweet spot work. Or maybe we’re just riding it tempo. So that way you’re getting that most intense interval done first, which we know is a solid concept that we always want to do. But it is challenging, right? And I limit the amount of total work to 25 minutes. So if it’s 5 X 5, that’s it. If it’s 7 X 3 minutes, that’s 21. Okay, we can do 8 X 3 minutes, that’s 24. So I try and limit that total work time to 25 minutes, once a week in a dedicated session. Now we might do a couple of VO2 max intervals on Saturday or something. So we might get some additional work there. But in one session I limit it to that.


Trevor Connor  28:06

So what about, and I’ll admit, this is often what I do with my athletes, I’m very careful about giving those those five by fives because of how difficult they are. What about doing shorter intervals of VO2 max power? Like doing a two minute or a three minute interval, but having a shorter recovery, so that aerobic system stays ramped up.

Anaerobic Ability

Hunter Allen  28:25

I think when you start to get to the two minute range, you’re starting to reach into the anaerobic ability of some of the athletes. And so I think at that point, it’s not long enough to really engage the aerobic system enough to create that training stress you want. But I think the minimum is really three minutes that you should do, especially if you have a strong anaerobic ability. Many of us have that, just need to make sure that, oh wow, we’re pacing ourselves. And I’ll talk about that and say, look, when you do VO2 max intervals, you have to pace yourself so that you’re not just finishing and you know, you started out and your watts were at 300 and you finish your watts at 200. You know, you’re starting out and you’re saying okay, I’m going to hold 280 and then at the very end, I’m going to punch it to 300 for the last 30 seconds to maximize the VO2 max portion of it. Now you’re doing a two minute or one minute interval, those are pretty much all out, die 1000 deaths in the last 30 seconds. So I think that’s important.


Trevor Connor  29:32

Yeah, and to your point, I’m going to bring some of the research in today. I did find some of the classic interval studies and I’m looking at one right now by Stepto from 1999. And this is medical, science, sports, and exercise journal, and we’ll put all these references on the website. It compared 30 seconds, to one minute, to two minute, to four minute, to eight minute intervals and showed that there was this curvilinear relationship where we’re really seeing the biggest gains in that three to six minute range to your point.


Rob Pickels  30:03

Trevor, can I ask in that study, what was the restorations as you go through those? And the reason that I bring that up is there has been shown to be a high sustained level of oxygen consumption with short intervals, if there’s also a short rest interval as well. So, you know, this is the theory behind the Tabatas or you know, being a 22nd on 10 second rest. And maybe more commonly for cyclists 30 30s in that range as well. And I believe it was Dr. Seiler, that kind of likened 30 30 workout to more of a, almost like a steady state workout with fluctuating power. Because the rest interval was so short, you don’t have time, or actually if I remember, that was in reference to 40 seconds on 20 seconds off, because you don’t have time for that oxygen utilization to come down in such a short rest interval.


Trevor Connor  30:54

Well, there’s a bunch of studies on five by five minute intervals with one minute recoveries, because even though it’s five minutes, and you would think that’s a VO2 max interval. With that shorter recovery, it tends to actually be more of a threshold interval. It’s like doing a 25 minute threshold effort.


