Zones Are a Range, and Not a Specific Number, Featuring an All-Star Cast of Guests

In this episode we look at the big picture when it comes to training in zones, or ranges, versus training a target number. Because what number is best?

Fast Talk Podcast Q&A
Photo: Simon Connellan

We’re incredibly lucky here at Fast Talk Labs to be able to talk with some of the most intelligent physiologists, coaches, and athletes about training, and sport science generally, on a weekly basis. We glean so much insightful information just by having access to them on a regular basis. Through Coach Connor’s countless hours of dedicated research to keep up on the latest science, we’re then able to synthesize all of this information into what we hope are digestible conversations, helping you to better understand the science that propels cycling performance. Occasionally, we like to step back and summarize the things we’ve learned, often prompted by the many questions we receive from our dedicated listeners. Today is just such an occasion. The last time we did this type of show was Episode 68: The Big Picture—The Three Types of Rides You Should Do. Today, we look at the big picture when it comes to training in zones, or ranges, versus training a target number. Because what number is best? We talk about training zones constantly. If your zone 2 is 160 to 190 watts, for example, then is training at 190 watts better than training at 170 watts? Is going harder always better? Stay tuned for those answers. Next, we’ll address four fundamental principles of human physiology that relate to training in ranges: specifically aerobic and anaerobic thresholds, fat burning capacity, and maximal lactate clearance—all in an effort to maximize your training experience. Finally, we take an opportunity to remind everyone that humans aren’t machines. Perhaps that’s stating the obvious, but sometimes it’s good to remind ourselves that we are all individuals and have different needs, and goals for our riding. Today we hear from a vast array of former Fast Talk guests, including:

  • Colby Pearce, an incredible time trialist, coach, and bike fitting expert
  • Dr. Stephen Seiler, one of the world’s leading sports physiologists
  • Sepp Kuss, pro cyclist with Jumbo-Visma
  • Toms Skujins, pro cyclist with Trek-Segafredo
  • Dr. Andy Coggan and Dr. Stephen McGregor, leading exercise physiologists
  • Hunter Allen, leading cycling coach
  • Sebastian Weber, lead scientist at INSCYD and elite cycling coach

Let’s make you fast!

  1. Deley, G., Millet, G. Y., Borrani, F., Lattier, G., & Brondel, L. (2006). Effects of two types of fatigue on the VO(2) slow component. Int J Sports Med, 27(6), 475-482. doi: 10.1055/s-2005-865837 
  2. Dudley, G. A., Abraham, W. M., & Terjung, R. L. (1982). Influence of exercise intensity and duration on biochemical adaptations in skeletal muscle. J Appl Physiol Respir Environ Exerc Physiol, 53(4), 844-850. doi: 10.1152/jappl.1982.53.4.844 
  3. Faude, O., Kindermann, W., & Meyer, T. (2009). Lactate threshold concepts: how valid are they? Sports Med, 39(6), 469-490. doi: 10.2165/00007256-200939060-00003 
  4. Keir, D. A., Fontana, F. Y., Robertson, T. C., Murias, J. M., Paterson, D. H., Kowalchuk, J. M., et al. (2015). Exercise Intensity Thresholds: Identifying the Boundaries of Sustainable Performance. Med Sci Sports Exerc, 47(9), 1932-1940. doi: 10.1249/MSS.0000000000000613 
  5. Laursen, P. B. (2010). Training for intense exercise performance: high-intensity or high-volume training? Scand J Med Sci Sports, 20 Suppl 2, 1-10. doi: 10.1111/j.1600-0838.2010.01184.x 
  6. Messonnier, L. A., Emhoff, C.-A. W., Fattor, J. A., Horning, M. A., Carlson, T. J., & Brooks, G. A. (2013). Lactate kinetics at the lactate threshold in trained and untrained men. Journal of Applied Physiology, 114(11), 1593-1602. doi: 10.1152/japplphysiol.00043.2013 
  7. Serrano, E., Venegas, C., Escames, G., Sanchez-Munoz, C., Zabala, M., Puertas, A., et al. (2010). Antioxidant defence and inflammatory response in professional road cyclists during a 4-day competition. J Sports Sci, 28(10), 1047-1056. doi: 10.1080/02640414.2010.484067 
  8. Urhausen, A., Weiler, B., Coen, B., & Kindermann, W. (1994). Plasma catecholamines during endurance exercise of different intensities as related to the individual anaerobic threshold. Eur J Appl Physiol Occup Physiol, 69(1), 16-20.  

Episode Transcript

Intro  00:00

Welcome to Fast Talk, the Velonews podcast and everything you need to know to ride like a pro.


Chris Case  00:10

Hello and welcome to Fast Talk Episode 101. I’m your host Chris Case. We’re incredibly lucky here at Fast Labs to be able to talk with some of the most intelligent physiologists, coaches athletes about training in sports science generally, on a weekly basis. We glean so much insightful information just by having access to them on a regular basis. Through Coach Connors countless hours of dedicated research. To keep up on the latest science, we’re then able to synthesize all this information into what we hope are digestible conversations, helping you to better understand the science that propels cycling performance. Occasionally, we like to step back and summarize the things we’ve learned, often prompted by the many questions we received from our dedicated listeners. And today is just such an occasion. The last time we did this type of show was Episode 68, the big picture and the three types of rides you should do. Today we look at the big picture when it comes to training in zones or ranges versus training a target number, because what number is best? We talked about training zones constantly. If your zone two is 160 to 190 watts, then it’s training at 190 watts better than 170 watts? Is going harder better? Stay tuned for those answers. Next, we’ll address four fundamental principles of human physiology that relate to training in ranges, specifically aerobic and anaerobic threshold, fat burning capacity, and maximal lactate clearance. all in an effort to maximize your training experience. Finally, we take an opportunity to remind everyone that humans aren’t machines. Perhaps that stating the obvious, but sometimes it’s good to remind ourselves that we are all individuals and we have different needs and goals for our riding. Today we hear from a vast array of former fast talk guests including Colby Pierce, an incredible time trialist coach and bike fitting expert and soon to be podcast host, Dr. Stephen Siler, one of our favorites and one of the world’s leading sports physiologists, Sepp Kuss pro cyclists with Jumbo Visma. Tom Skujins pro cyclists with Trek–Segafredo, Dr. Andy Coggan and Dr. Steven McGregor leading exercise physiologist, Hunter Allen, a leading cycling coach, and Sebastian Weber, lead scientist at Inside, and an elite cycling coach in his own right. Home, home on the range, because we’re talking about ranges. Anyways, I’m the Lone Ranger. Let’s make you fast.


Trevor Connor  02:46

Good morning, Chris. How you doing?


Chris Case  02:48

I’m good.


Trevor Connor  02:48

We’re now officially in the 100’s.


Chris Case  02:50

We are. We are


Trevor Connor  02:51

I had to go and change all our templates, because we named them all FT and then the number and it’s a pain to always type the one now. So in other ft one, and then yeah add on.


Chris Case  03:01

Excellent. Efficiencies.


Trevor Connor  03:03

A big moment. I got to change a template. I’m excited.


Chris Case  03:07

Nice. I know you love your templates.


Trevor Connor  03:09

Yes, I do.


Should you Train at a Specific Number? Or Should you Train in Ranges?

Chris Case  03:11

So today we are taking a step back to look at a big picture topic. We’ve received a lot of emails and questions about this particular subject. And it comes down to should I train at a specific number, or should I be training within ranges? And a lot of people have written in saying, you know, I, m- my zone two is range ranges between, say 160 and 190. Doesn’t that mean I should be training right at 190? Well, we’re asking that question. Or the other question is, should you sometimes train at 190? Sometimes train at 170. These ranges are ranges for a reason. And that’s what we want to get into today.


Trevor Connor  04:00

So we are getting into the hole is harder, always better concept. So yes, people are getting their zones, you need to stay in your zones. But if, as you said your zone is 160 to 190 isn’t 190 better than 170? Because it’s harder. Particularly because we live in the era of tracking your training stress, and one night doing a couple hours at 190. You generate more training stress than doing a couple hours of 170.


Chris Case  04:31

People like those big numbers, bigger the number, the better. You’ve done that week, right? Sometimes that isn’t necessarily the case.


Trevor Connor  04:37

No, it’s not always necessarily the case. But it’s when we do these summary episodes, we kind of watch what’s the trend and the questions that we get. And for some reason this is what would you say we got four or five, six emails right in a row asking, asking this very question of here’s my zone, shouldn’t I be sitting right at the very top end of that zone? So, look, there are times where that’s completely appropriate. But we want to discuss why that’s not always best and why. So I don’t actually call them zones. When I work with my athletes, I call them ranges. And it’s a range for a reason. When my athletes asked what part of that range that I work in I, my answer is always anywhere.


