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The Duration and Intensity of Rest Periods Is As Critical As Your Intervals, with Sebastian Weber

Why do we have rest periods at all? In this episode we dig into the details of this question, along with examining different interval types and the appropriate rest for each.

Fast Talk Podcast Q&A

When Trevor first mentioned he wanted to do an entire episode about rest periods between intervals, I teased him—I often tease him—for being so excited about a seemingly mundane topic. Little did I know we would have such a compelling conversation with today’s main quest, the lead physiologist at INSCYD, and a previous guest on Fast Talk, Dr. Sebastian Weber.

So, why are rest periods so important, and why are we having this conversation? I think it’s safe to assume that when most cyclists design an interval workout, we focus most of our attention on the length and intensity of each rep. The recovery between reps? Well, that’s often an afterthought. Sometimes it’s flat-out ignored.

Which is a mistake, because the length of that recovery period has a dramatic effect on what energy systems are used from one interval to the next. For example, if two interval workouts are performed for the same length of time and at the same wattage, but one is done with 20 seconds of rest between reps and the other is done with 5 minutes between reps, they will be dramatically different, particularly in terms of how that wattage is produced for subsequent reps. We’ll emphasize that fact again and again in this episode.

We’ll start today’s show with a simple question, one that few athletes ask themselves: why do we have rest periods at all? Then Trevor and I will discuss the metabolic milieu that is “perturbed” during intervals, and what happens next when we rest.

For most of the episode, we’ll talk about the different interval types and the appropriate rest for each—everything from threshold intervals to VO2max intervals, from 2- and 3-minute intervals to Tabatas and sprints.

Again, our main guest is Dr. Sebastian Weber of INSCYD, and we’ll also hear from national champion Ruth Winder, Dr. Stephen Cheung, and exercise physiologist Jared Berg. Who knew rest was so important? Well, Trevor did, and after this episode, you will too. Let’s make you fast!

Let’s make you fast!

Episode Transcript

Chris Case  00:12

Hello, and welcome to fast off your source for the science cycling performance. I’m your host Chris case. When Trevor first mentioned he wanted to do an entire episode about rest periods between intervals. I teased him. I often teased them, I always tease him. He was so excited about a seemingly mundane topic. Little did I know, we would have such a compelling conversation with today’s main guest, the lead physiologist at inside their previous guest on Fast Talk, Dr. Sebastian Weber. So why is rest so important? And why are we having this conversation? I think it’s safe to assume that when most cyclists design an interval workout, we focus most of our attention on the length and the intensity of each interval Rep. The recovery between reps however, well, that’s often an afterthought, sometimes flat out ignored, which is a mistake, because the length of that recovery period has a dramatic effect on what energy systems are used from one interval to the next. Take, for example, to interval workouts performed for the same length of time and at the same wattage, but one is done with 20 seconds of rest between reps and the other is done with five minutes between reps. They will be dramatically different particularly in terms of how the wattage is produced for subsequent reps will emphasize that fact again and again. In this episode, we’ll start today’s show with a simple question when that few athletes ask themselves, why do we have rest periods at all? Then Trevor and I will discuss the metabolic value that is perturbed during intervals, and what happens next when we rest. For most of the episode we’ll talk about the different interval types and the appropriate rest for each everything from threshold intervals to vo to max intervals from two and three minute intervals to devadas. In Sprint’s again, our main guest is Sebastian Weber of inside and we’ll also hear from National Road champion Ruth winder and physiologists, Dr. Steven Chung and Jared Berg. Sebastian has created a webinar that will complement this episode as well. So please visit the Show Notes for this episode. For a link to that presentation. Find it at Fast Talk slash Fast Talk. Three new rescue so important. Well, Trevor did and after this episode, you will too. Let’s make it fast. Well, it’s it’s great to have you back on the program Sebastian Webber, it’s been since Episode 73. I believe it was we also had you on for Episode 67, where we talked about some of the metrics you have worked to create at inside Vla, Max and other things. So welcome back to the show, Sebastian.


Sebastian Weber  03:01

Yeah, thanks for having me again.


Trevor Connor  03:03

And so we were just talking offline. And we were asking you how you were getting through these times? And you said, Oh, no, I’ve been busy. So you said there’s been some big changes that inside? Did you want to tell us a little bit about what you’re about to launch?


Sebastian Weber  03:16

Lie? Yeah, I mean, we did, we did actually work on on a new technology for almost two years. I’m personally pretty excited about it. Because I think it’s the first tool ever out there in terms of performance assessment, which is actually allowing you to combine data of different sources or left left data, we have your view to analyze our lactate data, or just power duration data, which you know, most of your listeners will be familiar with, I guess. So it’s called the power performance decoder, because obviously, if you needed to find a fancy marketing name here, it can work completely on remote data. And and it works as I said, in combination with lactate data just as you just as you like right and he’s been through some extensive testing with some virtual cycling teams on some cultures and obviously did our homework in terms of validation and we just launched approximately three weeks ago ish. And therefore as has been very busy, obviously to get this out to roll this out. And then afterwards obviously to get all our users and all our coaches and especially all the professional teams and organizations Federation’s getting up to speed on how to use it.


Chris Case  04:29

And and just to point out to people, if they’re hearing cowbells in the background, if they’re hearing birds chirping in the background, it’s because you’re at home in Switzerland near Yes, you’re some farmers and just enjoying the day or the evening for you.


Sebastian Weber  04:46

Exactly. Yeah, that’s what it is. hope that’s not too annoying.


Chris Case  04:49

Sorry. No problem. Well, yeah, let’s today we want to talk about something I don’t think too many people do address a lot of athletes have come to us asking the question, How long should I rest? How much should I rest between intervals? What difference does it make? If between my threshold intervals I rest 30 seconds or five minutes? Should I always do the same type of rest between intervals? So we really want to answer some of those questions. And maybe First, we should address the question of why there’s so little research out there about this very question.


Sebastian Weber  05:27

You asking me why there’s not so much research out there? I don’t know. There’s some, there’s some fundamental research, basically, on muscle energetics, and, you know, pH levels, and so on and so forth. And I think what often happens, that we maybe look too much on the, you know, when we search for things, we maybe search too much on the on the Applied Science side of stuff, right, where you look for, oh, you know, can I find a training study where they used different training interventions? That’s great. And I think, you know, I also don’t have, from the top of my mind many studies that I can remember, but you look at the adaptation in terms of, you know, the training stimulus or the benefit you get from altering your arrest into laws. But in terms of the mechanics, what happens during the resting, I think that’s, you know, that’s some basic physiological knowledge, which is, which is indeed out there.


Trevor Connor  06:29

This is something that Chris and I were talking about before, what is physiologically, the purpose of the having the rest? So, you to really simplify this and oversimplify this, let’s take a standard interval, like five by five minutes. Let’s say you do those intervals at 270 watts, why not? Just do 25 minutes? 270 watts? Why have intervals? Why have the rest?


Sebastian Weber  06:57

Well, that’s an excellent question. And for me, is a blind spot really here and scientific research is, is and there’s not a lot, there’s a little bit but not a lot is to is to, you know, compare intervals where the steady state exercise, so to speak, or steady exercise constant constant load for matching workload, because most studies do because, you know, we compare whatever long slow distance training, so constant workload president of UCLA but then is not matched in terms of intensity and time. So one question that that I personally find very interesting here, if I’m at this is, is looking at is the training stimulus different just because the alternate intensity, so it would be even matching workload and matching intensity? That’s, that’s one thing. And then the other question, what is the purpose of the what is the purpose of the rest? What is the purpose of the off phase? I think that pretty much depends on the kind of interval training that you’re doing, are we talking about sprint intervals or longer intervals or whatsoever? Original, obviously, it comes from the idea, let’s say whatever, let’s say you say, I want to, I want to spend, I want to spend whatever, 10 minutes or 20 minutes total at power x, let’s say 300 watts over server. But I’m not able to do it continuously. Then the rich idea I think comes from I just break it up, right, I just break it into different snippets or different pieces. And therefore I’m, I’m able to complete the total work the total time, let’s say 20 minutes, I just need to break it up into five reps, for example. Right? So that’s obviously the benefit that I can, I can get higher and longer work done, so to speak, by breaking things up.


Trevor Connor  08:51

While back, Chris, and I had a chance to talk with Ruth winder, the current American National Road champion. And we asked her this question about rest periods and intervals. And why do them? Interestingly, well, she certainly recognize there’s a physiological value to them. For her it was almost more about motivation. When you’re doing intervals, how much do you focus on the rest period, both between your reps and between your sets? Do you feel that’s really important? Or is it just, yeah, just pedal easy until I feel like I’m ready to do my next next Rep.



I like to follow my workouts strictly as I can. I feel like I get the most feeling of success when if it says, you know, 10 minute interval with eight minutes rest, then I will be like as close to the eight minute mark as humanly possible. Sometimes I’m given like, between an eight and 10 minute recovery or something like that. So then sometimes be like nine minutes right in the middle. So you know, go go for something like that. But yeah,


Trevor Connor  09:45

I don’t know. Is that a mindset thing? Or do you think physiologically that’s helping you and I will tell you, I’m somebody I remember one time doing sprint sets and had 10 minute recoveries. And I got to the start line where I was gonna do my sprints and sat there in circles because I was at like, 915, and then realized I was Nydia,



yeah, um, I think that is also we’ve that has loosened off a little bit. as I’ve gotten older, I think to us, I’ve learned that I’m like, my race is not gonna be won or lost whether I do nine minutes and 55 seconds of recovery, or 10 minutes and 20 seconds of recovery. So I definitely have like, become a little relaxed about it not like to so much to the point that I’m adding myself minutes, but I don’t believe that it’s making or breaking my fitness.


Trevor Connor  10:24

So what’s a good guideline to say this recovery has been long enough?



I guess it depends on what you’re trying to achieve from the workout. Like if the workout is intended to have limited recovery, so that you feel really shy for each interval, then just suck it up and do the two minutes of recovery like your coach told you to do. But then if he that your coach has been like, this should be a full recovery. And that’s when you really should pay attention to your body and be like, Okay, this 10 minutes, I don’t feel fully recovered. So let me try 12


Chris Case  10:50

there’s not much science behind the effectiveness of different lengths is there that’s kind of what we want to explore in an episode is how critical is that rest period? Like you touched upon? Sometimes you want it and sometimes you don’t? But if it’s so long that you’re fully recovered? Is it does it really matter or,



or what it does vary by the type of interval, I think that there are a lot of times that people just really like to follow a program. And like the competence and following a program, whether it’s right or wrong is like what a lot of people especially during the week, and they only have an hour to ride and they want to get they want to feel successful, like having a specific amount is really confidence inspiring. And I definitely feel that at times, sometimes it’s like, I don’t really care if this is right or wrong, but I want to be I want to do what I’m told, and I want to feel successful at the end of it. And most people it’s as long as they feel tied by the end of it. So if you give people a two minute interval, and then give them 15 minutes of recovery, they’re not always gonna like come back feeling like they did a really hard workout or something like that. So sometimes it’s just what you’re trying to achieve from the day. And if you only have an hour, then maybe a little less recovery is better for something like that. But it would be really interesting to learn about,


Trevor Connor  11:57

we talked to in a previous show where you talked about devata cell intervals. And obviously that 4020 years is critical. The 20 is just as important an element in that workout. But if you’re doing something like a threshold workout along threshold workout, are you very particular about the recovery length?