Hunter Allen  31:10

Rob you’re exactly right. I mean that’s why Dr. Coggan came up with normalized power because we needed to make sure that we understood, what did the body really feel like, if you went up a hill? That was a three minute long hill and then you went down a 10 second, or 15, second, you know, on the downhill, and then went back up three minutes again, you know, what were you really training, when you look at the average power of course the zeros are included in that. So your average power if you held 300 watts in the uphills, you know, and zero watts on that 10-15, second downhill, your average power is gonna be 295 or 294 or whatever it is. But if you look at the normalized power, it’s gonna be right at 300 watts because that’s what your body didn’t have time enough to recover. And then normalized power goes on 30 second rolling average, which 30 seconds is fairly, you know, not unique, but it’s just kind of unusual or whatever. There’s lots of things that have 30 second recovery restoration rates in the body, lactate recovers a three second half light, heart rate does a 30 seconds as well. So you know, those are the things where if you do that, then you’re still making it through it. Now, I’ll tell you one story that I think is important to kind of make sure you’re being careful with this is that I once had an athlete, very good athlete, category one cyclists, he could crush criteriums, he would come in an hour long criteria, and you’d be in the breakaway might even win the race, his normalized power at the end of the race might be 360 watts. And in general, when we see an hour hard race, and then we can take that normalized power and say “You know, that’s pretty close to what your FTP would be.” So then, on Tuesdays, he had a local time trial, 10 mile time trial that he did. And so I was like, “Okay well, your FTP is 360, 350, let’s be 350, let’s hold 350. We’ll give you a little bit of the benefit of doubt here, we’ll be able to serve.” Well, he would struggle to do 300 watts for that 10 mile time trial. Struggle, couldn’t do it, you know. At the end of the thing and be like, “What is going on?” You know, and he’s like, “I just can’t do it hurts too much. I can’t do it.” You know, I’m just like, “Well, do it again, try again,” thinking that this guy, you know, doesn’t know how to push himself. Is he kind of wimping out here or what’s going on? And so after, like, the third time he did this, I got him to do like, 315 finally one day. I said, the fourth time, “So you know what you’re going to do on this one? I want you to do the 10 mile time trial, but I want you to do it in microburst for the entire thing. You’re gonna go at 150% of your FTP for 15 seconds, and then you’re gonna ride it 50% of your FTP for 15 seconds.” And he’s like, “What?” I’m like, “Yeah, you’re gonna piss off a lot of people when you sprint by them.” And then he goes, “But what happened?” He did that for that 10 mile, he cut two minutes off. Two minutes.


Trevor Connor  34:20

He is a sprinter, not a steady guy is.


Hunter Allen  34:24

So you got to keep that in mind, right? Because there’s two different types of people who have that ability to recover quickly. And so they may really benefit from the on off Tabata type nature or microburst intervals, whereas Mike’s a steady state rider, that may not be the solution for them.

Implementing VO2 Max Intervals and Threshold Work

Trevor Connor  34:43

Ex pro, Brent Bookwalter, has a lot of experience with VO2 max intervals and just how much they can hurt. As Hunter mentioned, he’s tried several different ways to accomplish the same goal. Let’s hear what he has to say.


Brent Bookwalter  34:56

The threshold work I was always quite still happy to do. VO2 work, I would usually get some anxiety and a little sick to my stomach before they even started. But also realized that it was critical for bringing me up and polishing that race form off. And yeah, I responded really well to it. Yeah, I mean, essentially, the VO2 work is like the keel over and collapse, can’t pedal anymore work. And the threshold work is the long deep burn and suffer prolonged for a longer period of time, but not quite as intense, more sustainable.


Trevor Connor  35:34

Fair, when would you use each? Or would you use them simultaneously?


Brent Bookwalter  35:37

It depended actually on different coaches I worked with through my career implemented that differently. Some of them would use them simultaneously, others would do specific phases with just one or the other. And my assessment after learning both ways is that there’s no magical way I think it can be done either way. There’s costs and benefits, I think, to doing them together. In general, I would say my personal experience in the training cycle, I think you can include both. There’s not a magic formula there. In the day and a specific session, I would say it’s rare to be able to do threshold work and VO2 work in the same session and have them both be productive. Just the mental toll on pushing and squeezing the body and the mind in both of those zones for one session is very high. And I think even for the strongest competitors in the world who are doing nothing but thinking about training, most guys aren’t doing that. Sort of like the classic VO2 session is like two sets of four by four. If you go to, there’s a climate in Drona in the middle of the summer, when it’s you know, primary season. If you go there, you’ll see a bunch of guys starting and stopping in the same places doing their four minute efforts out there.


Trevor Connor  36:44

Yep. And that is a brutal workout I did that many years ago. Wasn’t one to look forward to.


Brent Bookwalter  36:51

Yeah, I don’t know how quick I’ll go back to that one. Need a little detox time before I click back into another VO2 session. The other training, I guess on the  VO2 work is I think with some of my coaches, we tried to achieve that same VO2 benefit with intermittent work. So like primarily 40 20s or 30 30s. And I think in terms of the breathing, and the respiration, and the energy turnover that has to take place, I think it’s possible to achieve that VO2 benefit with a different power profile, with a more dynamic spectrum as well. That for me, it was always easier to do, I think because I was better at it. So I probably didn’t need to do it as much. But it was easier for me to do it that way and a little more fun.