Chris Case  05:16

Mm hmm.


Trevor Connor  05:24

It’s, it’s a range for a reason to me, you are. So I think of his training energy systems. And within that range, you are training that particular yep. Take a step back. This is one of those all else being equal. So we design a ride, it’s a certain length, volume, everything plays in. But once you’ve designed the rest of the ride, how long it’s going to be what’s the particular work you’re going to do, you’re given a particular range. And to me, as long as you’re doing the same work anywhere in that range is fine. And I will usually tell my athletes, you know, what, target the middle. Don’t always target the edges. And that’s a lot of what the show’s gonna be about today is why actually targeting the edges, is some time is not always going to get you to where you want to be,


Chris Case  06:17

I can understand the temptation to see a range and say, okay, I’m just going to basically simplify this, and stick to a single number, because that simplifies things, perhaps it makes it easier when you’re out on the ride to remember that number. Perhaps when you’re cross side, if you’re doing a intervals or something, it’s just, that’s my number. So I do get that temptation. But what we’re trying to explain is that with a little bit more thought, you can get more out of your training. And also, if sometimes you have to think about a number and not a range, then maybe the more appropriate number you focus on is in the middle and not at the edge.


Trevor Connor  07:01

Right. And I just want to emphasize this because we won’t go back to this for the rest of the show. But this is all else being equal. So remember that if you’re training in your zone two, range 30 minute ride is a recovery ride, a six hour ride in your zone, two ranges, a good hard endurance ride.


Chris Case  07:20



Trevor Connor  07:20

So when we’re talking about the ranges, and why you want to target the middle, why, you know, within the range, it’s we’re saying it’s all the same. That’s after everything else has been designed.


Chris Case  07:33

Mm hmm.


Trevor Connor  07:34

So we’re not going to talk about the impacts of volume and interval work and all that sort of stuff. We’re just talking. Once the ride has been designed, where’s the best place to be in the zone?


Chris Case  07:43



What Zones Are and Aren’t About

Trevor Connor  07:46

Before we dive into why we feel it’s important to look at the whole range, and not just a target or specific number, let’s share a clip from Episode 72. Where we talked with in many ways, the originators of power zones, or levels as they prefer to call them. Dr. Andy Coggan, Hunter Allen, and Dr. Steven McGregor. They share their thoughts on what zones are and aren’t about.


Dr. Andy Coggan  08:11

But anyone who thinks that there’s magic and training at a particular intensity, you know, just doesn’t understand well, first, they don’t understand how the body responds to exercise, but they also don’t understand what you know, Hunter and I and then with Steve, join in, I’ve been trying to educate people about for the past two decades. Again, I come back to they’re called levels and not zones for a reason, have always been called levels. And I, I’ve railed against this, you know, if you’re not as been around as long as I have, you may not remember the era in which people were discouraged from going too hard in the offseason, because they will you’ll blow up their capillaries. You go out and you go. Yeah, snicker snicker, I hear you Steve. Then you go out and ride with Adam, it’s like, no, I have to, you know, get off my bike and walk up this hill, because I’ll blow up my capillaries. You know, that’s ridiculous. That’s not how people ride bikes in the real world. So if you overly constrained somebody’s power out, but because of the way you’re prescribing training, all you’re doing is making the training less specific. Go back to the original system that I put out there back in 2001 now. It refers to the average power either for the interval if you’re talking about interval type work, or refers to the average power for the entire workout if you were talking about, you know, just a steady state endurance ride, or if it’s something like a tempo session, well, you know, you warm up and you cool down but you focus on what was the average power over the hour and a half in the middle. But that doesn’t mean that power remains within that range at all times. In fact, you know, exactly what you really should be aiming for because we don’t go out in time trial everywhere. At least not masterwork.


Hunter Allen  10:00

And this actually goes back to what you were talking about with regard to the reasons for zones, and, you know, kind of the problem with zones is I, you know, Andy kind of cited a popular notion from back in the day, which seems like only yesterday, but which actually was, you know, 15 years ago, blown capillaries. But also, I can think back farther than that, and which is kind of still been around for a while is the notion of no man’s land. Right, that was a particular zone to stay away from. So there’s zones you target in zones you want to stay away from. And actually, in actuality, most of what a lot of people would consider no man’s land is actually the place that a lot of us spend, or racers spend a fair bit of time actually riding their bike. So it’s a zone, or it’s a, an effort level that you actually have to be in at some point, whether it’s in training to race effectively, or racing effectively, right. Avoiding it, like the plague like it’s going to cause some type of undue damage is, is really a misguided notion. And, and so the other aspect of, again, quote, unquote, levels or zones is that they give a standardization a framework for people, because in the case of the book, when it first came out, without that framework, it’s really difficult to describe things to people on a generally applicable basis, we can say generic basis, but as a generic is generally applicable.


Trevor Connor  11:23

I like the fact that in your eye levels, you said it’s it’s not like you suddenly go from 292 to 291. And you’re training different energy systems, that it’s a continuum.


Dr. Steven McGregor  11:34

Right? Yeah, it comes back to it’s a continuum. What is the magic number of subdivisions that is not too many as to be unwieldly? But is enough to at least try and pay lip service to the actual complexity? It, my original answer was seven.


Hunter Allen  11:53

And I think that gets one when the, when the inventor of the levels doesn’t even know how many levels they are, I think that kind of attributes and the level of the magnitude of importance, he subscribes to the actual levels themselves. Again, it’s, it’s a practical convention to convey notions that are more standardized. But everything happens on a continuum. And whether it’s nine or 15, or three, is just a practical consideration more than anything else? And yeah, it’s getting to be a lot, isn’t it?


Dr. Andy Coggan  12:24

Yeah I hear you. Again, back to that back to my original point, no, why do we have these things because it really gives clarity, it helps us as coaches, and also as athletes to, you know, again, quantify when we’re there, when we’re in the right area of training to train that specific system.


Trevor Connor’s Brief Overview on Energy Systems

Trevor Connor  12:44

Let’s get back to talking about energy systems.


Chris Case  12:47

So let’s talk a little bit more about those energy systems that you spoke of. That’s the way you like to think about this when you’re designing a plan. And when you’re training yourself, it’s all about the energy system. So maybe give us a brief overview of what you mean by that.


Trevor Connor  13:03

I just like that term. The truth being if I ever sat down and made a list of what all the energy systems are, you would very quickly look at that and go well, that’s actually point to some things go Yeah, that’s definitely an energy system, you’d point to other things ago, that’s not actually an energy system. That’s a different type of adaptation. And I would say you’re fully right. I just don’t like to say to my athletes, energy systems,  plus fuel metabolism, plus muscle fiber adaptation, plus, you know, give the proper sentence to fully explain it. So it’s just kind of nice to say, let’s talk in terms of energy system.


Chris Case  13:38

Right, and these things are fluid?


Trevor Connor  13:40

Yes, it is all very fluid. And my bias comes from the fact that technically, my master’s, my major was bioenergetics.


Chris Case  13:49

Mm hmm.


Trevor Connor  13:49

I basically spent my whole master’s studying how we generate energy energy systems. So there is a bias here, and I get it, you’re going to listen to this and go, wait a minute, that’s not an energy system. You’re right, we’re just using a term somewhat inappropriately.


Chris Case  14:04

Mm hmm.


Trevor Connor  14:05

Most of the time appropriately. The key thing to remember when we’re talking about these energy systems is well, we like to think harder is better. Often with an energy system, it’s getting trained just as well, anywhere within that zone. And as a matter of fact, there are cases and we’re going to go through a couple of examples, where if you get too hard, you’re not benefiting that energy system as much. So one of the things we’re going to talk about is maximal lactate clearance, you would think, oh boy, that happens right at your anaerobic threshold, not actually the case, your your optimal point for for lactate clearance is about 95% of lactate threshold, and it starts to decline once you get to lactate threshold. So there’s a case of where harder is not better.


Chris Case  14:56

And I remember having this discussion when we devise my training plan for the hour record. And we did a lot of this type of work and it was always, here’s the number. Let’s take a percentage of that and work just below that.


Trevor Connor  15:12



Chris Case  15:13

And and we had Neil Henderson confirm that. That was the type of training that Rohan Dennis was doing when he was preparing for the hour record. So this is the type of stuff that-that a lot of people are using for those hour long efforts or those time trial specific training efforts out on the road.


Trevor Connor  15:33

Mm hmm.


Trevor Connor  15:33

Remeber, we had Sebastian Weber on the show, and he talked about this when you’re trying to train that VLA max when he was talking about training time trialist. He said he has them do a lot of big gear work.


Trevor Connor  15:44

Just below that anaerobic threshold, and maybe we throw that clip in right here.