Yeah, but I think I think it’s just whatever my coach said, I don’t know, necessarily that I know that it’s the right or wrong thing. I just think that I like to follow my program. No, that’s like, follow my program, but I have become like a little bit more relaxed. I’m like, okay, it doesn’t have to be exactly 10 minutes on the absolute top. But I’m also not the kind of rider that will like circle my parking lot until I’ve like the exact hour number that I was supposed to do for my ride. So I think it depends a little bit on who you are. And if you get a lot of confidence from doing like, exactly what you’re told, then being a good cyclist is like got a lot to do with confidence. So you do I need to do to feel confident me, I can come home at two hours and 55 minutes, which was supposed to be a three hour ride and feel totally confident that I did what I needed to do for the day. So it’s just kind of depends bit on that.


Trevor Connor  13:00

Let’s take a bit of a deep dive into the physiology. So he agreed, particularly if you’re doing really hard, more anaerobically focused intervals, you need those Rossville to produce the intensity, what is physiologically going on, when you’re taking that rest what’s changing, that’s allowing you as you said to produce the intensity every time.


Sebastian Weber  13:26

Well, very simplified, saying you kind of reverse or you’re trying to reverse your fatigue, right. And on a macro level, so to speak, because that’s what you’re doing throughout the whole week or months of training, right? When you let’s say train 10 hours per week, you’ll most likely also come Don’t come to the conclusion I can train 10 hours on one day and then rest for another six days and 14 hours. Right. So a week is also similar, right? So similar idea. I want to have a resting phase in order to be you know, ensure a good quality for the next repetition. Next training day, so to speak. Right to answer your question, I would say let’s imply here that the interview that you did was kind of exhaustive, right maybe was not too full exhaust and you maybe didn’t puke on the handlebar. But very, very close to that, let’s say then, then basically why you’re doing this rest is you want to restore, you want to reset your system more similar or more likely, more similar to the state of rested system, physiological system talking energetic system talking in order to allow for another repetition at for example, the same quality or same duration and same intensity. And what exactly in terms of energetically physiologically you’re looking for to recover that can be vastly different again, depending on you know, are we talking about a sprint interval training are we talking about longer intervals, you know, These candles and obviously I’m I’m here on talking about the physiological side offset, right? I’m not talking about the psychological side, I have no clue about that. Really, I guess, when it comes to you know, are you more prepared? Are you ready again? Are you motivated to the next center? Alright, so let’s maybe keep it on a physiological view for for now.


Chris Case  15:20

Before we spoke with Sebastian Trevor and I discussed the topic of metabolic perturbance, as well as two studies that looked at the importance of rest periods during interval sessions. Let’s listen to that now. What does a rest period accomplish physiologically speaking, what are we gaining by having them


Trevor Connor  15:40

there’s two things two things that you want to look at without rest period one is influence on fuel. The other one is an influence on the metabolic meal you


Chris Case  15:53

mirror my love. Mmm, yes, it just called the M M.


Trevor Connor  15:57

And we’ll go into in a minute, the mill you and talk about metabolic perturbance. And all sorts of fun terms is gonna be exciting. Let’s talk first about fuel. The idea here being you are going to deplete some of your fuel. So you need some rest time to replace it.


Chris Case  16:16

And badly did Yes. replete is that word is it is


Trevor Connor  16:21

is in science world.


Chris Case  16:22

Okay, good. I like it. Otherwise, I got it. I don’t like pleats on my pants. But replace a cool word.


Trevor Connor  16:30

That was not funny.


Chris Case  16:32

Jenna’s laughing a little bit,


Trevor Connor  16:35

she’s laughing at you, that’s fine.


Chris Case  16:37

Or beside you any any type of laughter in my mind is pretty good. There you go laughing me all the time.


Trevor Connor  16:43

So remember, we have three types of fuel, primary types of fuel, you have fat, which is essentially unlimited. So that’s not something you need to replace. Chris is just like in this replete



word I love repeats fat


Trevor Connor  16:58

is constantly available, you have glycogen, you’re not in a four minute interval gonna deplete your glycogen. But if you do a long interval session or a long time trail, you do run the risk of depleting your glycogen. The other primary fuel, which is your one year, basically your your main short, anaerobic fuel is phosphocreatine. Mm hmm. And you deplete that very quickly. So if you are trying to do, let’s quickly talk about what all this means, if you’re trying to do short, really high intensity above the max intervals, you are going to deplete that. So phospho create in a short form is PCR, you’re going to deplete PCR pretty quickly. And you need some time to recharge that in order to be able to do the next interval with high intensity. Mm hmm. As I said, with glycogen, you’re not going to deplete it in a four minute interval, but over the course intervals, you are going to start depleting it. So that’s going to influence how much interval work you can do.


Chris Case  18:02

And we’re going to get to this. But because of these issues that are coming up in terms of depleting fuel sources, you need to vary the length of time that you rest to be able to replete them.


Trevor Connor  18:15

Yes. So that this is kind of the point I’m getting to which is you need time to replete phosphocreatine it has a two stage recharge, I’m not going to go into the details of but basically it is mostly repleted in about one to two minutes. So bulk of it in about one minute. So if you’re doing that high intensity work, and you want to make sure you have full peace PCR storage, you need at least a minute you’re probably better with to flipping it around. Like I said, fat is unlimited. But there is where you burn fat is in the Krebs cycle. Krebs cycle is a little slow to get going. So if you hop on your bike and start working, you’re actually going to mostly generate energy with glycolysis. Well, this big thing of this big monster Krebs cycle starts ramping all the way Yeah, and it needs the by the end products of glycolysis in order to function. So as strange as it sounds, were to replete phospho creatine, you need a long recovery. If you’re trying to really focus on using fat for fuel, not using a lot of anaerobic metabolism. You want to make sure your recoveries aren’t too long. Because if you get off the bike and rest for a long time, and then you go and do another interval, it’s going to take time again to get that cycle up and running to get that to where you’re fully doing aerobic metabolism. So when I actually get my athletes, longer intervals, more threshold focused intervals, I’m actually going to somewhat limit the recovery length. I don’t want them taking 10 minutes in between those interests,


Chris Case  20:01

right? Yep.


Trevor Connor  20:02

So now there is also this whole metabolic meal, you and there, there’s three parts to it. So it’s basically the idea of inside the cell, you have a homeostasis that you want to maintain. And that’s, in particular, there are certain metabolites, that your body wants to keep them balanced, they get out of balance when you’re doing intensity. So we actually just talked about one, which is phospho, creating, so you’re gonna, if you’re doing really high intensity, you’re gonna deplete that pretty quickly. The other one, when we start talking about acid base balance, you’re talking about what we’ll look at lactate. But really what we’re talking about is hydrogen ions, they’ll get out of balance really, fairly quickly when you’re doing interval work. And actually, in that same study by Dr. Seiler, he talked about generally, when you’re doing interval work, you’re you’re looking for this optimal, you want to see blood lactate to be kind of five to 10 millimoles. So the last one, and this is getting a little deep into the weeds is restitution of transmembrane, potassium. So very, very short. If you remember your high school physiology, we have these transporters on all of our cells that transport potassium, into the cell, get sodium out of the cell, because you want to keep potassium in your cells, you want to keep sodium out in the extracellular fluid, when you are doing high intensity, that’s going to get out of whack, you’re gonna start seeing sodium come into the cell, you’re gonna start seeing potassium get out, that’s going to affect your ability to function. So you need to restore that balance as well. This mill you, these different things take different lengths of time to recharge. So we talked about phosphocreatine, it’s a two phase thing, it takes, like I said, about one minute to get most of it two minutes, if you really want to be fully recharged, transmembrane potassium balance. Again, it’s pretty well recharged within about 60 seconds. And these are the things that really get out of balance, when you’re doing super high intensity, right? The restoring pH takes five to 15 minutes for the half life. So much longer recovery. But that’s not necessarily a bad thing. Because the belief is you want high lactates when you’re especially when you’re doing that aerobic type work to really see the benefits,


Chris Case  22:46

right? So and to remind people lactate isn’t is a fuel source that’s being used here. It’s not where you shouldn’t be thinking about it as this evil thing all the time.


Trevor Connor  22:58

Yeah, if you want to hear my full rant on the fact that lactic acid doesn’t exist in our body, and you got to stop using that term, we did an episode on that I can’t remember the number that goes way back in the 30s. I think that but lactate is a fuel as a matter of fact. So the reason we thought it was lactic acid is because lactate gets pumped out of the cell with hydrogen ions. And basically whenever you’re talking about acid, you’re talking about a buildup of hydrogen ions. So what researchers were seeing a long time ago was Oh, look, lactate levels are going up, and pH is going down. So we must have lactic acid. But actually what it is, is your body is using lactate to transport the hydrogen ions out of the cell to actually maintain homeostasis within the cell. So lactate is actually helping to buffer effectively the acid. lactate is a fuel and a lactate is actually a base, which is the opposite of an acid, right? By the way, every acid has both its base form and its acid form. So lactic acid is the one form. lactate is the other.


Chris Case  24:04

Yeah, and that was Episode 30. For anybody who wants to hear me good rant, rant, rant, not rant, just educate. That’s all you’re doing. Oh, no, it was rant.


Trevor Connor  24:13

Okay, I will rant on it. The whole point here is you are getting out of homeostasis with fuels potentially with this metabolic meal you so when it gets out of balance, we are causing a metabolic perturbance who these terms. So we need to restore all this the so there’s two theories here. One is that you need to restore, get back to some sort of homeostasis, you need to restore this so that you can do your next interval with high quality, right. That’s the one theory so that theory tends to push towards. You need more wrestling. Mm hmm. Make sure that is fully recharged, right? Another theory, which has been around for a long time, and is probably the the one that at least in the research I was reading I saw more is no remember, fundamental principle of training is you need to cause a stress, big enough a stress that it promotes training adaptation. So my belief was you want to actually promote these perturbations is, the bigger the perturbance. The bigger the stress, the higher the training, adaptation. So, if you look at it that way you say, you want, short enough, long enough an interval that you can continue to do the work. But otherwise make it as short a rest period as possible, so that you’re not fully restoring homeostasis, right. So the belief there would be, you’re doing really high intensity, yeah, you probably want to restore phosphocreatine. So you can do the intensity. So maybe 30 seconds, or sorry, 62nd. Rest, but not much more, because we want to maintain all the other perturbance as much as possible. Mm hmm.


Chris Case  26:10

It does sound like, given the lack of research that’s looked into these questions. We don’t have extremely clear answers on this stuff. But I’m guessing there’s a lot of nuance here. Sometimes you want to go in one direction in terms of being fully recovered. Other times you want to you want to give your body limited rest. So you, you maintain a perturbance so that you then increase adaptation, or That’s the goal. What I found interesting is the few studies I did find on red flags.