Trevor Connor  37:35

Yeah I was gonna ask you about that because a lot of coaches are heading that way. They find that something like that 30 30s always and the 40 20s produce similar gains, but they’re just more manageable.


Brent Bookwalter  37:47

Yeah, it is more manageable for sure. I think what we have to remember there is there’s still a matter of of race specificity. You know, sometimes in the races, the power profile is very undulating, and the intermittent stuff is great for that. But other times, I had a point in my career when I was trying to make more selections over climbs and hanging out through crux points and climbs and doing the sustain load constant effort of three, four or five minutes does provide a different, it’s a different stimulus and feel on the muscles in the legs. And it’s different psychologically too to hit it and stay on that stun mode. As opposed to knowing like you’re only going to look at the clock for 30 seconds, and then you know you’re going to get a break.


Trevor Connor  38:33

No, that’s a good point. That is the hard part of those four by fours. You hit it hard you go, “Oh my god, this hurts, but I don’t have that much left,” and you look down and you’re only 30 seconds in. You got three and a half minutes to go. That’s the hard part mentally.


Brent Bookwalter  38:47

Yeah, but also empowering. I think one of the reasons I liked doing those sessions because they were empowering. You know, it was something that I prepared for and invested a lot in mentally before those sessions to make sure I was ready and push through really hard to get through them. And then there’s a level often that happens mentally to get into that race shape knowing you’ve managed that workout and survived it.


Trevor Connor  39:14

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Hunter Allen  40:46

I think absolutely, there is. Absolutely there is. I think that that’s something that you have to be very, very careful of. And back to the the table analogy, right? Again, FTP is the table top fingernails in the edge of the tables looking up at FTP. But you know what, you can go to the home improvements store and buy some hooks and screw some hooks down at the top of the table and lift up your FTP from those hooks. That’s how we can improve the FTP by doing VO2 max intervals. Okay, so you can improve your FTP absolutely, by doing VO2 max intervals. And it’s kind of the thing that you put, I call the icing on the cake, right? You do that towards the end of your build cycles. Especially if you’re building up to a peak of fitness, then that’s what you want to do is, let’s let’s do intervals at VO2 max to improve our FTP. Now, if you spend too much time doing those intervals, you put a lot of holes in the top of your table. And eventually that’s going to weaken the table and collapse it so to speak. So I think that’s something we have to be very careful of, is making sure that we don’t put too many holes in the top of our table and we make sure we keep that foundation of upper fitness, FTP and below, really strong. I’ll be very careful with those for steady state riders, for riders who are just pure aerobic machines, those riders seem to be the most sensitive to doing a lot of work above their FTP, that it could actually reduce their FTP if they get too much work there. For riders who have a bigger anaerobic ability, I won’t be quite as sensitive to that. I’ll give them more work at VO2 max because they can handle it. It seems to build their FTP even more, maybe they get an even bigger response. But both kind of riders need some work at VO2 max.


Trevor Connor  42:51

So why don’t we switch gears and now talk about threshold intervals? And Rob is the Sprinter in the room who probably hates doing these. This is my bread and butter, I would do them every day if I could. What are your thoughts on this?


Rob Pickels  43:05

You know, it’s funny because I actually don’t hate doing them. For me, and this is maybe a conversation for later in the podcast, when I’m thinking about intervals and what is appropriate, what is worthwhile, then it very much has to do with what somebody’s limitations are. And Trevor, as you know, and hopefully our audience has learned about me, the thing I love more than anything in the world is going on these nice, big, long, fun adventures. If I wanted to be the most successful cyclist I could be, I would be a sprinter on the track, without question. I mean, that’s where my ability is. Not even a road race sprinter because I have to get to the finish line with people. Forget that, I’m not even good at that. You know, but I could walk onto a track and be very effective. But I’ve chosen to never really race on the track because I personally don’t find that enjoyable. And it kind of goes the same way with these spring interval workouts. I could definitely play to my strength, but in all honesty, I don’t. You’ll find me oftentimes doing more VO2 or threshold related intervals. You know, because I think for me, that balances out my abilities. If I only ever did the one thing I was good at, I probably wouldn’t be able to improve the limitations that I have and become a stronger all around cyclists, which to me is important.