Sebastian Weber’s Advice on Trying to Train your VLA Max

Sebastian Weber  15:49

You need to trigger those a little bit more fast twitch fibers so to speak, and they have a higher recruitments threshold. So you can’t only go easy right? We tried that about almost 15 years back right? I developed a test to measure VLA max using ergometer test, we use muscle biopsies to validate this test. And then we trained athletes, because the questions come up. Okay, how do we train that? And the first idea was just go easy, right, just don’t touch your glycolysis. The problem is now you’re not recruiting the muscle fibers which are responsible for VLA max. So long story short, your intensity needs to be a little bit higher more towards what you might call sweet spot or sub threshold or something. And then you need to stay there for some good amount of time repetitively or continuously. That’s that’s what’s important, too is intensity can’t be too low, should be a little bit sub threshold. You know, you can you can do some things like lowering the cadence, like which increases the talk, which then again recruits more FT fibers, if you are a sub threshold,


Trevor Connor  16:53

Now you’re saying sub threshold sweetspot? Are you saying pretty significantly below or just below threshold?


Sebastian Weber  16:59

Well, that depends on how much time you can invest? Right? If you’re going for a six hour ride every half an hour, you want to ride sub threshold for 30 minutes, and you have to be more below threshold, right? And if you’re only doing this for two hours, then maybe 90% of threshold is okay, if you want to do this for five hours, and you maybe need to go at 80 or 75% threshold. Right? So depends obviously, for how long you can do this at how often are you doing this.


Trevor Connor  17:27

So remember, we we had Dr. Indigo San Milan on the show a while back. And he was talking a lot about this about that recruiting those fast twitch 2V fibers to work more robustly and he was big on training right at a aerobic threshold, or VT one or the other. There’s a variety of different names for it. But right at that point where lactate starts to rise up, so around kind of 1.7 to two millimoles on a lactate curve. And he was big fan of just riding there for four or five hours if you can do it. Because that’s really going to get those fast twitch muscle fibers working aerobicly. So your sounds like you’re saying if you have the time, that’s a great way to do it. If you don’t have the time, then then higher intensity closer to threshold. Lower cadence can be really beneficial. Am I hearing you? Right?


Sebastian Weber  18:18

Umm, not entirely first, like first increase of lactate. That’s very tough. Because you do the statement, you immediately bond yourself to, to to a certain testing protocol.


Trevor Connor  18:34

Which is fair.


Sebastian Weber  18:35

Like this power output which left which is the power but if it’s selected increases is tremendously different if you do one minute increments or 10 minute increments.


Trevor Connor  18:45

No, that’s fair and to that credit, when we had a Indigo on here, part of what we were talking about was that his testing protocol, and he uses a 10 minute testing protocol because he is huge on the aerobic side.


Sebastian Weber  18:56

Okay. But anyway, so assuming, for me is this sounds like the sounds like a quite low intensity. And as I as I indicated, we’ve done that and we’ve done that looking and doing muscle biopsies, and we’ve done that looking at adaptations in single muscle fibers. And for some people it works, but if you have a reasonably high amount of source Ft fibers, then it maybe doesn’t really work. And one part of the mechanism is that you can stay lower with an intensity because all of the time like you said you brought up something like five hours you FT fibers fatigue and then you would also recruit more ft fibers. But that then you are back to you know being the need to really ride those five hours and I doubt that this is really applicable for most of your listeners out there. So so again for for what we did, there was a couple of amateur athletes over 30 looking at specific adaptation in single muscle fibers. If you go to low intensity, you have a fair chance that it’s not working for a big part of your group. If you go a little bit higher intensities, and you have a very good chance that it almost works for everybody. And therefore, I would say, if you really want to lower VLA max don’t stay too low. And we’ve seen it also like from a lot of users of the insights of fans of past months, seems to be like a common misunderstanding. People still have, like saying, oh, yeah, I don’t want to decrease the VLA max adjust right easy. And then they are surprised at four months later VLA max maybe even increased.


Trevor Connor  20:37

Let’s get back to the show.


Getting More Specific with Energy Systems

Chris Case  20:39

Let’s be even more specific, what are some of the energy systems you’re talking about here?


Trevor Connor  20:45

So we’ve discussed this before there, there are many, but I’m really going to focus on four here. Part of the reason I want to focus on these four is there’s a lot of different zone models out there. There’s simple ones like the Dr. Seiler has a three zone model, I’ve seen zone systems that have nine different zones. When you actually look at our physiology, there’s only a few key break points. So a lot of these zones are just based on the zone models are based maybe on experience, maybe on what athletes do.


Chris Case  21:17

Mm hmm.


Trevor Connor  21:17

But you can’t point to something physiological and say, there was a change there,  something was going on there.


Trevor Connor  21:23



Trevor Connor  21:23

So when you’re talking about if you did a lactate test, or a ramp test, and we were looking at what was going on physiologically, here’s the the key breakpoints. Obviously, there’s the two thresholds, there is your aerobic threshold, and there’s your anaerobic threshold. Aerobic threshold is that point where if you are on a doing a lactate test, you start seeing that rise in lactate. So proper lactate test, you would have a few stages where your your lactate is going to stay low, depending on your level somewhere around 1, 1.2, you’re not going to see lactate rise at all. Aerobic threshold is after you start to see that rise. So there is a physiological a clear physiological change that is happening. And there’s a lot of explanations again, this is we don’t want to go too deep into the weeds. We’ve done episodes on this, this is kind of the summary. But one of the beliefs. I believe in this, one of the things that’s happening when you hit that aerobic threshold is now you’re starting to recruit those 2A fibers.


Chris Case  22:31

Mm hmm.


Trevor Connor  22:32

So you’re you’re, you’re starting to bring in fast twitch muscle fibers. Another thing so literally in our last episode, when we were talking about Dr. Seiler, he brought up the fact that when you are below your aerobic threshold, going out and doing a long ride, you’re not going to see any sort of cardiac drift, and I’ll do the quick explain because we brought up cardiac drift a ton. That’s basically if you’re riding at a steady wattage. If you’re experiencing cardiac drift, you would see a rise in your heart rate. So below aerobic threshold, you’re not going to see that whatever your your heart rate is at a given wattage is going to be pretty much the same at the start of the ride and the end of the ride. Assuming you’re properly hydrating. It’s not insanely hot outside and other factors. Above aerobic threshold, you’re gonna start seeing cardiac drift. Obviously, the other key breakpoint is that anaerobic threshold. And again, a while ago, we had a whole episode talking about thresholds and all the different terms for it. Mm hmm. There are many. I personally really like MLSS, maximal lactate steady state, because again, it’s looking for a physiological breakpoint, something where something physiologically changes. And MLSS, as the name says is the point where you can no longer maintain homeostasis, you might be able to go for a certain length of time, but it’s going to take a toll on you, you’re going to see a lot of changes and you can’t sustain it.


Chris Case  24:06

Mm hmm.


Trevor Connor  24:07

So MLSS below that, even though it can be hard, it’s considered sustainable for an extended period of time. It’s also the point where you start really relying on anaerobic metabolism. So you, you it’s not like all of a sudden you’re now using anaerobic metabolism below MLSS below anaerobic threshold, you’re starting to bring in some anaerobic metabolism. But now there’s just that point where you’re starting to really bring in those two X fibers that really don’t do a lot of work aerobically. You’re now generate a lot of anaerobic energy. And like I said, you are on a very short fuse at this point.


Chris Case  24:44

Yeah, that’s, I think that paints the picture of these being fluid and also overlapping.


Trevor Connor  24:51



Chris Case  24:51

That’s key to understanding all of this is that these things are not black and white, a division between one and the other. They’re there they overlap. And you can be hitting multiple things at the same time. And you are often doing that, if not always doing that.


Lactate, Aerobic, and Anaerobic Thresholds

Trevor Connor  25:10

This is because is really fun, interesting contradiction that we’ve gotten questions about because people get a little confused by this. And there’s actually a review article that I really liked called lactate threshold concepts, how valid are they? And most of what I was just explaining is summarized in this review, another one called exercise intensity thresholds, identifying the boundaries of sustainable performance by Dr. Keer. Those would be the two that I would say, kind of explain a lot of this explained this interesting contradiction where like you said, on the one hand, it’s very fluid. And we mentioned this in the previous episode, when physiologist talked about lactate threshold, they’re talking about that entire range between that aerobic threshold, and that anaerobic threshold or MLSS. Because as we said, aerobic threshold is the point where you start to see the rise in lactate, hence you’ve now hit a lactate threshold. Yet, there are still these these key breakpoints where they go even though this whole thing is fluid, there’s these two points where it’s clear below this


Chris Case  26:21



Trevor Connor  26:22

-one things going on. Above this, another thing is going on.