Trevor Connor  26:47

There are one or two that said, Yeah, there was some benefits it was normally if the rest is too short, you lose quality. And it’s not as good an interval session. Beyond that Muslim are saying Yeah, for not finding a big difference. And one of the ones that I found the most fascinating that really talked about this metabolite perturbance. They actually set up a study with different two different Wrestling’s. So they were having athletes do two minute intervals. And then one group was doing one minute rest flanks. Another group was doing three minute Wrestling’s and I have to call out this study, I really admire them, they used all female subjects, which is rare. We talked about that in a previous episode that most researchers go with males, because frankly, males physiologically are simpler. But that’s not a good reason. Yeah, yeah. And we do need to study women. So I fully admire them for saying, Let’s do a study with women looking at the effects of this. So So kudos to these researchers. So this is a study from 2013 in experimental physiology, and they looked at lactate, they looked at hydrogen ions, they looked at ATP levels, they looked at fossil creatine levels. A few others that we didn’t bring up and I’m not gonna bother bringing up but it was it was good study, they found that the group that did one minute recoveries, had a much larger perturbance. And all these metabolites, so you saw higher lactate levels, you saw higher or lower pH. So basically bigger acid build up is greater depletion of phospho, creating like everything, they were really hitting the system versus the group that was doing three minute recovery legs. They had these two groups do these intervals for five weeks. At the end of the five weeks, both groups. So big improvements in threshold power, and vo two max power. And basically they all got a lot fitter. Sure, and there was zero difference in their adaptations. Even more interesting. So going back to those two theories, one of the things that we look for is bodies, you want your body to improve its ability to naturally return these things to homeostasis, right. So if you want to perform in a race, you don’t want a big acid buildup, you don’t want to have depleted phosphocreatine. You might want to cause that in interval work to produce an adaptation but you want in a race if you do a sprint in the middle of a race. Yep, you want to recover quick. Yep. So you want to see your bodybuilder return to homeostasis much quicker. So their actual hypothesis was the group with the shorter recovery would see greater improvements and be able to return to homeostasis. Also completely not to see it.


Chris Case  29:50

And you said five weeks, the interval sessions were always the same. The only thing that changed was the recovery group was one minute and the other group was three minutes. Do you think that those two rest periods were too close together? Like they should have done a 32nd group and a five minute group or something like that? Spread it out a little bit more?


Trevor Connor  30:11

I think it’s Yeah. What you need is a lot of research. Sure, trying all these different things. And that’s one of the issues. Is there. So little research, it would be great to have one that does 30 seconds, 15 seconds, I did find a few. That said they were studying recovery lengths where they did those shorter. What about a 15? Second recovery? What about 32nd? What about a one minute recovery? One did find some differences. But my issue with that one study was they also altered the interval length. They were doing one to one on all of them. So they did a 1515, a 3030. And a one minute, one minute, right? And then said, Oh, look, there’s differences. So the recovery length makes a difference. You go but you modify to variable. Yeah,


Chris Case  30:53

yeah, that doesn’t make too much sense there.


Trevor Connor  30:55

So this was one of the few that I found where they said, No, the actual intensity portion is going to be the same. The recovery length is going to be different. The other study was actually that Dr. Seiler study where they had them do six, four minute intervals. And then they had groups do either a one minute recovery, a two minute recovery, or a four minute recovery. And what they found was between the groups doing the one in the two minute recovery, the groups doing the two minute recovery, were able to do the intervals at a slightly higher intensity. Now they this was not a do these intervals for five weeks study. So they weren’t able to look at long term adaptations. This was just looking at the effects on their ability to perform the work. They found actually no difference in the group doing four minutes. More interestingly, they had a fourth session, where they allowed subjects without beyond to see a clock to self select recovery length. And the worked out 218 seconds. Well, so almost exactly two minutes. Interesting. So the gist of their study was, and they again, brought up all these different the this this metabolic perturbance pointing out that Yeah, you know, the PCR and the potassium imbalance, both restore within about a minute to two minutes, lactate and acid balance take much longer. So really, you’re probably going to be ready to go after about two minutes. Chris and I talked to Jared Berg recently the former lead physiologist at the University of Colorado sports medicine Performance Center. Before we take a deep dive of Sebastian on the appropriate Wrestling’s for various interval types, let’s hear a quick summary from Jared, does the rest between reps really matter? Or is it just making sure you recovered before you start the accident? Like does a minute versus two minutes versus 30 seconds? really matter?


Chris Case  33:03

It does



matter? And I want to understand more about that. All right, and Molly, Molly Brewer, my colleague in exercise physiology here, you know, we do a lot of the same testing and work with athletes. We thought about trying to just you know, get some people in having them, do, you know, an interval, just, you know, above threshold, and then coming back and doing some time at the very top of aerobic threshold, right and see what like, what lactate does he was happening metabolically, see if we can train someone to shorten that rest interval need. And then also maybe looking at, you know, big over unders or a popular set, it’d be really fun to just sort of play around looking at what what does an overunder look like physiologically to somebody actually get under after the rover? Right. You know, it’s just things that, you know, maybe have been done in some labs, but I just haven’t seen the research on it kind of fun to play around with that.


Trevor Connor  34:00

What would be some guides, you would give on wrestling between reps.



So if you’re going above threshold, I feel like and you’re approaching sort of via to max interval, thank rescued could be equal. I mean, just in general guideline residue, and a five minute five minute rest, exactly two minutes, two minute rest, right? If you’re going above the two Max, right, because we can go above the 80 max with efforts, then we’re looking at double time rest, one and a half to double time rest. So you go, you know, for 30 seconds all out sprint, then you’re probably gonna want to rest couple minutes. Right? That’s even more than double time. All right, you know, and so if we look at the metabolic systems, right in about, you know, some of us can recover from a 32nd effort in about four to six minutes, you want to really get a maximum 32nd effort. You probably need about four to six minutes of recovery depending on a person if Same thing for a max 10 second sprint, right but we can recover from sort of a via to max sort of effort. Yeah. In about equal time, we’ve offered a threshold effort. I feel like now you’re getting towards, you know, three quarters to half time the interval length for rest. Okay. Yeah. And then anything sub threshold like sweet spot, it’s more rest just to keep your mental clarity and focus.


Chris Case  35:19

All right, well, let’s get into a deeper discussion of the different types of intervals and the importance of rest between those intervals. Let’s start with long intervals, say, greater than four minutes in length. So what systems there are we targeting? What do we want to talk about here? What bring in some of the metabolic perturbations that we spoke about earlier? What’s going on in those longer intervals that you need to address with your rest periods? Sebastian,


Sebastian Weber  35:54

depends on what kind of intensity we are talking about. So when we describe an interval, we should be really precise, not only in the duration, because obviously, I can do four minutes, for example, at threshold or slightly above, or I can do four minutes or whatever, five or six, eight or whatever, till exhaustion. And that changes a whole lot, actually. Right. So the question is, is that just threshold and device or slightly above threshold, and therefore the break is maybe a little bit like the respirator is maybe a little bit more for convenience, right, because I obviously could continue longer, or is that is that an interval where we go close to exhaustion, and we really have a high level of fatigue here, this is very important when you talk about the resting period, or how you should design the resting period, actually,


Trevor Connor  36:41

which I agree with completely. And I’m glad you brought that up. Because if you hadn’t, we would have asked you about it. Let’s talk about both, and let’s separate them. So the let’s first talk about that interval that’s done at threshold where like you said, even if you’re doing eight minutes, 10 minutes you use, and you stop at the end of that time period, you probably could have kept going at that intensity. So you’re taking a rest, and then we’ll talk about that more four or five minute interval where you’re doing them as hard as you can do. So let’s start with that more threshold type interval.


Sebastian Weber  37:15

Yeah, so then, you know, if it’s more threshold, like threshold or slightly above, and you end after, like after duration, which is not exhaustive for you, and you could easily kept going longer than the interval, it’s like this is it, the resting period itself is not as important. Neither length or intensity, as long obviously, it’s, it’s a lower intensity. That’s why it’s because as you know, as long as that is a given, it’s not changing a whole lot in those kind of intervals. And that’s basically because if you look at all the fatigue markers, so to speak, or the physiological metrics that can change during an interval at threshold or slightly above. So for example, accumulation of lactate, decreasing pH levels, decreasing creatine phosphate concentrations, there’s not a lot happening. So all these metrics, they don’t change a whole lot, they start to change a whole lot when you exercise above threshold. So when you add threshold or just slightly above, then, you know, the resting period, again, is a little bit more maybe for convenience, maybe because you want to see a big alternation and heart rate levels, which, you know, is a fair thing to do. So that’s a liberal education. And then it’s it’s Yeah, it’s it’s not really that that important, how you do that.


Trevor Connor  38:37

So I’m actually we mentioned earlier that 2005 study by Dr. Seiler talking about Wrestling’s and one of the things he brought up in that study is this type of work, you really want to keep your lactates high that you his, his feeling was you get greater adaptations, if you’re doing these intervals and your lactates are up in the four or five millimolar range is I think what he had in the study, but also, as we talked about earlier, the it takes a long time for your lactate levels to return to normal five to 15 minutes. So you don’t want to have such an insane length rest period, that your lactates come down. Mm hmm. But you can take a few minutes. Sure. And lactase are going to stay high, and you’re still going to get those gains. And the next interval. Would you agree with that Sebastian


Sebastian Weber  39:26

was the missing part here is that is the intensity of the ANOVA. If you do these intervals, and let’s say you rest for eight minutes, and you just lay down flat on the road and don’t move. The amount of lactate you can combust is comparable. And everybody knows it by feeling because when you get up into the next enter, your legs will feel pretty heavy obviously. Right? Yeah. So that’s, that’s obviously that’s obviously a question. And then, I mean, if it’s about if your idea is to get to high lactate concentrations, and If you don’t mind doing that, what you could simply do, you could just go the first 30 seconds or one minute of that interval much, much harder. Obviously, the harder you go, the shorter you could do this little bit of extra work. So you could overpay, so to speak in the first 30 seconds or something, shoot yourself up to high lactate concentrations. And because you’re exercising at threshold or slightly above, you will keep this lactate concentration or increase it slightly. So that could be a modulation of this, if you know if this is a desire to go to stay at dielectric concentrations, and, and you don’t mind doing this, that extra work in the beginning, so to speak. That’s one way you could do it.


Trevor Connor  40:36

That’s interesting, because that’s my old coach, when he gave me these types of threshold intervals as exact Oh, they had me do was first 30 seconds go harder, then he liked five or eight minute threshold intervals at threshold. So you’d have to do 30 seconds really hard. And then do the rest of it right at your threshold power, right.


Sebastian Weber  40:57

I mean, what is what is most certain is that you need high lactate concentrations, to also stimulate a higher lactate combustion rate, so to speak, or simplified speaking, very, very simplified speaking, if your lactate concentration is relatively low, then not a lot of lactate is pushed into the Krebs cycle and does aerobic metabolism. But when it’s higher, you can push more into that certainly known. So then on top of that, there are some indicators that maybe your lactate transporters, your lactate shuttles, because they’re similar to blood, like glute for transport or look similar as, as well seems like could be, could be activated by lactate concentration. So if you if you would assume that this is a training adaptation you want, so to speak, training or simplified speaking, teaching your muster to shutter more lactate or use more lactate, I will totally agree is that and this is what you’ve you’ve been using in professional cycling, also, in the last 1015 years or so, you know, trying to do these intervals over and unders and stuff at threshold, so to speak, or slightly above, doing it primed so priming yourself as I like to concentration, because he assumes that, you know, you can trigger your system to shut it and combust lactate, there’s an additional trigger,


Trevor Connor  42:18

that’s actually something has been really important to me with my athletes when I’m having them do this type of work actually don’t want the length of the recovery to be too long. Because as I think I’m hearing from you point out that the the Krebs cycle is slow to get running. And you want to get it running, and you want to make sure that it’s still running optimally, when you’re doing these threshold intervals so that you are effectively burning fat, you’re actually working those aerobic systems. But as


Sebastian Weber  42:49

it cannot take off the Krebs cycle is not really limiting here, because we have to remember we come from like, when we enter the resting phase, we come from a higher workload, right? So talking about four or 568 minute interval duration, your Krebs cycle is running at an adaptive speed, because the interval was long enough. So let’s say your interval, you’re on phases at 300 watts, just to stick with that example. If you’re on phases at 300 watts, after, you know, after a minute, your Krebs cycle turnover rate is definitely at, you know, up to speed with that. So now when you go down, it’s not a problem that it’s it’s too delayed, so to speak, to catch up, it’s coming down from a higher level. So therefore, the ability to push lactate into that is, you know, it’s not an issue, it is actually defined by, you know, the intensity of your resting period. So again, if you don’t keep some energy flux, if you don’t keep some power output, you know, during the resting phase, then your aerobic metabolism, your Krebs cycle, will, after a certain time come down to close to resting level. And therefore the ability to push lactate into that for combustion is relatively low. And that’s something Yeah, I mean, don’t don’t need to go into the marketing stuff here. But that’s something VFP like like that is, for example, one of the key metrics, or one of the key graphs, which most of the inside, using coaches appreciate a lot that you can see average power output, how much additional lactate you can push into the Krebs cycle for recovery.