Execution of Training Intervals

Trevor Connor  44:19

No, that’s a really good point and I’m glad you brought that up. So Hunter, what are your thoughts? You mentioned that you’re not really getting the gains if you’re doing anything under 10 minutes. So it sounds like you’re a fan of longer threshold intervals. How do you typically have your athletes execute these?


Hunter Allen  44:36

Yeah and I think that that’s exactly what I’m thinking about threshold intervals. I want to, you know, I’m fairly, I guess classical or whatever you want to say. First I want to build a foundation of fitness with them. So I’ll start out with with sweet spot work to begin with. Make sure we’re getting plenty of where aerobically underneath your FTP, so that you pushed it to a, let’s say, three quarters of what you can be, what you can do, what your potential is. So I’ll do a lot of sweet spot work, I think it’s a great place to be, we get a lot of bang for our buck. Athletes don’t complain too much, they do it, it’s not too brutal. Once we get closer and closer to that last eight weeks, building into a peak of fitness, that’s when I’ll really introduce a lot of on the limit, on the edge, type FTP intervals. I am a huge fan of 10 minute one, I like 10 minutes because I think that you can ride at 105% of your FTP. It’s very intense, it doesn’t take that long, and you can rest, you know, for five minutes between each one, recover really well, not so much that you lose your rhythm, and then boom, you’re back in the next 10 minutes. I’ll do those, I’ll prescribe those more than anything, just because I think that one, the intensity makes a difference. And then the factor of you know, just mentally, I can complete 10 minutes much easier than I can ride for 15 or even 20 minutes. So I’ll do 20 minutes for sure, I’ll have athletes for 20 minutes. I’ll have them do 15 minute intervals as well. But those will be at 100% of their FTP or maybe even, you know, 98 or something like that, where the 10 minute ones will be at 105%. Or maybe just a touch above, especially at the VO2 max. So yeah, so that’s kind of where the range is.


Rob Pickels  46:43

Yeah, Hunter, I think that I’m in agreeance with you on the longer thresholds sort of intervals. And, you know, for me, I even tend to be more on that longer side, the 15 to the 20 minutes, maybe at 95% to 100% of your FTP. And the reason for that actually is not really scientific. I think that there are times when we’re prescribing intervals that we need to step outside the physiology and what it says on the research paper in front of us. And I think that oftentimes there’s a lot of really specificity based benefits to just being okay with suffering for 20 minutes when it’s uncomfortable. You know, we’ve all felt that feeling of, oh, the first five minutes feel great, you’re like, “I should go harder.” And then at 10 minutes, you’re going, “Oh, man, this is getting pretty tough.” And then you’re, you know, it’s kind of like that race of attrition almost at that point in time. And I find that to be really, really valuable for athletes, especially when they’re engaged in events, or courses, terrains that require these longer steady state, sort of outputs. You know, it teaches their stomach to feel okay, after a long effort, maybe even to take in some calories while doing this effort. And I think that all of those have really, really large benefits for actual race day performance.


Trevor Connor  47:56

So I’m kind of in a place in between the two of you, because Hunter I agree with you. I’m not quite 10 minutes, I often use eight minute intervals. But to me, that’s relatively close. I find them great for raising athletes power.


Rob Pickels  48:10

For clarification, you do eight minute intervals with very short rest intervals in between, correct? And that’s an important thing for people to think about. It’s not eight minutes all out, right?


Trevor Connor  48:19

Right. And so we brought that up, you know, five by five minute intervals with a five minute rest, that’s a VO2 max interval. Five by five minute intervals with one minute rest is really more of a threshold interval. And the eight minutes that I use, it’s a two minute recovery. But I do I’ll give a large block of that to my athletes, but then I give them about three weeks, where I want them doing a 16 to 20 minute interval at that intensity to for Rob’s point, which is you’ve built the power now we’ll learn how to hold this power.