Chris Case  26:25



Trevor Connor  26:26

And they have an impact. The last thing to bring up about that anaerobic threshold that’s been mentioned multiple times in many studies, Dr.- and sorry, as usual, we’ll put up a bunch of references on the website for people to check out. Dr. Seiler wrote a little bit about this. But above that anaerobic threshold above that MLSS, there is a disproportionate increase in sympathetic nervous system activity. So I could go deep into the weeds in this but basically what all these these studies say, and in particular, the one I would recommend is one called an older one, plasma catecholamines during endurance exercise of different intensities, as related to the individual anaerobic threshold, how’s that for name, and that was in the European Journal of Applied physiology back in 1994. But the gist of it is, there is a toll that you take when you go above anaerobic threshold. There are certainly some sympathetic stress when you’re between those two thresholds. But to get above that anaerobic threshold and all of a sudden, you’re really hitting the system, there is going to be a price to pay that you don’t pay below. Hence, the reason we’ve often said you got to be careful about that work above anaerobic threshold, you just can’t do it every day, because cuz of this sympathetic stress, because of the the sort of damage it’s doing to your system, and the increased need for recovery after the sort of work.


Chris Case  28:02

Again, those references will be up on the website, for this episode.


Two Important Physiological Things to Point Out

Trevor Connor  28:13

Now, here’s two other good physiological things to point out. One of these, as we mentioned earlier, and it has confused a lot of our listeners in the past, it is confusing. So we’ve gotten a lot of questions about this. But while we talk about that anaerobic threshold, and there’s key things that happen there, and it’s often also referred to as you know, a lot of people when they think about lactate threshold, that’s what they’re thinking about. That higher what were the a time trial. But as we said, there is a point where your body is optimally clearing lactate, so that whole system is revved up at its highest. That is not at your anaerobic threshold.


Chris Case  28:55

Mm hmm.


Trevor Connor  28:56

That is a little below right around 95%. And we’ve had Sebastian Weber say this on the show, we’ve had Rob Pickle, say this on the show, who was a physiologist who worked at BCH for years with Dr. Pruitt, and many of them have said if you’re really trying to train that light, if you’re a time trial list if you’re a breakaway rider and you’re trying to train that ability to sit right around your threshold and go hard for long periods of time. Actually training at this just below point is optimal. Tom Skujins a rider with Trek Segafredo and somebody who’s worn the polka dot jersey at the Tour de France. Talk to us about his training and why he doesn’t apply a “harder is better” approach. Some of it does come down to what we were just talking about not building up too much sympathetic stress.


Tom Skujins Explains his Unique Training Approach

Toms Skujins  29:51

Depends on the type of interval just because the sustained efforts, the long ones that you keep on going forever. It’s very important to keep an eye on that number and not go over just because as soon as you go over your body turns to a different kind of intensity and builds lactic acid, and you won’t be able to sustain it. Whereas if you have shorter intervals, which are like two minutes, five minutes, then it’s not necessarily about the actual power number. But it is in that regard. As soon as you go for too far down, it’s not worth doing it. But sometimes it’s the higher you go, the better. Where- but at the same time, not for me, I never, I’m almost never going flat out in training, just because I like to keep my race legs for the races. But and just doing those intervals at a specific power number, like saves your legs a little bit and doesn’t let you go too far into the red.


What Training at 95% Really Does to Your Body

Chris Case  31:02

So maybe it’s worth asking the question, what’s the mechanism by which training at 95% slowly pushes up that threshold so that you can increase it or does it not push it up, it just helps your body’s ability to clear?


Trevor Connor  31:18

So again, I don’t want to go too deep into the weeds. Because it’s not lactate that shuts you down. Mm hmm. Now, there’s that old concept that we produce lactic acid. And that’s been disproved, we don’t produce lactic acid. We did a whole episode on that for anybody who who gets upset by my saying that but no, lactic acid can’t exist in the human body and physiological quantities, we do produce lactate, and we simultaneously shunted out of ourselves with acid, hence, you see that decrease in pH. Well, you are also seeing an increase in lactate. So because our bodies are aware of that they have sensors. So even though it’s not the lactate that’s shutting you down, your body does sense the increase in lactate, it does sense the increase in or decrease in ph. And at certain point says this is going to damage you. So I’m going to put the brakes on and make you slow down. So the more you can train that ability to clear the lactate, the less of a response, your body’s basically going to say, okay, don’t have to set off the alarm bells yet. And I’m going to let you go a little bit harder, I’m gonna let you go at this intensity a little bit longer. So training that clearance correlation between your body’s ability to kill their lactate, and your body’s ability to manage that acid buildup. Because one of the things that your body does to deal with the lactate is other tissues can take it up. So when you’re using anaerobic fibers, they’re pumping the lactate out. Other tissues in your body take the lactate up and use it as fuel-


Trevor Connor  33:00



Trevor Connor  33:00

In particular your heart. When you’re going hard, your heart almost relies exclusively on lactate for fuel. Muscles that aren’t working will take up the lactate for fuel, your liver will take up the lactate converted back to glucose. So in order to do this, that lactate has to be sent to these other tissues. This is one of the reasons that you see that optimal clearance a little below threshold because as you start getting into threshold, and higher, your body’s trying to push more and more blood to the working tissue. So it shuts down blood flow to tissues that can take up the lactate. Hence higher and higher intensities. Your ability to clear lactate actually decreases. If you’re training that clearance. If you train that ability to shunt lactate to other tissues, you’re also helping the body’s ability to get the acid out to disperse it to get it to places where your body can also buffer it and get it out of the system. If the blood flow is just to the working muscles, lactate is going to accumulate there, acid is going to accumulate there and you’re going to shut down.


Chris Case  34:06

And for anybody that wants to hear Trevor, bust the myth about lactic acid in the body, go back to Episode 30.


Trevor Connor  34:15

That’s way back.


Chris Case  34:16

Way back.


Myth Buster on Lactic Acid in the Body

Trevor Connor  34:17

The really simple explanation here is so any acid can also exist in a base form. So lactic acid is the acid form. Lactate is the base from. Your splitting hairs on this one. You know lactate and lactic acid are the same thing. It’s like no one’s a base ones. And acid is actually a very big difference here. Every acid base has a what’s called the PKA value, which is the pH at which it exists 50% as an acid 50% as a base, the PKA value for lactic acid and lactate is 3.64 that’s a really acidic solution, you drop much below seven, you better get to the hospital fast. So at physiological pH is pretty much it’s impossible for lactic acid to exist.


Chris Case  35:20

There you go. There’s the quick summary. I think there’s one more physiological effect you wanted to talk about, Trevor?


Fuel Sources for Exercise

Trevor Connor  35:25

Yeah, this is actually a really important one to a lot of people. Because not everybody is training to race, a lot of people are training for fitness to drop some weight, you are always using a mix of fat and carbohydrates for fuel, I will say you will use a little bit of protein. But that’s mostly negligible until you start getting into a very fatiguing ride, where other fuel sources start to be depleted in your body. Sure, we’ll tap into the protein. But for all intensive purposes, generally, when you’re talking about what are your fuel sources for exercise, it’s a mix of fat and carbohydrate. At low intensities, you are pretty much relying almost exclusively on fat. And there’s literally a curve, you can just look this up online, just do a search for this and you’ll find 100 different versions. But there is a curve showing maximal fat oxidation rates. Problem is as you get into those higher and higher intensities, your body shuts down use of fat. So it’s, it’s not like higher and higher intensity as you burn more and more and more fat.


Chris Case  36:33



Trevor Connor  36:33

So actually there is a point where you start burning less fat, and you just start relying exclusively on carbohydrates for fuel.


Chris Case  36:40

Right, right


Trevor Connor  36:41

And the peak of that curve is surprisingly low as a percent of your VO2 Max, which is how it’s usually expressed. Because this is measured, the way to measure is with a VO2 max test is right around 65-70% of VO2 max. So that is your good old what- what people think of as your zone two ride.


Chris Case  37:05

Mm hmm.


Trevor Connor  37:06

So actually, the chart I’m looking at is even lower, it’s saying 60% of VO2 max.


Chris Case  37:10

So two and a five zone or more model not in the polarized zone two.


Trevor Connor  37:15

So this would be polarized zone one.


Chris Case  37:17



Trevor Connor  37:18

So if you think the most people we don’t, you obviously in a bike can’t measure your VO2 max or your riding or your VO2. But your VO2 max correlates roughly with your max heart rate. So basically we’re saying 60% of your max heart rate, you do the math that’s surprisingly low.


Chris Case  37:41

Mm hm.