Trevor Connor  44:27

But this goes back to what you were saying before, which is what I’m basically agreeing with is when you’re doing this type of interval, and you get to the rest phase, you want to keep pedaling, you certainly don’t want to take a 32nd recovery, but I would personally say don’t take a 10 minute recovery either. But more importantly, if you do that eight minute threshold interval and then go sit in the grass for 10 minutes, not the way to you’re not prime for the next interval.


Chris Case  44:55

From a from a practical point of view, for those that like to do Maybe a hill repeats eight minute Hill repeat intervals, that threshold, you’d ride up, you do the eight minutes you turn around, maybe it takes you a quarter of the time to get back two minutes. And then you turn around and you hit the next interval. That’s, that’s a good sort of rule of thumb here, when we’re talking about this type of interval,


Sebastian Weber  45:21

would you say? The problem is that in the downhill, you’re maybe coasting or not pedaling, right? So you’re very similar to sitting on the grass here, in terms of muscular load. So in this case, you might want to ride a little bit, downloads of that, you know, few minutes before you before you get to climb again, we use it for example, even the range like even pacing and time trialing, like, you know, beckons highroad days and stuff HTC whatsoever. We we use that in the time trial, even reminding our athletes to keep pedaling on the downhills also at a decent power output. And the issue is here is when you just do it by feeling in most cases, you pedal too easy. Like, especially for professionals of workload they have so intensity, where they combust the highest amount of lactate, are the highest rate is actually a decent intensity. Therefore, you need to remind your guys to it, but it works really well. So you can you know, not even use it in training, you can use this information as this knowledge also, to make a better decision on your pacing and a time trial.


Trevor Connor  46:28

We talked about there’s two types of these long intervals. Before we jump into that all out. When we’re talking about this threshold, these intervals where you’re trying to do them right at threshold, what do you feel feel is an appropriate length recovery and an appropriate intensity for the recovery?


Sebastian Weber  46:49

If it’s right, that’s threshold?


Trevor Connor  46:50

Yeah. So let’s say you’re doing an interval somewhere in the five to 10 minute range, and you’re doing it right at threshold.


Sebastian Weber  46:57

But honestly, then, you know, it is physiologically speaking from the muscle energetics point of view, it’s not that important, my personal opinion is I would, you know, I would have the guy doing something like five minutes at whatever 50% of threshold, as a rule of thumb, that’s maybe more arrest, you used to drink something and maybe take up the, you know, sip from a jail or something, and not really because you need to restore a lot if


Trevor Connor  47:20

it’s right at threshold. So interestingly, I think I mentioned earlier that 2019 review that said, there’s not a lot of research on on recovery, length and intensity. But the one thing they did mention, is the recovery, the exact length for this sort of work. isn’t that important? As long as it’s long enough? So he basically said, if you take a 32nd recovery, yeah, you’re probably in trouble on that.


Chris Case  47:48

Well, you guys are agreeing, then. Absolutely. All right,


Trevor Connor  47:52

you’re my The thing I would just add is just that again, you do 510 minutes without pedaling. Yeah, you have to be ready for the next one. So I generally tell my athletes somewhere in that, for the recovery, two to five minute length, depending on the length of the interval and just keep pedaling. Mm hmm. And what you agree, intensity, probably we don’t need to give a specific intensity for the recovery. But pedal,


Sebastian Weber  48:20

yeah, put some powers and for me, good rule of thumb is 50% of your of your threshold power, I would maybe not go a lot below 40%. And I think an upper limit, you know, not naturally like you would not necessarily have your recovery at 80% or 90% of the threshold. So this is an issue. Most likely what what happens is it’s that it’s very, very easy. And I mean, again, in this kind of exercise, if you do rest for five to 10 minutes, you could, you could certainly have a few minutes without pedaling there. No problem really, I personally don’t have many athletes that didn’t have many athletes that would do these kind of, of 10 to 15 minutes threshold work. Some, some do. And some do have really good experience with that in most cases, we would break it up into shorter intervals and therefore shorter rest, or spice it up for some you know, especially cadence work or ism changes work or something like that.


Trevor Connor  49:17

I will say even when you’re doing it a threshold and as you said when you hit the end of the interval you can keep going I will rarely ever give an athlete over eight minutes. I’d rather just have them do a little a few more with with some haven’t haven’t been recoveries.


Sebastian Weber  49:33

One thing I have to admit though, is that we did it in the past more from a tactical absorbed psychological point of view. For example, is this this Tony Martin to get the interval in, which refers to try to mimic the length of whatever a prologue or try to mimic the length of off a specific stretch of a snippet and is whatever championship Time Trial course right and it has whatever is trade, which might take him 20 minutes, right, a straight road or something, then he would do that. And then again, maybe look more for the position on the bike and these kind of things. So the justifications, and to do such a long interval was more from Okay, that’s the race coming up and a couple of weeks. And from a practical point of view, we want to, you know, we want to just try to stay focused on the intensity and be clean with your position and aerodynamics, these kind of things. So, I have to admit that Yeah, then then we did whatever duration needed, so to speak to accomplish that.


Trevor Connor  50:32

Yeah, we are agreeing a lot in this podcast, because as I said,



so far,


Trevor Connor  50:40

because as I said, I will rarely give longer, but that if I have somebody who’s a time trial list, the way I explained it to them is I’ll use the shorter five or eight minute intervals to build the power. But then as we’re getting close to a key race, or when they’re regularly racing, I’ll do some longer intervals with them, which is I call it teaching them how to use the power. So it’s more about, okay, let’s say you got your threshold up to 300 watts. Now, I want you to do that longer interval learning how to pace how to do that. 300 watts for that length of time? Yeah, yeah.


Chris Case  51:17

Yeah, let’s stop being so boring. Let’s talk about a different type of interval here. Let’s talk about the all out. But long interval, say it’s a five minute interval, and it’s full gas.


Trevor Connor  51:30

And this is just, particularly in the North America, the common nomenclature for this is is vo two max intervals, right? So they tend to be four or five minutes and like, and they’re all out.


Sebastian Weber  51:42

Yeah, maybe we should do a podcast one whole session about why you causes the automatic centella.


Trevor Connor  51:49

They’re there, there’s a whole bunch of terms that just have become the terms that you could really dive


Chris Case  51:54

into. Well, we won’t, we don’t have to refer to them as such, but let’s just define them as five minutes in length and all out. Yeah,


Trevor Connor  52:04

yeah. So I’d say four to five minutes. And it’s Yeah, you should be bleeding from the eyes. But


Sebastian Weber  52:10

okay, so let’s assume you do that. And let’s don’t touch on it. Why you do that? Or maybe you don’t you don’t do that. Talking about the recovery, right?


Chris Case  52:19



Sebastian Weber  52:20

the issue is here. And that’s, that’s the main issue with recovery periods is that you are maxing out different systems, right, you’re maxing out your creatine phosphate stores, because those will be depleted at the end of this exercise, you are maxing out your pH levels in terms of d decreasing those, you are most likely maxing out your your lactate concentration, which you can handle so to speak simplified, you’re maxing out your your your view to obviously like, you know, that’s that’s part of it. And the issue with the rest period is that you have now different systems you need to recover. And they have different time kinetics, how long it takes them to recover, and they have different intensity at which they recover the best. And this becomes the complicated thing here so to speak. If your intention is to bring back all systems to full recovery, which is needed, if you want to at least try to repeat the same exercise, right. So if let’s say, if you create a session here to be more precise on what kind of intervals you’re talking about, if you create a session where you say I used to, I used to go the first one full out. And then I used this power as the reference for the other, follow for the following three, four, I don’t know how many reps you want to do, and use this as my reference point and try to hit the same number. If this is what you’re doing, then you need to recover and restore all those different systems. And again, they recover a different duration at a different intensities. And this is the tricky part here. Again, going back to that. Dr. Seiler study. Interestingly, they didn’t really find a difference between two and four minutes. And when they had a group self select the recovery lanes without be able to see a clock or anything. It averaged out to 118 seconds. So basically two minutes.


Chris Case  54:20

Yeah. And this goes back to our discussion about the perturbance. And what what Sebastian is saying now that one system takes X number of seconds or minutes to fully restore itself, another system takes a different length of time, and you might want to have them all restored, you probably do want to have them all restore, but if you don’t do them the right way one might be fully restored, another might be 75%. restored there. So that’s why it gets pretty complex. That what we’re saying here?


Sebastian Weber  54:50

Yeah, it is. It is pretty complex. But on the other hand, you’re talking mostly about two systems here, right? For the studies that you just cited. You’re just talking About the phosphocreatine system, and you’re talking about the lactate system itself was a pH values. And z, the results you just cited or summarized here are not really surprising. Because in this study, z intensity and z in the recovery phase was compared below. Like the, it was basically like a fast walking, right,