Hunter Allen  48:51

Yeah, and then that’s always as a coach, you know, we’re always balancing the need to train a specific system for a reason. Okay, we need to improve this this area, we need to improve that area, etc, with the psychological nature of the actual intervals themselves. And I think that’s something that always is a challenge, right? And so, you know, I find in the winter, especially if I’ve got an athlete that gosh, they just need to maintain their fitness in the winter. You know, they do a lot of cadence work because it’s not boring. It’s kind of just like, “Well I’ll just ride these training workouts so that they’re not bored on the train.” And that sometimes, you know, we always have to think about too is what is mentally going to allow you to do these and meet the demands, I guess or the needed demands, in order to create the correct training stress.


Trevor Connor  49:49

And I think this is where I think we get skewered if we didn’t bring in Dr. Seiler’s research because he did so much research on four by fours, four by eights, four by six teams. Got it up in front of me. It’s great research, I could talk about it for the next 20 minutes, but I’ll just give a couple points here, which is really back in what you’re saying Hunter. In one study, he compared those four different intervals and pretty clearly the four by eights, and again, you said to use 10 minutes, but I think you’d see similar results. His four by eights seem to produce the best gains and aerobic markers. Four by sixteens had a lot of gains, but in another study, he showed that they kind of took the biggest hit to the free testosterone to cortisol ratio, which is a metric for overreach. So doing those four by sixteens, you’re starting to risk doing some longer term damage to yourself.


Rob Pickels  50:40

Yeah, I do want one point of clarification though, because in the Seiler study, those four by eight minute intervals were done at an average of 113% of VO2, which a somewhat corollary to FTP, you know, give or take a little bit, I’m not gonna say they’re the same thing. But I would put that actually in the longer side of the VO2 max quote on quote type of intervals, for what it’s worth. Now they did do also those four by four minute intervals, were at 130% of VT2, that’s more along the lines of what we were talking about before working at maybe your max aerobic power, as hard as you can possibly go for four minutes. And then the four by sixteen, that Trevor mentioned, those were at 100% of VT2, which is kind of a good corollary, again, for working right sort of at your threshold. So I almost I see this one study is one of the best examples of kind of a threshold versus VO2 sort of workout interval scheme


Trevor Connor  51:34

I’m interested in the thing that he concluded, which goes against that whole, more time at greater than 90% of VO2 max is better, is between all these intervals, and certainly the four by sixteens were much closer to FTP, he found they produce relatively similar gains in the different energy systems. And the argument that he made is it was really more about time. And it seemed that spending about 30 to 40 minutes at intensity was really the goal and not the intensity itself being the biggest factor. We did a video with Dean Gulledge, not long ago, and he brought this up and he went 95%, 100%, 102% of FTP, I don’t see a difference.


Rob Pickels  52:16

Yeah, I think that when we’re in a laboratory, and everything is really controlled, including people’s diets and the work that they’re doing to the second, then maybe you can start to see significant differences between, you know. But Hunter, as you’re pointing out, that’s not the real world. That’s not how any of us operate. You take that and you combine that with event specificity and even though Dr. Seiler, his paper clearly shows that four by eight minutes at 100 and whatever 15% or 120% increases all of these laboratory based measures, I as an athlete, and as a coach would not say that’s the only thing you should do, right? Nobody is saying, I mean, because otherwise, this paper is saying, “Hey, this is the only workout you should ever do every day of the week.” And we all know intrinsically, that’s not the case.


Hunter Allen  53:05

Right. And you know, and you got to come back to, as a coach, I know these work from experience, right. And so you’ve seen it work with other riders, you’ve seen it with 100 other riders, you know they work. There for you prescribed them. And so it’s like, well, this works, you know. And if your athlete you’re working with has confidence, 100% confidence in it, and does the four by tens exactly like you tell them to, two days a week, they’re gonna get better, you know? If they go out and they just kind of shirk it and don’t really do the whole thing, then you’re not going to get as good.