Trevor Connor  37:42

So if you have a max heart rate of 200, that means you are maximally burning fat right around-


Chris Case  37:49



Trevor Connor  37:50

  1. So hence the go and ride slow if you really want to burn a lot of fat.


Chris Case  37:56



Trevor Connor  37:57

That gets a little bit more complex, just simply because if you go a little bit harder, you you need more fuel. So there’s some argument for the the increased intensity, greater demand for calories is actually going to ultimately burn more fat because even though you at the moment rely more on carbohydrates-


Chris Case  38:15



Trevor Connor  38:15

Once you’re done with exercise, your body is going to try to restock those carbohydrates rely on fat. So 24 hours later, after the ride, you might actually burn more fat at a little higher intensity. But if you go out and do super high intensity, yeah, you’re relying on carbohydrates, you’re not burning a ton of fat. So those are your kind of physiological points. I hope one of the things that we got across there is again, harder is not necessarily better. And you are training different systems at different intensities.


Chris Case  38:50

Any others you want to bring up?


One of the Biggest Training Improvements: Stroke Volume

Trevor Connor  38:51

You know, there actually is one other that is really worth bringing up. This, this gets into a lot of older research. Back in the days when we believe in central versus peripheral conditioning, and well that has been thrown out a little bit. This still applies. One of the biggest training adaptations that we see is an improvement in stroke volume. That’s basically just how much blood your heart can pump out share beat. Stroke volume is also surprisingly maxed out at a very low intensity. So it’s right around 65% of your max heart rate or your VO2 max. Now you are still continuous, so this is a great example of harder is not always better. If you’re trying to improve that particular adaptation improve your blood flow, or your the amount of blood your heart can pump per beat. You’re maxing out about 65% you’re still doing just as much benefit at 85-95% you’re just not doing more.


Chris Case  39:54

Mm hmm.


Trevor Connor  39:55

And you’re getting more stress of those higher intensities.


Chris Case  39:57

Right, exactly.


Trevor Connor  39:58

So I’ve used this a lot as As an example, and people who say well, train slow and you’re getting gains, why not go that that 10-15% harder and to get more gains? And you point out, no more gains.


Chris Case  40:11

It’s a dosage thing. It’s like, you could take 600 milligrams of ibuprofen or you could take 18,000 milligrams, which are you going to take? Maybe that’s a poor analogy. But


Trevor Connor  40:24

-well another


Chris Case  40:25

-makes some sense when it when it’s looked at as a dosage.


Trevor Connor  40:27

Another good example is back when everybody discovered that caffeine is performance enhancing, and they started just mega dosing on it.


Chris Case  40:34



Trevor Connor  40:35

And it is performance enhancing. But they’ve shown basically above 200 milligrams, you seem to no more gains. So what you were having was all these people that were getting to the start line, taking over 1,000 milligrams, incredibly jittery, paranoid, everything else had already started sweating-


Chris Case  40:54



Trevor Connor  40:55

-and they’re not getting any more gains, that they would have gotten at 200 milligrams. So this is the same sort of thing, you’re gonna get the same gains, right? And 85%, but you’re doing more damage


Chris Case  41:04

and fewer side effects, if you right at that, at that rate.


Trevor Connor  41:07

Lower intensity, right? So that, I guess gets us into our next part.


How to Find the Right Range to Ride in and the Right Point in That Range?

Chris Case  41:13

All right. So with all of this information, this foundational information about the energy systems and these breaking points and things like that, how does someone out there, take that information and find the right range to ride in and find the right point in that range to right at given their objective for the day.


Trevor Connor  41:34

There are hundreds of examples we can give, let’s just give a few. And hopefully this gives some good practical advice as well. So the one I would like to start with is training and sustainability. Because that’s of all these emails that we got asking isn’t harder, better? This was the one that we got the most frequently, where people are saying, I’m doing that zone two work. And there’s just, there’s always that resistance, and I get it. And I’ve dealt with it with my athletes, I dealt with it myself until I had enough people smack me across the head and say, Trevor, stop being an idiot. And those people smacking me were very good, experienced high level cyclists and I went there smart, I’m dumb, maybe listened to them. So let’s talk about training that sustainability training that endurance system, it is that long, slow, so in the Dr. Seiler’s, three zone model, zone one riding. If you’re using more of a five zone model, this is what you would think of as zone two. And it is slow, it is easy. So there’s that temptation to say I want to sit right at the upper edge of this. So the reason we gave this whole explanation of these physiological breakpoints is remember that aerobic threshold is a break point. Something different happens physiologically as soon as you cross it. So you can say, I’m going to train right at the upper end of that range or that zone. But the point that we are making is, well, not well, but but already below that aerobic threshold, you’re maximizing that fat burning, you have maximized that stroke volume, a lot of the gains that you see, don’t increase as you get to the higher end of that zone. So this is kind of a hard concept to get. But for the most part, training anywhere within that zone two is gonna give you basically the same thing except a slightly, you’re gonna get a slightly lower score on your your training stress and whatever software you’re using. Other than that, physiologically, it’s generally the same thing. But if you sit at that upper edge, if you sit at that trying to sit right at that aerobic threshold, you are probably going to go over it a lot. And then you are seeing a shift physiologically, and what’s happening in your body. A lot of these adaptations that you see, are going to get equal benefit anywhere within that zone. But when you run that edge, you run a danger of you’re actually starting to train different energy systems, there’s a different effect on your body. And it might not necessarily be what you want, it’s not necessarily the goal that you’re going for.


Chris Case  44:23

But wait a second. So I’ve heard you say many times before, particularly when it comes to Dirty Kanza training, for example. This is a very powerful ride to train right at that aerobic threshold, sort of get right up to the edge of that range. So what what-


What Range Trevor Encourages his Athletes to Ride in

Trevor Connor  44:41

So I what do with my athletes have a tighter range. It’s very similar to at that other threshold, I had that threshold range for my athletes to work out particularly if I’m working with time trialists so it goes a little below that threshold to just slightly above to try to push that threshold up. I have I’ve read some research that shows that your aerobic threshold and your anaerobic threshold tend to move together. So if you can push that aerobic threshold up, you might also push that anaerobic threshold up, and you can do it with less stress to the system. So there is a certain powerful ride. And we’ve had pros on the show say that they do this periodically that they see the benefits to it. But it’s just a tighter it’s taken that zone two and just making


Trevor Connor  45:28

-compressing it. But I still try to keep my athletes below the aerobic threshold. So I set an upper limit in terms of heart rate, and basically say, don’t go over that. And that heart rate tends to be a couple beats below where I have their their aerobic threshold. So I’m trying to keep them under.


Chris Case  45:28

Compressing it.


Chris Case  45:47

And you’re not telling people to do that.


Trevor Connor  45:50

It’s not every ride.


Chris Case  45:51

Yeah, right. And that it’s a it’s a think of it as a workout session. In a way it’s not something to be used for every ride just sprinkled throughout.


Trevor Connor  46:00

Yep. So it’s it’s a very powerful ride, but it’s not every time. So I actually there’s a whole backstory behind this, but I give my athletes what I call LSD rides, and LSS writes. LSD rides are most of their endurance rides. And that’s anywhere in that Dr. Seiler zone one-


Chris Case  46:18

Mm hmm.


Trevor Connor  46:18

You know, there’s a point, if you’re riding at 40 watts, you’re probably not getting any gains. But it’s a pretty big range. And I just basically say, anywhere in there, I’m fine with it. I’m not going to get too particular, I have what I call an LSS ride. And that’s that tight range. And it’s not like I get my athletes that LSS ride multiple times a week, it’s a matter of fact, most the first half of the base, I almost don’t give it to them at all. It’s a ride that I bring in in the later part of the base and points during the season. Another example is training repeatability. So we talked a little bit about this with Dr. Seiler last week. And this is something that’s often underestimated. But it’s that ability not just to do an effort, but to do an effort over and over and over again. Something you hear in racing is everybody can get over the first climb. It’s who can get over the 10th climb.


Chris Case  47:18



Trevor Connor  47:19

And that’s where you start seeing a lot of difference in the fitness. And Dr. Siler talked about this a little bit last week. But sometimes, when you’re looking at your interval work, going harder isn’t always better when especially when you’re trying to train that repeatability. Sometimes as you get fitter, let’s say you’re doing four by eight minute intervals. Instead of saying next week, I’m going to add 10 watts to it, which might very well take you into a different energy system.


Chris Case  47:47



Trevor Connor  47:48

Add an extra interval. Yeah, now do five by eight


Chris Case  47:51



Trevor Connor  47:51

Train the repeatability. So that’s another good example of pushing the wattage up hidden that upper end might not be getting you the gains you want. Maybe keep the power a little bit lower.


Chris Case  48:05

Mm hmm.