Trevor Connor  55:25

right. This was runners we should mention, yes,


Sebastian Weber  55:28

yeah. Okay. So this was a runners and they ran it five kilometers power, I guess for the recovery. It was and this is I mean, this is a good walk, right? So at this intensity, the rate of lactate recovery, so the rate per minute per second whatsoever, how much lactate you can clear from your system as a muscle is relatively low, especially in this population? He heads they’re walking for two minutes or four minutes. Doesn’t change a whole lot here in terms of the lactate. Right? Right. It’s not a huge difference. We are maybe talking about half a millimeter or something ish, like ballpark. And what happens at this low intensity is that you have the recover your creatine phosphate stores in the first approximately one and a half to two and a half minutes, depending on you know, mostly depending on how good you are aerobically. So how big is your aerobic engine? How big is your view to max. So therefore, it is no surprise that you don’t see a difference between the two ends have fought no significant difference, because between the two and the four minutes recovery, because basically, the recovery of the creatine phosphate system cannot change significantly between two and four minutes. And the recovery of lactate will change, but the but the impact the effect of the effect of that is rather small. So this is why the directed or prescribed recovery phases shows this pattern. And then the self selected one, the self selected one is also refers to the same mechanics basically. So self selected. One is because you feel recovered, or you feel better when your creatine phosphate system system is recovered or is replenished, you know, we just talked about before talking about long intervals that, for example, as a pro cyclist, but also an amateur recreational cyclist, the self selected intensity for recovery is most likely never too hard. But if so too easy, right. And that’s the first thing that happens when you do a heart interval. And your best recovery rate for recovering lactate is, let’s say, 180 watts, your threshold is 300 to do your threshold intervals. Or even after those four or five minutes, it doesn’t feel good, it feels pretty ugly, so to speak, to jump from 300 400 500 watts, back to 200, it feels much better if initially you just stopped pedaling, right, or just pedal of is 50 watts or something. And the reason for that is because the force you must create is related to the creatine phosphate content. So when you replenish your creatine phosphate, and again, this process is I mean, it’s not linear, right? But it’s, you’re close to the maximum replenishment of creatine phosphate, again, depending on your on your oxygen kinetics of your to max approximately after two minutes. So after that time, you feel strong again, you feel strong, and everyone’s natural is that, you know, athletes, the athletes, the the, you know, repeats in the next interval or are more more inclined to, you know, to, to restart again. And if you want to have an idea on how this feels like or what’s going on there, just imagine. And this also tells the story about how crixus this processes, imagine you’re writing very, very hard, like in a bunch of something, right, you almost writing at your limit. And it’s about to do the attack, it’s about to go out of the saddle, and push hard for just a few reps here. Imagine doing this when you on your limit versus just stop pedaling for two seconds. Right? If you just leave out so to speak a few pedal strokes preparing for a sprint or just a little attack, you will immediately feel a little bit stronger. And this is the fast first phase of creatine phosphate recovery. And again, the force that you can produce and therefore the torque and which is obviously important and acceleration depends highly on the phosphorylation of the muscle cell which is creatine phosphate, restore hydration. So yeah, these findings make absolutely sense in terms of muscle energetic,


Trevor Connor  59:54

and I’m gonna just say it was you said if you do these intervals, you feel better if you just stopped counting. And afterwards and fully rest, for the reason I don’t like giving these intervals to my athlete is I’m going to take that a step further. And so you feel better if you do these intervals, right? If you run into the woods and get ready to launch. These are not fun. And I’ve actually, I get the sense you do not like this type of interval. I would love to dive into that just for even a couple minutes.


Chris Case  1:00:23

Yeah, educate the North American listener as to why you don’t like these why these are not effective. And you’re in your mind. And that’s the sense I got as well.



I didn’t say that I don’t like No, okay.


Sebastian Weber  1:00:36

No, I’m just, you know, I just struggle. It’s just difficult to talk to people about via to max intervals. Because there’s two, there’s two assumptions in here. One assumptions that most people have when they hear via to max and abbazia. They assume that this is the only way or the one way to increase your viewer to Max, which isn’t. Right. And then the second question is, and we had this running, running up for this for this recording today, what is the intensity? What is the intensity that describes the automatic and this is where, you know, there’s a lot, there’s a lot of misunderstanding? And therefore, I’m just very careful about these intervals. Because I first would like to understand what are we talking about here? Right? Are we talking about the intensity, the power output, the energy turnover, that equals vo two Max? Or are we talking about an intensity at which you reach view to max in any kind of incremental step test REM test all our test whatsoever? Right? Like, is it? Is it a power output associated, which this is your recording your view? automax. And whatever setting, then we are linked in this definition via link to the testing protocol. Right. So that’s my, that’s my difficulty here. And then in terms of doing it in terms of doing it, well, I’ve no direct offense against it. I’m a little bit biased here in terms of when you do these kind of intervals, this professional athletes and I have I’m, I have to admit that. Obviously, I’m biased here, my mind is more resist, it’s no offense, it’s just because that’s what I did. And in the past years, I mean, I’ve coached more amateurs beforehand, buttons up in the recent past. And anyway, when you do these kinds of intervals, that you really go on out for four or five minutes with professional athletes. It’s a very, very uncommon thing. And the possibilities that you crack your athlete is quite high. I know that it’s different. There’s amateur recreational athletes. And most likely most people don’t really go all out like that don’t, maybe you only go to 90% or whatever, of maximum. But that’s why, yeah, that’s why I’m a little bit careful with that. Right? Because the high intensity and maxing alto duration is to say the least a difficult combination, I would say,


Trevor Connor  1:02:56

yeah, that’s actually demo, we’re agreeing again, as I was hoping to add some a little bit of back and forth, which would have been fun. But the issue I have is I do agree with most people can’t get into the lab and do a vo two max test. So when you talk to people about vo two max power. The the common definition is it’s your peak five minute wattage. And if you think of it that way, anybody who has gone out and done a proper test all out five minutes, hit the highest power, you can for five minutes knows you’re then dead for the next 20 minutes or those efforts. So to do that once will absolutely make you suffer to then say okay, now go do five by five of that. Nobody can do that. Yeah, so you’re always doing something a little below and for a lot of people because of how much that hurts, it tends to, in my opinion be too much below and then you’re in this kind of in between place. Right, right. Right, right. I also personally don’t love it because you’re generating a lot of power aerobically. But as you said, you’re also generating a lot of power anaerobically. And it’s kind of in between, I would personally rather have an interval that really works. lactate metabolism really works your aerobic system and then have another interval that just hones right in on that anaerobic system.


Chris Case  1:04:23

Yeah. All right. Well, since these intervals aren’t our favorites, should we move on to a different kind?


Sebastian Weber  1:04:28

But did we did we answer the question how long recovery and what well, I put? No, we didn’t really right. So so let’s, for those who will still want to do these? Let’s answer that question for them if you want to get at least a chance to repeat the same effort again. So again, I’m talking about the most extreme version may be that you take the first interval as a reference point and then did it and then you try to replicate the power output right? eventually cause a problem we can we can talk about wises is maybe not possible if it’s the first One was really all out. But anyway, if you want to do that, as this is a setup that you want to do, then you would at least need to account for enough time to recover the lactate, or, more precisely saying to combust the lactate which you have accumulated during the effort, this can easily be 20 minutes for a full recovery, and you need to recover your creatine phosphate system, but you just, you know, have to, as Trevor said, sit in the grass for two minutes as we, you know, seen as an example, in the silo study, the closest you can get ballpark or rough idea is the closest that you can get in terms of full recovery is writing for giving a ballpark here, depending on how quick you can recover them, or how quick you can use the lactate, which you accumulated, and how much you accumulated, say somewhere between 10 to sorry, that’s the range 10 to 25 minutes, pedaling at 50 60% of your threshold power, or 60 to 70 in advance this ballpark, depending on your metabolic profile, and then followed by a little bit of full rest, that’s your best shot to replicate the same intensity again, because then you have at least those two system completely recovered. And that I must say is probably very unlike what most people do do, right. But what most people would do five minutes


Chris Case  1:06:25

all out, quote, quote unquote, all out, they probably rest for five minutes at most, and then do their second effort. And third, right?


Sebastian Weber  1:06:35

And maybe, and maybe my assumption, maybe my assumptions that the first one is 100% all out and then you’re trying to replicate is is not what’s short of what most people are not doing. Right. What might be interesting, though, or, you know, because what just Trevor said, like, you know, I’ve tried to set up an interval session, which is trying to target as good as possible isolated one energy system, what you and what we’re going to see when we talk about the more high intense stuff, the shorter intervals, is set your recovery lengths. Because of your recovery length, and how you design the recovery in terms of duration and intensity, will actually change your muscle metabolism from one interval to the other to the next to the next to the next, the metabolic stimulus that you get from the first interval. And how’s he How is your how your power output is produced in terms of creatine phosphate lactate aerobically will differ dramatically from the last one. Right. Right. And so that’s something again, why why is difficult to, you know, to cause these things to to max intervals, maybe, or to put that any kind of label on it, so to speak, right? The first one is not the same as the last one.


Trevor Connor  1:07:51

So I think my recommendation with that big Asterix of I don’t really prescribe these, the only time I ever prescribe these to an athlete is let’s say they have a target rays coming up. That’s a short circuit with a four or five minute climb, and then you just do this once or twice for some specificity. Nobody’s gonna do a prescription of five by five minutes or 20 minute recoveries, right? Take it take a long time to do it. So at that point, I’m going to go forget about the lactate system, let the least phosphocreatine recharge, you’re going to be there in about two minutes. So two minute recoveries, and just ask the question, why are you doing these intervals? I don’t like Yeah, yeah. Shall we move on to what we’re considering here? midlength. intervals, one to three minutes. I don’t think I’ve ever seen somebody do a three minute interval. I see two minutes all the time. I’ve rarely seen three, do you prescribe three minute intervals? Or anything in this length?


Sebastian Weber  1:08:48

Yeah, sometimes. Okay. But why don’t? three minute intervals? There you go.



very specific.


Sebastian Weber  1:08:57

I mean, again, if you tell me the time, then you have to tell me the intensity. Right.


Trevor Connor  1:09:01

So that’s a good question. And let’s talk and yeah, you know, obviously, one minute versus three minutes all out is very different. So this is we get three


Sebastian Weber  1:09:14

different metabolically speaking into five minutes all out. Yeah. Right. It’s, it’s


Trevor Connor  1:09:20

like it’s similar, right? You have a chance to deplete all your systems or max out all your systems, I should say more. Exactly. Right. You just do two minutes sooner. So why don’t we then obviously, like, we could just take this and do an entire podcast or probably a couple podcasts in this. So why don’t we simplify this down to two to three minutes all out? So as I said, that’s going to be higher intensity than even your four to five minute all out intervals. So what are you Why don’t we talk about a little bit what your what energy systems you’re hitting with these intervals and then talk about appropriate recoveries?


Sebastian Weber  1:09:58

Yeah. So basically When you let’s say, to even find a bigger contrast here, let’s say you do two minutes all out, versus five minutes all out. And maybe not, that’s not even talking about doing this interval, just use it as a single effort. Right? metabolically what’s happening is basically the same thing, you should, in two minutes, you should hit view to max the differences in five minutes, you may be right at your max for 30 seconds, 45 seconds depends right? A little bit in a two minute. You may be hit vo two max after 100 seconds or something. So 22nd data is over anyway, maybe you just hit it, you know, five seconds before it’s finished. So depending on how quick your oxygen kinetic kinetics are, again, also it’s that is a marker on how strong you are aerobically. So it says some correlation, or a strong on some correlation, visual view to max. So long story short, if you have a low of your max, you might just hit view to max at the end of this two minute interval, if you have your two maxes about 50 or 60, in that range, or higher, then then you will most likely hit view to maximum This is in two minutes, at least on a muscular level. But most most cases also measured at the mouse piece. And then the other the other, you know, you deplete your creatine phosphate stores and your are accumulating a lot of lactate, the total lactate levels can differ a little bit to as a five minute one. But not not a not a huge amount. So it’s not like that you end up at 20 millimoles, after five minutes, and you end up at 10 millimoles. After two minutes, that’s not the case. You know, they’ll be in a similar ballpark, this and whatever a few millimeters actually. So it is not that different. Even if you again takes the biggest contrast here is endless ranges, two minutes versus five minutes, it is not that big of a deal different to the five minute effort. And then obviously, if it would be three minutes or something becomes more and more similar in terms of what happening metabolically in the muscle.