Trevor Connor  53:45

So before we get to our final question, I just want to say one last thing about threshold intervals, which is I do think the recovery length can be important, because remember, it takes time for your aerobic system to fully ramp up. That’s why if you do a threshold interval, you see that your heart rate takes a while to come up to threshold. And you don’t want to be relying on anaerobic metabolism. The point here is to train that aerobic system. So if you’re doing 15 plus minute threshold intervals, you’re gonna have a long time where that aerobic system’s really revving at 100%. And so there, I don’t think the recovery length is that important. I’ll tell my athletes take a longer recovery. If you’re doing something shorter, if you’re doing 10, or eight, or even five minute intervals, that’s where I think you need that shorter recovery so that you’re not fully repeating the anaerobic stores. And you’re also not letting the aerobic system come back down. You want to hit it again while the aerobic system is still revved up. And I always tell my athletes, if you’re doing like an eight minute interval, that first intervals almost a throwaway. It’s those next three where you’re really hitting that aerobic system.


Hunter Allen  54:50

Bingo. Bingo, 100% agreed.


Trevor Connor  54:53

Let’s hear from Dr. Robert Kenefick and his thoughts on the values of threshold interval work. Do you feel physiologically there’s a value to the VO2 max intervals? And is it different from the value you’d get from more of a threshold interval done right at that anaerobic threshold?


Dr. Robert Kenefick  55:11

I would say that I think both of them are valuable. I do think that higher intensity, like right at threshold work, would be valuable for a number of different reasons. Adaptation is probably one the biggest one, so we’re trying to adapt in those circumstances. And when you mentioned, those intervals are going to be rather short, because they’re so intense, you’re going to have a lot of lactic acid being built up. And there’s a lot of aspects of lactic acid that can begin to cause a decrement in performance, muscle contraction, etc. And so by being at those intervals, you have something like the lactic acid levels being very elevated into doing work, you know, a lot depends on how much rest is in between these intervals. But you raising that level, and now you’re having to work with that present. You begin to adapt to that, you become a fit, physiological adaptations and psychological adaptations. I think that’s valuable, in order to start to push up, what you mentioned at the first part is that anaerobic threshold, right? So you’re trying to get that to go up a little bit more. So doing that higher intensity work at threshold is going to be valuable to try to move that anaerobic threshold.


Trevor Connor  56:19

So let’s dive into the final question which you kind of touched on, which is now talking as your experience as a coach and what works, it sounds like you use both threshold and VO2 to max intervals. When do you use each? What point in the season? What’s the purpose for using each? What are your rights on?


Hunter Allen  56:36

Yeah, absolutely. You know, for me, I want to make sure that I’ve maximize the FTP gains that I can, before really moving to VO2 max. Unless they have a particularly difficult event that requires, you know, three to five minute kind of power. And so then I’ll give them VO2 max intervals. Before that, again, to really get them comfortable riding that intensity so they realize, oh, I can ride at this intensity, and still hang in the peloton and not blow. That’s more of a kind of a confidence issue, to be honest. Maybe you’d get a little benefit of doing those intervals, as well. But for me, I’m always thinking about when is my athlete peaking? Okay, they’re going to peak on August the 1st, then I need to make sure that I have their FTP as high as it can possibly be, you know, by July the 1st. Then we spend the month of July, teasing it up even higher possible, making sure that we’re getting in more intensity VO2 intervals. Not overdoing it, but giving them enough and having time for taper and rest lead into that peak on August the 1st. So I really apply them in two different ways. And that’s one, if we have a single peak of the year, I’m gonna win nationals or I want to do my best at this GranFondo versus okay, I’ve got a rider who is doing races throughout the year, and then they need to make sure their knife is pretty sharp, and then it’s really sharp on the weekends. So then we may put VO2 max intervals in a couple of intervals through the week. So you do a couple on Tuesday, maybe you do a couple on Wednesday and that’s it, in order to keep that system primed, so to speak. Is there a significant increase in VO2 max? Hard to say. You know, can I get their FTP up another 10 watts in that last month? Most likely, sometimes not, sometimes you can, etc. So, to me, I think it’s more of a, to that point, it’s a bit of an art in the prescription of them, especially in those last four to six weeks.