Trevor Connor  48:06

And just add to it as a matter of fact, let’s throw that clip in from Dr. Seiler, because he explained it much better than I just did.


Dr. Seiler’s Advice on How to Regulate a High Intensity Session

Dr. Steven Seiler  48:13

When you go into a high intensity session, there’s two ways of regulating it. The one is to say I have a specific power or pace that I’m going to hold. So you go in there, you go into the session with this kind of anxiety, that man, I hope I can hold those 385 watts, you know. And then the other way is to say I’m going to go in, and I’m going to go on feel. And it’s going to I want it to feel hard but manageable for four times eight minutes. And that’s what I’m going to do. Well, these are two very different psychological approaches. And I think both of them have their place in a build part of the season, when you just want continuity, you want to do the work, like I’ve said this with my daughter, I said, look, just go on feel, just, you know, but let’s keep heart rate below zone five, I want you to don’t get above about 93%. You know, so we’re gonna try to be in that zone four that I talk about in a five zone model, but just go on feel and don’t worry about the the speed on the treadmill or on the track. Because that that can often become very psychologically, almost damaging, you know, if you don’t hit those exact paces, every time you do a hard session versus the you know, where you say I’m getting ready for this race, I need to hold this power. This is my time trial power, you know, where you’re very external load focused. And there’s a place for both but I think it’s probably a good idea to mix it up a bit.


Trevor Connor  49:53

I had on our list here talking about lactate clearance with time trials, but we kind of covered that. That’s maximize just below your anaerobic threshold. So there’s another example of hitting the top end of the range, you might actually be decreasing your lactate clearance not training that system as well.


Chris Case  50:12

So it was 90%?


Trevor Connor  50:14


Chris Case  50:15

About 95% is where you want to hit.


Trevor Connor  50:17

If you are a pure time trial is doing that work at low cadence. Really good. If you’re a crit rider doing that work at low cadence.


Chris Case  50:27

Not so good.


Trevor Connor  50:27

Not so good. Unless you raise crits by breaking away and just trying to-


Chris Case  50:32



Trevor’s Favorite Moment Ever in a Crit

Trevor Connor  50:33

-time to time trial away. And that is still I think I’ve told this story, but one of my all time favorite moments ever in a crit, which this is back in the 90’s, when they allow just about everything. And I lined up in a crit with a guy from town a couple towns over from where I lived, who he had unique ideas. And he decided in this crit, he was going to break away and win this crit solo. So he showed up on his road bike with a rear disc, and a front desk.


Chris Case  51:05

Oh, wow, nice, very nice.


Trevor Connor  51:07

Which they used to allow.


Chris Case  51:08



Trevor Connor  51:09

So we started, he sprinted, he got way ahead of the field, he got to the first corner leaned over his bike didn’t turn at all, he went into the hay bale. We never saw him. Again.


Trevor Connor  51:23

That’s fantastic. And his name was…


Trevor Connor  51:27

I am not telling. So we just talked about that sort of gains for time trials. But I don’t want to over emphasize that, that is great training for them. But if you want to be a good time trailist or a good breakaway rider, you also need to do significant work a little bit above that threshold. And that’s where you start training, your ability to suffer that pain to handle that-that intensity. Because if you are doing anything shorter than a one hour time trial, you want to perform well, yes. You are going to have to do that time trial a little above threshold, especially if you’re doing a 20 minute. So let’s say your anaerobic threshold or your FTP is 280. If you’re doing a 20 minute time trial, you’re probably going to target somewhere around 300-310 watts. So you do need to do work where you learn how to tolerate that sort of pain. Chris I just talked a lot about the ranges for lower intensity work. For higher intensity work, let’s use a clip from Episode 80 was Sepp Kuss, a pro and Team Jumbo Visma. More than many of the pros we’ve talked with Sepp is all about using power numbers when he trains. But knows that he still seeks certain fields and ranges. It’s not a harder is better approach. Now, what about I don’t know what type of intervals you do, but what about shorter like VO2 max intervals? So, so yeah, that kind of too.


Sepp Kuss’s High Intensity Work

Sepp Kuss  52:58



Trevor Connor  52:58

So that range.


Sepp Kuss  52:59

That’s what I was going to also men- so for VO2, for example, that’s just, yeah, I’d never feel good during those. And those are pretty much I feel pretty much all out to truly get the VO2 effect. So that is also just based on yeah, what I what I perceive the effort to be and then also what what kind of number I, I know I should be at but they never feel like they feel completely different from a threshold effort to me because it’s five minutes full gas basically recovery.


Trevor Connor  53:36

Fair enough. So you said it feels different, how do they feel different?


Sepp Kuss  53:39

Threshold for example, feels feels controlled, repeatable, you have more, I guess, mental mental clarity for for your technique, and you’re shifting and looking up the road. So I think those are, those are markers for me that I say, Okay, I’m in, I’m in a good good place right now. This is a good pace or a good power. And then for for a v2 effort, for example, which you’re, you’re kind of reaching for, you know, those those components, like your cadence, your, your choice, your technique, that all starts to, to fade a bit as that effort gets harder. But then again, that that goes to show what your what zones, you’re most comfortable. And so if you’re, you know, if you’ve been training that, let’s say that VO2 number for a while you’re going to be much more comfortable in it and you’re going to be able to execute all these I guess techniques. And then if you’re not comfortable in that zone, you’re going to start to to fade a bit technique wise, which I think a lot of people overlook.


Trevor Connor  54:46

And that’s not necessarily a bad thing.


Sepp Kuss  54:49

What lead, missing, you’re?


Trevor Connor  54:52

Losing a bit of the technique in those intervals?


Sepp Kuss  54:53

Yeah, and those intervals, I mean, ideally, you’d have full control in every every zone, you know, and yeah, I’d say for me if I’m training one, not one zone, but one, I guess, type of effort for extended period of time, I feel more in control. And I feel okay, I can, you know, play around a bit more in this zone. But if it’s like, oh, this is the first time I’ve done a threshold workout in a week, it feels very foreign. And those things like feet, like your respiration rate or your sitting standing, all those things start to feel a bit more like out of control, I guess, or something that you’re chasing a bit rather than firmly in control of.


Trevor Connor  55:41

Do you ever do? Kind of shorter Tabata style intervals? Like 40-20s 20 downs?


Sepp Kuss  55:46

Yeah, yeah, a lot of that. I usually do a lot of like, 30-30s just because they’re mentally a bit easier for me than 40-20.


Trevor Connor  55:57

What’s the, what are you seeking with those? Like-


Sepp Kuss  55:59

Just clearing clearing lactate? Yeah.


Trevor Connor  56:02

So but is it just all out? Are you still sort of pacing?


Sepp Kuss  56:06

Yeah. So yeah, definitely pacing. And then, you know, on the on the off, not letting it drop off at all really? Like keeping it at a, like a, whatever high zone two, I guess you could say? Yeah, not not full, full recovery. Really, so 540, 290, 500? You know, I’ll know with a very firm floor of the of the interval, but nothing.


Trevor Connor  56:32

So even for something that short not in town you’re still keep an eye on your power. And how to sustain it.


Sepp Kuss  56:36

Oh, yeah, definitely. Yeah. I don’t think anything I go really off of feel it’s pretty much all around. Yes.


Trevor Connor  56:37

Not all around the best?


Sepp Kuss  56:44



Trevor Connor  56:45

Is it just as high power you can use you can hit or when you’re, for example, doing the 30-30s? Are you trying to keep a consistent power?


Sepp Kuss  56:52

Yeah, that’s all pretty, pretty consistent. Yeah. Yeah. Try to keep them all the same. Same power? Yeah, I guess. I guess like a 32nd sprint would be the only thing that’s purely feel based just because you’re all out yet say everything else for me is pretty, pretty measured. But I do love doing that kind of stuff, the more up down even in my longer intervals. I rarely do one. One level power, which I mean, that’s also my racing. I guess.


Trevor Connor  57:25

That’s your style.


Sepp Kuss  57:26



Trevor Connor  57:27

Let’s return to the conversation where Chris brings up another factor with the high intensity work.


Dangers of the Sympathetic Stress and Riding at High Intensities

Chris Case  57:32

Early on, you brought up the the dangers of the sympathetic stress of riding in at higher intensities. Are there are there any others that we should mention here?