Trevor Connor  1:12:04

But these are also very tough. They’re very damaging, you’re probably using a little more anaerobic metabolism. Let’s talk about the rest. what’s what’s appropriate intensity, what’s appropriate length,


Sebastian Weber  1:12:19

because you’re maxing your glycolytic system, so to speak, and you’re maxing out your creatine phosphate, it comes basically back to the same thing, you need several minutes of recovery at an intensity where your lactate recovery, your lactate combustion is the highest. So what we call the lack of pyruvate. So how much additional lactate or pile that you put, you could push into the Krebs cycle, which is depending on your profile somewhere between 55 to 75 80% of threshold. So that’s the intensity you should do for your lactate combustion for the lactate that you accumulated. And then depending on your straining, status, professionals can clear at the rate of approximately one a little bit higher millimoles per minute, and they may be only reached 10 millimeters, or 11 or 12. So they need to go 10 minutes ish. And if you are a recreational athlete, you maybe only can you know clear at a rate of 0.4 millimoles per minute, you may be reached 16. So therefore, you have to go significant longer. And then because you’re still running at a decent percentage of your threshold, you’re not going to replenish your creatine phosphate system entirely. So there you go again, coasting or sitting on the grass, for two minutes ish or longer to replenish that. So the this is the type of recovery you would need to do is very similar to the five minutes. And again, I get it that most people will not do this most likely, it will be most likely shorter and will most likely look different. If you’re not, if you’re not sure if they’re not include two different intensities, like a decent high one, because 60 70% of FTP is most likely what most people are not doing and will most likely not have a total rest phase for two minutes. But then on the other hand, most people will not go flat out maximum for these two minutes. But maybe they’re talking about whatever 95% or 90% of their of the maximum here,


Trevor Connor  1:14:20

I’ve always looked at these is you really need to make sure before you start each one, you have some recharge of that anaerobic system. So you’re really recharging the phosphocreatine. And these intervals, again, they should really hurt. I used to do two minute intervals. And the way I would do them is on a climb. So just two minutes as hard as I could. And I would have about enough energy at the end of that two minutes to just turn around. And then I would coast down that hill and not pedal.



Mm hmm.


Trevor Connor  1:14:53

Right. Because that maybe they’re hurt.


Sebastian Weber  1:14:55

Maybe to make it more applicable for for the listeners. Then maybe we should Maybe you should, we should pick one example of, you know, the resting period. And use this as an example to talk about. So based on your guys experience, how you use it, how you prescribe those intervals, what would the recovery look like in terms of duration and intensity?


Trevor Connor  1:15:18

I see these intervals often been a, no, I’m going to completely contradict myself. But I often see this type of mid length interval being a one to one recovery. So it’s a one, if you do in one minute, you do a one minute recovery, if you’re doing two minutes, you do a two minute recovery. If you do three minutes, you do a three minute recovery. I look at it more as the what we were talking about before, it takes about two minutes to recharge that phosphocreatine system. So to me, a two minute recoveries about appropriate. I tended, as I said to do two minute intervals. So I did do a one to one ratio. But if I was doing a one minute interval all out, I would probably still do a two minute recovery.


Sebastian Weber  1:15:56

And so how do athletes replicates and the same power output during zentiva? Or is that drifting? I am a fading away.


Trevor Connor  1:16:06

So I always try to target specific energy systems. So I’m a big believer, when you do interval work, you want to try to maintain constant power, like the you should, across intervals have the same power. I don’t like looking at intervals where somebody does 400 watts in the first interval, 300 watts or 350. In the next interval by the final interval, they’re doing 275. To me, right? That’s all over the map, then blowing up. It’s not quality work. Yeah.


Sebastian Weber  1:16:36

Okay, I see. How do you feel, if you do that stick to that example of when, when you do two minutes hard, close to maximum, let’s call it right, because if it would be maximum, you could not repeat it after two minutes. If you do two minutes close to maximum effort, and then have a two minutes rest, that is too short, to recover your glycolytic system. or more precisely speaking, in the next upcoming interview, glycolytic system will not be able to produce the same amount of energy for the same four forces to two forces two minutes. So therefore, percentage wise, more energy has to come from xerophytic system and from the creatine phosphate system. And because creatine phosphate system is really limited, and there’s not so much power you can get from it in a two minute intervals, aerobic energy contribution is going to increase from one interval to the other. And this then also explains the mechanics, why you cannot do it being at your maximum possible power output for each repetition. Why you if you want this way, asked for constant power, if you want to go at constant power, you would need to go a little bit above the absolute maximum. Because, you know, if you’ve maxed out your aerobic system as the first one, and maxed out your glycolytic system and maxed out your creatine phosphate system, and then in the next one, one of those systems is not recovered enough. So you cannot get the same energy cannot get the same power from that in the next interval, then your power output would have to drop. So in order to repeat the same intensity for a set of I don’t know what 3456 I don’t know how many intervals to set intensity is a set power pitfalls, the interval itself cannot be the absolute maximum.


Trevor Connor  1:18:22

Which is why when I prescribe it to an athlete, I usually tell them if you’re doing it, right. So talking right now about, say the two minute intervals two by twos I tell them, you’re doing it right, that first interval is is should be really hard. But you should finish it going. I could have gone a little harder or feeling could have gone a little harder. Yeah, when you get to that six, one, I want it to be at the same power. So I’m sorry, I was given a set of six. When you get to that six one, you should be saying that was death?


Sebastian Weber  1:18:51

Hmm. Yeah, that’s it. Yeah. Don’t want to do one more.


Chris Case  1:18:56

Given the fact that after that first one, you’re not going to if you’re doing that, if you’re only using two minutes as rest, that then you’re having to generate energy in different ways for the subsequent intervals. Is there an advantage to that? Are you actually adapting in some way based on that?


Sebastian Weber  1:19:18

Well, you certainly adapt differently because the training stimulus is differently. So you certainly should adapt differently, right? If there’s an advantage, obviously, it’s a question of what what was the aim for the training Mm hmm. So, if you are, if your aim is that you that you trigger your glycolytic system to the maximum in each intervals and you failed, if your aim is to whatever max out creatine phosphate and use a high aerobic, you know, energy contribution as a training stimulus, then you succeed it. Yeah,


Trevor Connor  1:19:56

you actually bring up a really good point. That I can find any more cowbell, we should have brought this up earlier that you make a really good point that when you’re doing interval work while your power, let’s say you do intervals where they’re all at the same power, you might go well, they’re all the same. But actually, if you look at your energy contributions, how much energy is being contributed anaerobically versus aerobic Li, from the first interval to the last interval can really change. Oh, yeah. So back when we’re talking about the longer than four minute intervals, there’s actually a fairly well researched type of interval that I really like, which is five by five minutes with one minute recoveries. And one of the theories behind that is, with the one minute recovery, you’re not really allowing yourself to fully recharge anaerobic energy stores. And it means that as you get to those later intervals, and you’re trying to generate the same wattage, you’re trying to generate it almost entirely aerobically. And and that’s what I love about those intervals is if I’m trying to hit the aerobic system, let’s burn up your anaerobic energy not allow you to fully recharge it so that you have to rely on robot pathways.


Chris Case  1:21:15

I mean, I think in this discussion here, secondly, also brings up a very good point, which is having a known purpose for what you’re trying to get out of a particular workout. And and sometimes it’s obvious, perhaps sometimes it’s a little less obvious what you’re doing. And hopefully, this discussion, shed some light on what is actually happening.


Sebastian Weber  1:21:34

Hopefully, what became clear here is something that no offense, but I assume most people don’t really think about a lot, or enough is that, yeah, I mean, we talked about it, you have your view from accidental eyes, are you talking about some kind of intervals. But when you do this, you only always talk in most cases, at least, about the intensity, and the duration. And you already put a label like view to max or something on it. But actually, what’s going on in this intervals? Depends highly. And this is I guess, why you do this episode is depends highly on the recovery. So you can do like, just go back to the studies astrologers means you can do these five minute intervals. If you change from one minute rest to 10 minutes, it looks totally different. It looks entirely different. And the same, you know, sound stupid, but it’s obviously, I mean, it’s pretty obvious. If you change the resting intensity from whatever, zero watts to 300 watts, still, it’s one minute, but it also changes a whole lot. And, and, as you said, People prescribe an interval training, right? They go and say I want to do vo to max Pandavas. And forget about maxing it out, let’s say we do it at 90% of what you could do for this five minutes. I think they’re very, very important take home message is here is that the energy systems and the training stimulus, the change Vassilis roses intervals, the first one compared to the last one. and everything in between, and how much they change depend on how you design the recovery period. And I think most people are under the impression or it’s the same duration, it’s the same intensity, therefore it’s the same training. And it’s not.


Chris Case  1:23:21

that’s a that’s a great way, we should have that at the very beginning of the episode to set the stage for this whole discussion, because that’s exactly what we want to address. And we’ve been addressing, right.


Trevor Connor  1:23:32

And it’s such a good point, because as you said, you can look at the intervals and say the power was the same every interval. But the the energy contributions can be so different.


Sebastian Weber  1:23:44

vastly different. Yeah, that’s because again, all the systems recover in different kinetics and a different power output. And, yeah, you need to know, you need to know about this to really understand what’s going to happen in the next hour. Which is, by the way, one reason why all these you know, what’s it called dynamic w prime or w prime recharging, so to speak failures, because the, because the depletion process is quite simple. And you can almost calculate or model linear, but then the recovery or replenish process, again, it’s two different systems, different kinetics, and a different power outputs. And this is one of the reasons why, why, you know, w prime replenishment is something that it’s not really representing or replicating the true recovery and it often fails like you know, predict you’re recovered and even you’re not and you cannot replicate the same, the same effort again.


Trevor Connor  1:24:47

We gotta admit, we haven’t been hiding our thoughts and things like what prime there’s certainly a value to it, but there’s also some issues. But one thing that’s certain is there has been a lot of effort put into measuring that drop in the anaerobic metabolites are that anaerobic capacity to figure out optimal recovery links. Dr. Steven Chung, a professor at Brock University and the head physiologist for exert training software has been working on one of these metrics.



I think so many people overlook that process of recovery. And, you know, any interval can be made harder, by doing more intervals by doing the intervals and harder or shortening the recovery, right, because if you do the next set already at a fatigue state, it is going to be much more of a training stimulus. And that’s actually one thing we’re able to quantify and, and design workouts in exert with, it’s to be able to have workouts where you, you time your recovery, not just based on time, or even on heart rate, but based on our motto of your maximum power available, which is really analogous to fatigue. So we can have workouts that deliberately take you to a set level of fatigue, allow you to recover to another kind of level of recovery, it may not be full recovery. And then that’s when the next interval starts. So I think that is a huge factor in kind of designing quality intervals, it’s again, not just the intensity of them, not just the number of them, but also in the in your recovery. And I think too many people kind of overlook that. They either overlook that. And, you know, again, if you’re doing a sprint workout, and you’re where you want to really generate max power. After maybe two, three minutes after sprint, you start feeling okay, I’m still pretty good, but yet, you’re still not fully recovered. Right? Whereas you, but many people kind of, Oh, I want to get in more sprints, I’m already feeling good. And you know, surprise, their next sprint and or their six sprint isn’t as strong as a result. Or, you know, whereas you really want to balance that and take that full recovery. And again, I think one of the strengths of our software with exert is that we can tell you exactly when you have recovered to kind of the appropriate amount for that workout. And you can also design workouts to target specific levels of fatigue. But to get back to your original question, I think it is huge. The recovery aspect, just like recovery from an overall workout, too many people overlook that I think people tend to overlook that during an actual workout itself.