Trevor Connor  59:01

So I’m actually going to 100% agree with everything you’re saying. And I’m actually going to flip this around instead of doing what I normally do and try to talk about the specific energy systems you’re training. The way I always think of it is that threshold work makes you super strong, but it makes you a tank. So if you do all that threshold work and then you hop in a race and somebody attacks, you’re not going to respond to the attack. But if you did threshold work well, you’re the guy who’s going to be on the front of the field chasing it down, which means you don’t win, but you can do some work. The VO2 max intervals, whatever it is that they hit, whatever energy systems, they’re the intervals that are going to allow you when somebody attacks to respond and then maybe even counter attack them. It gives you that race burst.


Rob Pickels  59:46

And I’ve sort of long held the belief, and I don’t coach any World Tour, Pro Tour athletes, right? But I’ve long held the belief that the training that an individual athlete ought to do really should be related to the work that they’re doing out on the road, right? And if you are a team leader, then maybe the needs that you have are a little bit different than the domestique that’s doing work to help you. And maybe one of them needs to have a little bit more of an explosive, you know break away from people and the other, the domestique has to have a little bit more of that sit on the field and tow the team leader up the hill. And I would train them differently if I ever had the chance to train them.


Trevor Connor  1:00:28

Well up to that point, I am the constant, I was built to be a domestique from the ground up.


Rob Pickels  1:00:28

Lead me out Trevor.


Trevor Connor  1:00:35

I had great FTP, I think my VO2 max power was like five watts higher. I mean, it was comical when you saw my, if I did a 30 minute time trial and then a five minute effort, how close the wattages were.


Hunter Allen  1:00:49

Yeah and I think Andy Coggan said this. Coggan said this. Years and years ago we were somewhere and he was talking about it, it was a really good point. You know, he’s like your FTP is your ticket to play the game, right? It’s kind of like okay, is your FTP high enough to ride with the cat twos, then you can play the game, right? You’re in the game, you’re not gonna get dropped by the peloton, you can ride with the capsules. And so that’s your ticket to play the game. It’s your VO2 max anaerobic ability that is what gives you the ability to win. Because in every race, every race, even in every GranFondo, whatever you want to say, there’s always five minutes where it determines the race win, right? Always is. And sometimes there are races where you have multiple, five minutes. But if you grit your teeth, you recognize like, “Oh crap, this is the five minutes that I need to be on the limit here and above it, and I’m going to make the winning break or I’m gonna make winning split or I’m gonna win this race,” you recognize that, that’s really important. And that’s VO2 max, that’s FTP, that’s both of those things. But really, if you kind of look at some of the Tour de France winners over the past years, they’re very rare. Very rare when you have a just pure tank slash diesel rider who wins. Condell Evans was rare because he won the Tour de France and that guy had no anaerobic fast at all. You look at Alberto Contador, that guy, he could just freakin accelerate anytime he wanted to. So yeah, FTP, and anaerobic, VO2, and just boom, pop off the front, right? Because if your FTP is the same, right, let’s say you’re a World Tour pro rider and the tour this year. And your FTP is 440 and the other guy’s FTP is 440, but you have the ability to drill it for 30 seconds to two minutes or something like that. Now you’ve created that 30 second gap. And then now you’re back at 440 again. He’s back at 440, 30 seconds behind, right? And you’ve won the race. Yeah, so keep that in mind. FTP is what gives you the ticket to play the game. Your VO2 max anaerobic ability is what gives you the ability to win the game.


Trevor Connor  1:03:22

And the one thing I’ll say to all this is do the work. Do your threshold work, do your VO2 max work, time at right. But when you’re in the race and you hit that five minute moment, don’t look at your power. Don’t go this is above my VO2 max power, I have to back down. That moment, the thought that should be going through your head is “I do this or the race is over. So I give it everything I’ve got.”


Hunter Allen  1:03:44



Trevor Connor  1:03:45

Well Hunter, you’ve been on the show before so you know what comes next where we finish up. This is our one minute take homes where you get to summarize what you think is the most pertinent point or the thing you really want our listeners to take away from the show. So let’s let you go first.