Trevor Connor  57:42

Yeah, there actually is one other worth bringing up Chris. And we talked about this in a couple episodes in particularly Episode 82, where we talked about the whole immunology side, what’s going on physiologically, when we adapt. As we go harder, we do start accumulating reactive oxygen, so we get oxidative damage. ROSS does some damage, it increases the length of time that you need in order to be able to recover from any sort of work. And you do start accumulating ROSS at lower intensity. So that sympathetic damage or effect that we were talking about, that’s a really high intensity. ROSS, you will see at some of the lower intensity. So sometimes when you’re going harder, you are really not seeing any more gains in the systems energy systems are trying to train. But you’re accumulating more ROSS. So all you’re doing is just increasing the time it takes to recover. And this is one of the reasons is also you need to be careful about always seeing what pros are doing and following the pro example. Because there there are several studies with pros showing that they had developed these amazing abilities to tolerate ROSS.


Chris Case  58:49

And the rest of us don’t have that.


Trevor Connor  58:51

So more amateur, less experienced riders. They start going hard they start doing some intensity, they’re accumulating a ton of ROSS and that’s why the next day they’re they’re feeling pretty crappy.


Chris Case  59:02

Mm hmm.


Trevor Connor  59:02

Great study showing pros. When they did a four or five day stage race, they actually their their ability to handle ROSS was so good. You saw a net decrease over the course of the race as opposed to an increase, where if you took a relatively new cyclists put them in the same scenario, they just get overwhelmed. So that’s another good reason for what we talked about pros can do these very powerful rides right around that that aerobic threshold and maybe go a little bit over and handle it. For a less experienced rider, you’re gonna see a lot more damage for the gains than a pro might see.


Chris Case  59:43

Right. Speaking of which, we tend to think of pros as machines in some way. They are capable of amazing things and capable of tolerating a lot of volume and and intensity all at the same time the rest of us, however, we’re not machines. And I think he wanted to end with talking about that point in and emphasizing that, because of that, we, it goes back to the question of where to train within these ranges.


Trevor Connor  1:00:16

I think that’s a great point. And I think this is the most important takeaway of why we really want to get across this message that it is a range, and use the range don’t ride the edges of the range.


Chris Case  1:00:28

Let’s get back to our interview with Sepp, where he describes how he paces his training intervals.


How Sepp Kuss Paces his Training Intervals

Trevor Connor  1:00:34

When you do intervals, is it purely by power heart rate? Or is there a feel component?


Sepp Kuss  1:00:42

For me I, it’s usually just by by power only, I’ve never done done heart rate. Yeah, I usually set myself up with with numbers that are pretty, pretty doable. Never really reaching for for a number. I mean, you know, some days will be harder than others. But yeah, the way I do the intervals I go into them knowing Yeah, this is a number or you know, perceived exertion that that is not not easy, but something that’s attainable, and repeatable day to day or interval to intervals. So, yes, it’s hard to describe it. But I’d say at the end of the day, I never feel like oh, that was a 10 out of 10 just awful, awful day hard. At the end of the day, it’s like, oh, that was maybe a maybe eight out of 10 difficulty. But I could do it again tomorrow. So I’d say that’s my my general. You know, feeling right.


Trevor Connor  1:01:34

You said you’re going to look at the power. Let’s say you do an intervals you say I’m going to be doing these intervals at 400 watts. Do you consider how you feel at all? I mean, if you go out and one day they’re killing you another day, they feel easy. Do you say I’m gonna ignore how that how that feels? And I’m going to stick with the 400 watts? Or do you listen to how you feel on say, maybe toda  I need to back down or today I can step it up a little?


Sepp Kuss  1:02:00

Yeah, I think usually if it takes me about, yeah, intervals, 2 intervals to truly feel how, how I’ll feel that that day or that that session or whatever. So, yeah, definitely. If I feel like crap, I think okay, well, what did I do? What was the what is the training looked like before? What-what have I been eating? And then you know, I’ll make a decision. Maybe I shouldn’t be doing the interval at all. If I feel that awful, or, yeah, maybe I should push through maybe at a lower lower power and just make that that new number, the new, you know, standard for for just that day. But yeah, it’s always a tough call. Because you always want to be, at least for me, I always want to be at the, the top of what I can do. But another component is, you know, thinking thinking big picture the word for later in the week or for, you know, the next week’s training what when you need to, when you need to do save yourself for-


Trevor Connor  1:03:00



Sepp Kuss  1:03:01



Trevor Connor  1:03:03

So going through a couple different interval types. How are you, so when you’re doing more of a threshold type workout. And I don’t know what sort of length thresholds whether you’re doing shorter five minutes, or you like the 20 minute type threshold, workout, which I’d love to hear, but how do you gauge with a threshold workout? Is it pure power? Or how do you know what sort of intensity to hold with that? And how are you pacing yourself for the workout?


Sepp Kuss  1:03:34

Honestly, it’s pretty yeah, robotic for me, I guess I say, yeah, this is this is a number and you just, you just got to do it. For me. I think there’s the mental component to it’s, it’s hard for me just to say, okay, I’m doing this number for for 20 minutes. I’m gonna say I’ll do three minutes this number with a minute, this number for 20 minutes. And then that’s, that’s easier for me to do than just staring at a line.


Trevor Connor  1:04:01

You really are a climber you like a little bit of variability, don’t you?


Sepp Kuss  1:04:06



The Thoughtfulness Side of Training

Trevor Connor  1:04:10

So there again, you have Sepp Kuss, who is a numbers guy saying, he adjust, he sees how he feels. And then he adjust the numbers. And this is important. The range changes. It changes day to day it changes over the course of a ride or what’s optimal for you. What so we can say your ranges 160 to 190. And some days, yeah, right at 190 is going to give you the best gains. But the next day, that might be too hard. Yeah, but days later, that might be too easy. That’s why you need to look at the range. Listen to how you feel and say I’m not feeling as good today. I’m going to drop it down. I’m going to go lower in the range, or you can have a day where you’re feeling really good and go Okay, I’m going to push it a little today. I’m going to push the upper end of that range. But if you just sit there and say, this is the number, I have to hit that number. Or let’s say you’re on the trainer doing intervals, and you just lock in that trainer at what you think your FTP is. So let’s say it’s that 280 and you just go, I’ve got to do 280. You’re having a bad day, you’re a little fatigued, you’re going to get disappointed, because you’re not going to get through those intervals, they’re going to feel like crap. And you’re just going to say, what’s wrong with me? I did too a week ago, am I getting less fit? No, it varies. Last week, 280 was right. This week, maybe you should have done 270. But you need to vary it. And you know, that’s a day to day thing. But even on the course of a ride, if you’re going out doing a five hour ride, 190 might be right at the start of that ride, that might be too high at the end of that ride. And we think when we create these zones, we think of ourselves a little too much like machines. And when you start thinking about the edges, I need to sit right at the edge of my zone, then you’re really turning yourself in the machine and you’re not allowing that day to day fluctuation. A good zone model is going to allow that fluctuation it is a range. And that’s why you have to look at each day. Okay, my zone two is 160 to 190. Today, I’m closer to 160. Tomorrow, I’m closer to 190.


Chris Case  1:06:25

Yeah, some people might call this the art side of training. But what it really seems to come down to is thoughtfulness you have to think about these things. You can’t be robotic about them and just say, oh, that number was put into training peaks on my plan by my coach, I will go out and I will hit that number over elts. It’s you have to make an assessment of where you’re at what happened the previous day, what happened that morning, what you ate, how hot it is how you’re feeling all of those factors come into play, when you are making that judgment call on where to ride within a range, how you’re feeling, how many repetitions, you do have intervals, all of those types of things.


Trevor Connor  1:07:09

Once again, Dr. Steven Seiler explained a lot of this a lot better than me, let’s hear his thoughts.


Dr. Seiler’s Take on the Thoughtfulness in Training

Dr. Steven Seiler  1:07:15

In a build part of the season, when you just want continuity, you want to do the work, like I’ve said this with my daughter, I said, look, just go on feel, just, you know, but let’s keep heart rate below zone five, I want you to don’t get above about 93%. You know, so we’re gonna try to be in that zone four that I talked about in a five zone model, but just go on feel and don’t worry about the the speed on the treadmill or on the track. Because that that can often become very psychologically, almost damaging, you know, If you don’t hit those exact paces, every time you do a hard session, versus the the, you know, where you say, I’m getting ready for this race, I need to hold this power. This is my time trial power, you know, where you’re very external load focused. And there’s a place for both, but I think it’s probably a good idea to mix it up a bit. And don’t always get caught up in your watts. Because you’re not going to have a great day, every day. Some days, it’s just going to be a decent day. And you just do the work and get out. You know, and accept that. And don’t take it as a as a as a crushing defeat, because that is the nature of the beast, you’re going to train 500 times this year, and they’re not all going to be great. I think that’s part of learning, to you know how training works. And I know you, you understand this, but for young athletes and for people, you know, they’re like my daughter, they’re kind of on a general climb, you know, they are progressing, and they have this expectation that every workout is going to be a new, a new top, a new PR, a new FTP, a new five minute power, you know? And when that doesn’t happen, then they what do they do? They double down. Instead of saying, you know what, I think I need some rest. They say no, I just kind of go harder. So this is the this is the danger that can you can easily fall into with all of that feedback of watts and so forth, is it you get you start to train the metrics instead of training your body?