Trevor Connor  1:27:46

now, so knowing that you could probably write a whole book about the rest periods. Any couple quick tips for people on how to pick their their recovery length,



I think the it really depends on your focus and the target of your workout. Again, if it is a pure sprint workout where you want to be as rested as in between sprints, you want to really err on the side of having a long, long break have much longer than you think that you are, you know, beyond where you feel that you’re ready for the next one, because your whole target for that is to generate Max Max power, and from as fresh a recovery level as possible. Now, you know, whereas if you’re designing a workout that is really simulating, for example, a cyclocross race or a crit race where it’s really incomplete recovery in between, then you want to kind of have that in your in your workouts, too, that you may have already get to, uh, you know, do a first set, and then maybe you want to, you know, Target, especially as you get closer to your race, you know, shorten your, your actual recovery period to really simulate that ability to go hard over and over and over again. So I think there’s no kind of one single rule, but I think it really comes down to what you were trying to achieve with that particular workout.


Trevor Connor  1:29:30

Now we’re getting into the sub one minute intervals, and a very unique one that almost the recovery is more is as well, let’s say the recovery is as critical in these prescriptions as the interval length. This is the devadas and where people think about it a little bit, I think I think you’re right, Sebastian, going back to your point that a lot of people don’t understand or consider the Should I lay down should I be writing at 50% max You know all that but but here I think at least from my point of view, it seems like to bottas people get it that the the shortness of the recovery is a critical component to the interval itself. And the one minute background on this is and we’ve had an episode where we really talked with you about what prime and anaerobic capacity, which often people use interchangeably, they’re, they’re not the same thing. And we can also have the conversation about whether there there’s actually something physiological there. In either case to body read all his research, he was trying to figure out a way to deplete what he called anaerobic capacity. And as we said before, he discovered trying to tell people to do five minutes all out is really hard. But if he gave, so his original protocol was 2010s, but the more popular one now is 4020s. But he found if you gave a short all out effort, with a recovery, that’s half the length, he felt that completely deplete your anaerobic capacity.


Chris Case  1:31:02

And in the original studies of Dr. Tabata, was it 20 minutes? total absence to it, sorry, sorry, yeah. 20 seconds, full gas sprint, and then 10 seconds of coasting, or, or how did he define that?


Trevor Connor  1:31:22

Deal? That’s a good question. I’m pretty sure it’s 10 seconds


Chris Case  1:31:25

coasting. Yeah, yeah.


Trevor Connor  1:31:27

So Sebastian, What’s your feeling about this,


Sebastian Weber  1:31:30

those kind of intervals are a very smart way to design an effort or an exercise and and maybe the best, the best way to understand it is basically it is almost like like a 10 minute block, but then you have these little drops of intensity, so to speak, within this 10 minutes, and like, if you do it, like we would traditionally do it in cycling, you know, for like 10 minutes like what right. So, so anyway, what is happening as obviously, or because of the short duration of the recovery, and because of the intensity, going back to what we said before, you cannot expect a lot in terms of recovery of the glycolytic system, right, your your your lactate levels are not really drop in 10 seconds, right? And your and your, your pH levels, they’re not really changed a whole lot. That’s not entirely true, because they depend also on creatine phosphate. But for the sake or for the reason of changing your lactate system, your pH does not really change. What is going to change though SV. Already briefly mentioned talking about what happens if you stop pedaling before sprint for just a few seconds is you’re replenishing creatine phosphate at you know, in this 10 or 20 seconds recovery. That’s what base happens. But especially as you said, You’re coasting, you’re not putting out any power output. So you’re replenishing your creatine phosphate. And then you are using, obviously, this replenish creatine phosphate, especially in the first seconds of the next node phase of the next on phase of the next interval, basically. And what I think the genius part here about this is that it’s important to understand or important to point out that the recoveries or you know, recovery, recovery of creatine phosphate can only happen using the aerobic system. So the aerobic energy mat was the only way how you can recover creatine phosphate. So what happens when you do that, think about it, you do the 20 seconds or 40 seconds heart interval, high intensity, right? It is obviously so high intensity that it will trigger your view your view to your aerobic system to go towards maximum. So first one is obviously to show it right, you’re not reaching your view to maximum 20 seconds, right. And then in the off face, the aerobic metabolism is working to replenish your creatine phosphate that you used and there’s 20 or 40 seconds effort. So your aerobic system is never really going down a lot because it’s maximum triggered, or stimulated to raise to increase in the face. And it’s used in the office to recover creatine phosphate. And so, when you when you For example, look at the auction uptake in zoes antivirus when you set them up right and this is a more dedicated question, what is the right intensity to do that? Obviously, only 40 on face because the officer faces just nothing or just coasting. When you do it the right way. You will find yourself writing very close for view to max for the better part of the full set of intervals and you will find yourself writing at a view to max You will not be able to replicate from a constant load, just by browsing. That’s, that’s why I say you can think about it at a constant load blocks where you have these little dip scissor drops and power output, which are just basically allowing you to continue. And because of the, because of the oxygen kinetics, and because of the, you know, recovery of the creatine phosphate youview to Max, it’s not going down significantly, like it would do in a 20 minutes rest, obviously.


Trevor Connor  1:35:28

So therefore, you’re writing close to the automax for several minutes. And that’s quite impressive. I think the other thing that’s also important to point out is that there are the phosphocreatine is restored in two stages. So you’re taking advantage of that first stage where you get a lot of it restored, but you’re not fully restoring or replayed in the phosphocreatine. And I bring that up because I often hear people talk about devadas, especially if they’re doing the 2010s as Oh, I’m doing a whole bunch of 22nd. Sprint’s with 10, second recoveries, and I was go, if you’re taking a 10 second recovery, you’re not doing a sprint. Mm hmm. You’re going hard, but there ain’t no way you’re doing 20 a bunch of 22nd all out sprints with that sort of recovery.


Sebastian Weber  1:36:12

Yeah, it’s 300 watt sub max sprint, right.


Chris Case  1:36:15

Well, is it is it worth clarifying how two bottles should be properly executed then? Are people seated? Are they standard there? Are they launching? Are they are they hitting a particular power? Or are they just going by feeling because it’s so you know, intense?


Trevor Connor  1:36:34

My answer is a lot of bargaining with yourself to keep going


Chris Case  1:36:39

yeah, psychological component here is is something we won’t dive into but it is pretty critical for these


Trevor Connor  1:36:48

What are your thoughts about shins? even mine is the should really hurt when people tell me what why did you do them out? I always say, if you have the wherewithal to be looking at your power meter, you’re probably not going hard enough.


Sebastian Weber  1:37:01

Well, I don’t know. I always looked at my power meter. I have to admit I did those. So you’re not going


Trevor Connor  1:37:05

hard enough.


Sebastian Weber  1:37:08

I had to add a set power output. I don’t know you did what we started doing. I started doing it. And since the late 90s. And we’re doing it actually five to six times per day. We would have half an hour training sounds Wow. Yeah. It looks funny when you are my Orca training camp when you mostly lie on lie at the pool. You know, lay lay at the pool as you know and enjoy the sun and, and so on. And then and then you


Chris Case  1:37:35

why ruin a good vacation with Tabata intervals five times a day?


Sebastian Weber  1:37:40

Yeah, you just got you right for half an hour, just you did like the 10 minutes warm up 10 minutes headed hard. 10 minutes, warm down, rest two and a half hours, six times per day. But more the scientific side, if you say you do it for 10 minutes, and you’re able to reach, let’s say view to max level and the oxygen uptake. You’re able to reach at after let’s say four minutes ish, then you stay at view to max for approximately six minutes. If you do this six times a day, then you have a day in Vegas spend 36 minutes at your view to max and I can’t imagine any hours or work out of the day giving you the same 36 minutes. Yeah, I mean, it sounds


Trevor Connor  1:38:19

amazing. They’re just sounds incredibly painful.


Chris Case  1:38:22

Here’s the most important question I have for you is between the different sessions, were you changing out of your bib shorts? Or were you keeping them on all day long?



randomly, just maybe I’ll change maybe I will. Maybe I’ll wear the shimmy? Maybe I will. I mean, you know, the


Sebastian Weber  1:38:41

time, diamonds a sham is that counts for training time, right? No, but But seriously, the biggest issue here is fueling. Because Because you can’t really have a real meal. Right? Like when you come back, you don’t feel like eating for half an hour. And then if you eat something real then then you don’t feel like doing intervals, right? Or you might lose some weight. doing that. That was most issues that you that you basically only eat, you know, you’re only doing carbohydrate drinks and jails and bars throughout the whole days. And that also sets up your stomach a little bit. So that part was not really nice. Actually.


Chris Case  1:39:18

You said you started doing these in the in the night late 90s? Are these still things that you’re prescribing to athletes that you work with? Or you see people still doing this? Or is this sort of faded? Why


Sebastian Weber  1:39:32

not six times a day, not six times a day but definitely like three to four times on one day, reading it out of distributing it over over a course of four hours writing or something. Doing it three, four times? Yeah, most definitely. I do think


Trevor Connor  1:39:45

it’s important to point out that you work with very high level athletes. You’re working with World Champions Tour athletes, for the average Joe like us at home. Doing this six times in a day.


Chris Case  1:40:00

was thinking about doing it tomorrow actually taking the day off. Saturday, I shouldn’t be calling Christmas.


Sebastian Weber  1:40:07

Tell me tell me if you managed to have breakfast, yes. Because it’s getting brighter.


Chris Case  1:40:14

We’re approaching the longest day of the year. So maybe I’ll hold off for another couple weeks.


Sebastian Weber  1:40:18

Anyway, I feel that you can do it three times on in on one day, this visit as an amateur and recreational athlete I would agree with that I actually


Trevor Connor  1:40:27

used to and I give this some of my athletes a slight variation where I’d have a get up in the morning and go out and do a set of true sprint intervals, which we’ll talk about in a minute. Do that in the morning, then go to work or do whatever I had to do for the day. And then in the afternoon, I would go out and do several sets of tomatoes. And I was really liked that workout. But boy, it was a hard day. Yeah. Okay, so that’s probably a good segue. So we’re talking again about sub one minute intervals. But let’s now talk about true sprint intervals. So kind of that five to 22nd all out sprint. These are fundamentally different from a thought so I’m gonna throw it out there and say 10 seconds recovery is not enough. But let’s let’s talk about it.


Sebastian Weber  1:41:19

Again, try depending on what you try to do, right. But if you look for example, that’s a classic a verb a sprinter will do like a track sprinter or track and field sprinter from athletics. Yeah, you would do whatever one sprint and then don’t move for another 20 minutes. So the don’t move is another stories that don’t move as obviously you don’t want to you know, you want to what you don’t want to expose your system to any kind of endurance effort hurting your like glycolytic system or Vla max or whatever you want to call it that but basically it’s about having you know, full recovery and being able to do a maximum sprint, so to speak all the time and not being compromised like a classical sprint training route traditional approach, you would not want to compromise your your sprint right you would not want to compromise whatever and running straight lines or in cycling your your RPMs or your power output, right you would want to have if you’re going for these maximum Sprint’s you would want again, very traditionally kind of training setup, you will want to reach max power every time. And therefore you need you would need a decent long recovery.


Trevor Connor  1:42:27

And this is for such a big non endurance athlete. So I’m just mentioning that maybe because it’s kind of the one extreme right, it’s so what’s at one end of the scale here, but I remember going to the track and watching the pure sprinters Who are they look more like bodybuilders and cyclists. That’s exactly your scrap they would do a sprint, then they would get off their bike lie in the grass. Yeah.