Hunter Allen  1:04:02

All right. So I think the most important points are, number one, understand the relationship between time and intensity. If you want to train your FTP, then you need to make sure you’re doing intervals at least 10 minutes long. They need to be probably around 105%. If you’re doing 20 minute intervals, you know 100% is fine or 95% is fine, right? So keep that in mind. I’m training my FTP I need to keep this time intensity correct. Same thing for VO2 max. If I’m doing the VO2 max intervals and I want to improve my speed at VO2 max, I want to improve my power at VO2 max, then you need to do intervals between three to eight minutes. They need to probably be between around 106-120% unless you’re meeting like Rob. Otherwise you’re in that range. You’re training that system. So I think those are key take homes. You can’t do a four minute interval at 90% of your FTP and think you’re going to improve your VO2 max. Okay, well the four minute time is right. But 90% intensity, that’s like the FTP intensity, but four minutes isn’t long enough to create up training stress to improve your FTP. So four minutes and 90%, you’re wasting your time, right? So if you’re gonna do four minute intervals, make sure you’re there at 115% or so. So time and intensity, that’s the relation between those two and these two separate systems is important.


Trevor Connor  1:04:03

Right, Rob, you want to go next?


Rob Pickels  1:05:31

Yeah for me, the important variables here are the performances at these measures. So the VO2 max itself in terms of oxygen consumption, I think is less important than the workload that you’re doing at that point in time, because that’s what moves you down the road in the trail. Same thing with threshold. I don’t care what millimole of lactate that’s at or whatever, we’re talking about a functional situation where we’re talking about workload. You know, and I think that if we look just at research, those VO2 max intervals that we’re talking about might be superior in getting gains. But I know that research is more black and white than real life is. And because of that, I think that individuals do need to be doing both VO2 max style and threshold style workouts. Now, exactly what that workout is? Well that matters, who you are, and it matters what you’re trying to accomplish. And so either think critically about that for yourself to make the right choice or make sure your coach is thinking about that as you’re writing up a training plan.


Trevor Connor  1:06:29

So my take home has to go back to this question of what is the difference between VO2 max and threshold intervals? And you know, we had a good conversation about does VO2 max intervals truly train your VO2 max? Do thresholds really train your thresholds? I think there’s no debate about thresholds. VO2 max is probably still some debate. Personally, I think they train, there’s a lot of overlap, they train a lot of the same energy systems. So I’m gonna give a different idea of the difference between VO2 max intervals and threshold intervals, which is VO2 max intervals, if you’re doing them, right, you’re throwing up. Threshold intervals shouldn’t be that hard. They should be hard, but they’re pretty manageable. You can hold back a bit. So my biggest take home here are, is go back to what you said Hunter, which is threshold intervals are a great way of raising that table, getting yourself that ticket into the race, getting your level up. And then I think VO2 max intervals are something that you use for a shorter period of time in the season to give you that that race winning form. To me that is the biggest difference.


Rob Pickels  1:07:37

Well I think the final question should be, do you want to throw up for five minutes or kind of suffer for 20?


Trevor Connor  1:07:44

I know your answer.


Rob Pickels  1:07:45

I’ll take the short and sweet any day.


Trevor Connor  1:07:47

See my answer is why sort of suffer for 20 minutes when you can sort of suffer for an hour. It’s even better.


Hunter Allen  1:07:56

Well, I say you got to do both Rob. You’ve got to do both. Can’t just do one or the other, you know? You got to do both.


Trevor Connor  1:08:04

All right Hunter, it was a real pleasure having you on the show. Thanks for joining us again.


Hunter Allen  1:08:08

Glad to be here guys. Thanks for having me. A real honor.


Rob Pickels  1:08:12

That was another episode of Fast Talk. Subscribe to Fast Talk wherever you prefer to find your favorite podcast. Be sure to leave us a rating and a review. The thoughts and opinions expressed on Fast Talk are those of the individual. As always, we love your feedback. Join the conversation at to discuss each and every episode. Become a member of Fast Talk Laboratories at and become a part of our coaching and education community. For Hunter Allen, Dr. Stephen Seiler, Brent Bookwalter, Dr. Robert Kenefick and Trevor Connor. I’m Rob Pickels. Thanks for listening.