How to Listen to The Feel

Trevor Connor  1:09:37

We have athletes all the time, email us and say I went out for a ride. I was trying to target X. And it just felt really off something was wrong. What’s going on with me? And kind of the answer here is the only thing that was wrong with you is you just didn’t adjust.


Chris Case  1:09:53

Yeah, you-you have too, you human.


Trevor Connor  1:09:55

You’re human. Listen to the feel. We sometimes get away from the field but have to listen to it. And we’ve been asked, so okay, powers fluctuating 190 is not 190 every single day. So I want to use heart rate. But then you have issues with heart rate where sometimes if you have some neurological fatigue, your heart rate is going to be depressed. If you’re riding in the heat and you get dehydrated, your heart rates going to spike. So you have to factor these things into them. But then people get kind of confused or concerned saying, but then there’s no set number.


Chris Case  1:10:32

Mmm hmm.


Trevor Connor  1:10:33

How do I know where to train? And that’s the feel. If you’re going out and doing a ride, and it’s a ride you’re used to, and it just doesn’t feel right today, when you’re trying to hit that number you normally hit. Turn around, maybe turn around or it’s just adjust?


Chris Case  1:10:52

Yeah, right.


Trevor Connor  1:10:53

I mean, if you feel absolutely awful, and you can’t, you’re doing intervals, and you can’t hit the numbers at all. And you can barely get through your first interval. Yeah, you probably fatigue turn around, go home.


Chris Case  1:11:05

Mm hmm. Yeah.


Trevor Connor  1:11:05

So you’re going out and doing a long ride. Normally, you do it at a 130 heart rate, but you just you know, it’s a hot day, and you’ve hit 130, almost instantly walking out the door, well, you can go a little higher, or you walk out and you have a little bit of fatigue. But this has meant to be a harder week might be okay, just saying today I’m gonna target 125, you have to listen to that feel.


Chris Case  1:11:29

I think this also goes back to something we’ve talked about many times before, and that is having a purpose or a goal for each ride. And some days you will go out the door. And if your goal is, is that day, well, I, this is a fatigue week, for example, I know that I’m actually supposed to be tired, and you go out and that’s how you feel. But you know that that’s right for that day, then that’s okay. Whereas on other occasions that you have to make that judgment call, again, based on the goal and the purpose of the ride.


Trevor Connor  1:12:03

Range allows you to do this. So let’s say you’re zone two is let’s give it a broader range 180 to 240, it’s a pretty big range.


Chris Case  1:12:14



Trevor Connor  1:12:15

If all you ever do is train right around 230-240, A) you’re gonna have a lot of rides or you’re struggling, B) you have no room for the good days. Most days, if I’m just feeling pretty normal, I might be targeting around 210. That’s going to be my typical ride. If I go one day and go, wow, legs are good. That’s a day where yeah, I’m going to be up around 230-240, I have that mood- room within the range to move up. I go out feeling not so great. But I still want to get the the long ride in. Now today, where am I go, you know, 190-200 sounds pretty good. But if you have that range, you can adjust, you can adjust a little bit how you feel, if you just say it’s one number, and I have to target that, you’re gonna have a lot of unsuccessful rides. Bam. We haven’t had Colby Pearce on the show in a while, partially because he’s been working hard on his new show at Fast Labs. But in Episode 72, Colby shared his thoughts on zones targeting numbers and the art of finding the right intensity. We thought it was a great way to summarize and end this show.


Colby Pearce’s Thoughts on Zones Targeting Numbers and The Art of Finding the Right Intensity

Colby Pearce  1:13:18

All mathematical models are invalid over a large enough domain. And the question is, what is their domain of validity? Pretty sure that’s more or less a direct quote of any. So what he’s saying is, when we make a mathematical, mathematical model of someone’s power zones will predict what power they’re going to get benefit from over a certain duration, which is what eye levels are, then that’s a model. And in some cases, that model might work. And it might work really well for the bell curve of athletes. But inevitably, we’ll find athletes that fall outside that curve. So just like any model these guys are using, whether it’s the PMC, which is the mother of all models, or eye levels, you have to look at those models with a bit of skepticism. And you have to understand what exactly are you modeling? What are the limits of that model? What are the limits of the domain? I think they can be useful. I have used them to guide my athletes and some of their efforts. And they can be a useful metric from time to time.


Trevor Connor  1:14:11

What’s your feeling about any sort of zone model? Zone models in general?


Colby Pearce  1:14:14

Right? Yeah I mean, what are we talking about here? I think some of it comes down to semantics. Like, like I’ve heard you say, you know, people say I was in zone two, well what does that mean? And they can’t really tell you. I think that zones can be a useful language, we have to have a common language to discuss intensity with our athletes. And I think zones tries to assume that language, there are problems with that language at times and their problems that communication. So one of the biggest problems I have with it is let’s say I get this question a lot with my athletes. Let’s say that I asked them to do five minute intervals. Ostensibly for most athletes who are relatively fit, a five minute interval is going to be close to their VO2 max power, right depending on the recovery interval, just for the sake of argument. Let’s just say that it is. So most athletes are doing five minute intervals they’re approaching VO2 power their APIO2 to power. But there’s a chicken egg thing here because some athletes will say, okay, I want you to use eye levels or I want you to use whatever wizardry you’re going to use with your magical laptop machine, and tell me what power I should be doing, quote unquote. And my response will be, well, I don’t want you to necessarily target a power on this day. Because, particularly at this time of year, meaning March, these training days are about simply doing the work. So if we want you to do work at VO2 level on a given day, whatever your power is, for that day, is what it is, I want you to ride based off your perceived exertion of what VO2 is. And I’m one day because you might be carrying some fatigue, maybe that’s 330 watts, and maybe on another day, it’s 350. And maybe another day at 360. But I don’t want you to stop the workout. If your first two five minute intervals are 335. And your eyeballs are bleeding. And you feel as though that is your VO2 level effort for the day. That doesn’t mean we’re not going to get constructive work for you to finish the workout. In fact, arguably, we could be getting really, really powerful benefit from you doing a 20 minute total load at that at that wattage. So I want you to focus on RPE. So I think where things get confusing is when people are training when an athlete a coach, writes a work-workout for an athlete or an athlete is training? Are they really trying to achieve a certain zone on power IE output during a workout? Or are they registering your own internal exertion level of that? And then when you add heart rate into that equation, which is arguably very important things get, athletes can get really confused. So then that leads to the situation where you Trevor go to an athlete say, oh, well, how is your ride the other day? And they say I did zone two for five hours, you say what does that mean? They’re like, I’m not really sure. Because at the beginning, I was doing 240 watts. And then about midway through I was down to 200. But then my heart rate went from you know, mid 120s, up to mid 130s. And then by the end it got kind of warm. And then you know, we’re going to stop for water. But I didn’t know the guy who stopped and I the other guy wasn’t really eating. So you know, I didn’t feel like I should eat because eating is cheating. And so by the end, I was doing 190 watts, and my heart rate was floating towards the mid 140s. So what we have there is a situation where, depending on you know, and then you look at their Rp. So we’ve got three different models going for how to track their zone that they were in, which one are we paying attention to? So it comes down to the definition of the semantics, it comes down to clear communication with your athlete, what does the zone actually mean? Which which which metric are we using to track that zone? Are we using power? Are we using heart rate? Are we using perceived exertion? Three different things. Ultimately, power and heart rate are simply metrics we use to to really see what’s happening inside the athlete. Their adaptation and their effort for the day. That’s and power is not the goal. I have to reinforce this in my athletes all the time. Like I don’t really care how many watts you’re doing, man. If you’re a competitive athlete, I want to see you get results I want to see you win the races you want to win or have the best performance on your day of your race that you can have. If you’re doing 289 watts or 410 I can give a shit.


Chris Case  1:18:10

That was another episode of Fast Talk. As always, we love your feedback. Email us at fasttalk@fast or call us leave us a voicemail. The number is 719-800-2112 subscribe to Fast Talk on iTunes, Stitcher, Spotify, SoundCloud, Google Play, or wherever you prefer to find your favorite podcasts. Be sure to leave us a rating and a review. The thoughts and opinions expressed on Fast Talk are those of the individual for Coach Trevor Connor, Colby Pearce, Dr. Steven Seiler, Sepp Kuss, Tom’s Skujins, Dr. Andy Coggan and Dr. Steven McGregor, Hunter Allen, Sebastian Weber and Trevor Connor. I’m Chris case. Thanks for listening!