Sebastian Weber  1:42:51

makes very strange workout, quote unquote, it’s very different from what we’re used to. It’s a short burst of intensity followed by long breaks. And again, the duration is not super long, right? Like you’re barely even restrict sprinters, you barely get something longer than 500 meters. That’s partly depending because of this is what they see in the race in terms of duration. If you look at athletics, then the efforts are even shorter. And you wouldn’t, you would barely see a you know, a 100 meter runner doing vast amounts of 30 seconds effort. That’s just a touch too long already. Right? You would rather see them doing starts or up to 200 meters or something. Because I think what’s important to understand here is that insert in a 32nd effort at the end of the 30 seconds effort approximately two thirds in your your your glycogen faculty energy system already is significantly impaired. So your glycolytic energy supply is already reduced halfway after 20 seconds into an all out sprint quite quite significantly. So obviously if this is the truth is this as a system, you try to hit with a maximum training stimulus. You don’t want to you know come into this range that’s already impaired to him but or a downregulates. Personally Why would I give athletes a true sprint workout the longest holes prescribed is 20 seconds.


Trevor Connor  1:44:23

Often often shorter when they asked me the wattage I basically say you want to try to PR your wattage every single time. Yeah.


Chris Case  1:44:31

Is the last time you did a true sprint interval workout, Trevor.


Trevor Connor  1:44:36



Chris Case  1:44:37

Oh, yeah. Why?


Trevor Connor  1:44:39

Because my sprint is horrible.


Chris Case  1:44:42

I thought you had just given up I thought your answer was going to be something like a 1987


Trevor Connor  1:44:49

though this is the train your weaknesses. It’s just also the sad thing that I do think sprint power is more genetic than training and I do a lot of sprint work and I’ve still rarely ever breakaway And underwater. So let’s get to the recovery like, then let’s move away from that pure track sprinter. And talk about the endurance athlete who’s doing some sprint work, what would be your feeling on a pro both appropriate length for the interval, and then appropriate length and intensity for the recovery?


Sebastian Weber  1:45:20

Right? I mean, again, like, you know, if you want to, if you want to trigger your glycolytic system, you want to increase the, the possibility of your glycolytic system to produce energy, call it increasing Vla Max, then you maybe should not go much longer than 20 seconds, because this is the duration where you can really max out the system. And in terms of Zen recovery, if you let’s say, I mean, that’s relatively simply math, right? If you let’s say, do a sprint for 20 seconds, and your vlm Max is 0.5, then you will be able to reach 10 millimeters above baseline. And so if you want to be sure that you’re recovered from that, in order to do the next maximum effort, that’s the same quality, you need to get rid of, as a marker simplified Spain speaking, you need to get rid of the 10 millimeter electrodes that you accumulate, or at least getting rid of eight or something, right, if it’s a little bit higher, doesn’t really matter. But as a rule of thumb, and then again, if you if you say your, your maximum lactate recovery, or combustion rate is approximately 0.5 millimoles per minute, and getting rid of 10 millimoles, takes 20 minutes, if you’re if you’re fine, just getting rid of AIDS and obviously takes only 60 minutes or something. So that’s a ballpark you want to do here, if you want to do 20 seconds, all out sprints, and maximize the use of your glycolytic system. The difference with a track sprinter is that you would not sit in the grass and wait you would actually keep pedaling at depending on where your maximum recovery at is 60 70% of threshold, maybe 50% 75 depends on your profile and use this. And you can therefore easily included into your base training or endurance training, whatever kind of other endurance kind of training, right. So that could be there could be one way how you want to do this in terms of increasing your, your sprint power. And this would be for that glycolytic system, a pretty simple or precise way to approach that. Right as so to speak, as kind of let’s call it a standard kind of interval setting here. And you would not need to care about your creatine phosphate as much right? Because in this scenario, that’s not what you’re mainly interested in right talking about increasing glycolytic energy supply.


Trevor Connor  1:47:41

So I take it, it’s like you said, If you really want to do this, right, go sit in the grass for 20 minutes, I always try to balance that with most of my athletes have a life and only so much time. So I my balance is I’ll tell the athletes go out do that 10 to 22nd, Sprint, and then I basically don’t want them pedaling for three, four minutes. mm and then do the next sprint. It’s not perfect, but it’s just it’s that balance between what’s optimal and not having to spend five hours out in the bike. Yeah,


Sebastian Weber  1:48:16

yeah. But then also, they’re all different kinds of other, you know, Sprint trainings out there, so to speak, right, which also target more like the neuromuscular side of things, and not so much maybe the energetic or metabolic side of things, right? Especially when it comes to sprint performance should not be forgotten that they’re there and other and other layers to performance to it. Right. And then you will want to also look at the leg speed. So the RPMs at the cadence and look at these things to design a more complete sprint workout. I love the seated five to 10 seconds sprint at super high cadence to really work that neuromuscular side, right? And what do you choose for the rest of that,


Trevor Connor  1:48:59

since that’s more neural muscular, and I’m not looking for super high wattage is, I will often give that to my athletes in the as we’re getting towards the end of the winter to work that leg speed to work the neuromuscular side or in the winter and tell them to do it on an easy ride and just say, you know, do them every 510 minutes. You don’t have to be precise and just ride really easy in between. Right. Well, cool. Very good demo. We agreed on that, too.


Chris Case  1:49:27

Yeah, it sounds like it.


Sebastian Weber  1:49:29

Well, I mean, yeah, I mean, yeah.



Maybe not.



Here we go.


Sebastian Weber  1:49:36

I mean, I mean, it’s not agreeing. It’s basically I use this VISTA lines of Greipel and so on. I use different intervals where there’s a duration was much much shorter, but then the power output was not maximum as well. And we had we had a lot of success with that actually thinking about doing a webinar about sprinting, Sprint training that we successfully used in the past so maybe have to put some time aside to do that, yes. So we had different donor over the years working working with this, this guy’s back him and Peter and so on, it’s like, try different kind of have seen and try different kind of offspring training, which sometimes do is much, much shorter recovery. But then again, in order to fulfill that, and in order to have a good quality, which again, for me is important for talking about neuromuscular adaptation, the power output would not be maximum, but it would be more like a control thing. And then especially with sprinting, when we design an interval training program, or sprint training program, I think, especially as printing we need to talk about, if you do is it seated, or out of the saddle, or if you allows it to be mixed. Because like, obviously, in a five minute effort, only a relatively small amount will be out of the saddle, if you allow for it for me, you should not but if you allow for that there’s a sprint of 10 1520 seconds, you know, the majority of the duration of of the effort can be can be done out of the settlement. And depending on what you want to use it for, and what you ideas why you’re doing this, I shouldn’t be you should be precise and strict on how we prescribe those seated out of the seven,


Trevor Connor  1:51:18

I agree completely. And when it the focus is neuromuscular, that’s part of why I tell my athletes it’s not about trying to hit your peak power because a watch my athletes sit there going moving their body all over the bike, the form is awful and you go that’s bad neuromuscular training. So when I give them those Sprint’s it’s seated, and it’s as hard as you can go while maintaining good form, because that’s what you’re trying to train.


Chris Case  1:51:44

Right? It does sound like we’ll have to have you back on the show Sebastian to do a whole episode on how to improve your Sprint’s both from a training point of view from a neuromuscular point of view from a technique point of view, because you’ve worked with some great sprinters and you have some knowledge here that Trevor probably doesn’t have because he can’t break.


Trevor Connor  1:52:04

This is where we’re gonna get into having a video component to the show via we’re just gonna video me sprinting Yep. Caption. Here’s what not to do. Here’s how let’s talk about the right way to do


Chris Case  1:52:14

  1. Exactly.


Sebastian Weber  1:52:16

could be it could be interesting case study to try to improve.


Chris Case  1:52:19

It could. That could be great.


Trevor Connor  1:52:21

I have tried a whole bunch of things I have actually once in my life, won a sprint. But it’s because I went else was possibly the only person on the planet with a worse sprint than me.



Are you going to name this person? No. Okay.


Trevor Connor  1:52:37

He would not appreciate it. Yeah. All right. And it was the biggest GIMP sprint you’ve ever seen in your life?


Sebastian Weber  1:52:44

Well, I mean, again, like, Look, we could try right, you could make like a nice case study. I don’t think we should. Maybe it will not work. But I think it would be fun for Chris and me at least Yeah, absolutely.



sit there and laugh. Yeah. And if


Chris Case  1:52:55

we can somehow make this happen on my Orca with all of us there, that’d be even better. We have to do a,


Trevor Connor  1:53:01

my or no, my sprint. I like this. Yeah. All right. Let’s do this. I will embarrass the heck out of myself. Good. Good. That’s what we need.


Chris Case  1:53:11

Well, Sebastian, you’ve been on the show. It’s been a while. But you know, that we like to close out with take home messages, most important things that we want people to take from the episode. Are we ready to go there? And are you ready? Are you ready to give us your your final message here.


Sebastian Weber  1:53:29

So for me, I think the most important message here is that people often think that defining a duration and defining an intensity of interval training defines what kind of stimulus it is in terms of training or adaptation, what often is forgotten, or basically unknown measurements are known, because it’s often not even prescribed, is choosing the right intensity and the right duration for the recovery. Because this will change a lot what’s going on metabolic D, what’s going on physiologically, doing these intervals. And therefore, it’s important to remember that just because you’re repeating the same power output, doesn’t mean that you’re repeating the same metabolic stimulus. This will, in most cases, change tremendously from the first interval to the next to the next to the next to the last. And that’s something to take into account and really think about it and really set up a training program that will prescribe intensity and duration for recovery.


Trevor Connor  1:54:32

I’m just going to add a little bit to that, because and look, Sebastian, we sent him the outline and he emailed us and rightfully said, Trevor, you left a few things out. So basically, my one minute is actually a one minute that’s fashion sent to me. So this is actually Sebastian’s two minutes. second minute, but it’s expanding on that. What I’m going to say is there’s a lot of prescriptions out there that look really cool on paper, like do a one to one. So whatever line through your interval is the recovery should be the same length and they look cool on paper. But what’s the physiology behind that? And I think the best way to approach that rest is to say, what physiological effect Am I looking for? Am I trying to recharge my phosphocreatine? Am I not? Am I trying to let my lactate levels come back down? Or not? You need to look at what’s the best physiological effect, and then choose the recovery length and intensity appropriately. Mm hmm.


Chris Case  1:55:36

Chris? Well, yeah, you know, I think that when you first suggested we do an episode on rest periods, I was like, a lot of people out there and I thought, well, that doesn’t sound all that interesting. But I think that this was one of this was a very compelling conversation that touches upon the importance of this topic that is just neglected or ignored or forgotten about by so many people. So I, I do hope that people listen to the entire episode. I think there’s so much to take from this episode. That’s that’s my take home is that this is in reiterating what you guys have already said, which is, this is a very critical part of training, but a lot of people don’t think too much about it.


Chris Case  1:56:30

That was another episode of bass talk. As always, we love your feedback. Email us at Fast Talk at Fast Talk Labs comm or record a voice memo on phone and send it our way. Subscribe to Fast Talk. Wherever you prefer to find your favorite podcasts. Check out the Fast Talk Labs newsletter by visiting www dot Fast Talk and signing up there. The thoughts and opinions expressed on Fast Talk are those of the individual for Sebastian Webber, Ruth Linder, Steven Chung, Jerry Berg and Coach Trevor Connor. I’m Chris case. Thanks for listening.