Polarized Training – A Detailed Look with Stephen Seiler (Faster by FLO Podcast #13)


Chris: Welcome to the “Faster” podcast by FLO Cycling, the podcast where we talk about anything and everything that makes you faster on your bike. This is Season 1, Episode 13, and today we have Dr. Stephen Seiler joining us on the show. Dr. Seiler is a vice rector at the University of Agder in Norway, and is commonly referred to as the godfather of polarized training. The polarized training method is used by countless world and Olympic champion endurance athletes. Listen to this episode to learn how the polarized training method can help you become a faster cyclist.

Polarized Training Introduction

Hey, this is just Chris starting out this episode. We had about an hour of Dr. Seiler’s time, and because he’s covered the basics of polarized training on other podcasts, we wanted to save our time with him for some more interesting detailed questions on the topic. So I’m going to cover the basics of polarized training here, before we get into the show. So, what is polarized training? I think it helps to describe the standard threshold training model, or 5-zone system that most people are familiar with, to help you understand what the polarized system is. So, if you are a cyclist or a runner, there’s a really good chance that you’ve done a threshold test. If you’re a cyclist, you can do a threshold test with a power meter, and you’ll get a functional threshold power. We’ve talked about a functional threshold power on this show many other times. And if you have a heart rate monitor, you can do a similar test, and get a threshold heart rate value. So, with your threshold value, you can develop training zones.

And Dr. Andrew Coggan has his famous, you know, five-zone system, that goes from zone one to five. There are zones six and seven, but they’re roughly the same as zone five, so most people consider it about a five-zone system. And zone one is the easiest, and zone five is the hardest. So, zone one is your recovery-type effort. Zone two is your endurance effort, where you may do your long weekend rides, or race an Ironman. Zone three is your tempo efforts. That’s where you may race a half Ironman. Zone four is your threshold, that’s about how hard you can ride for an hour, and zone five are VO2 max efforts, which are very, very hard, and you may only do those for four minutes or eight minutes, because of the intensity being so high. Okay?

So, with a threshold model, you’re going to spend a considerable amount of your training time in the middle zones, zones three and zone four. Now, with a threshold model, I’m not saying that you don’t spend any time in zone one or two or five, but compared to the polarized system, you’re going to spend quite a bit of time in the middle, okay? The zones three and four. The polarized system is different, because it only has three zones instead of five. And those three zones sit over top of the five zones. And it’s going to vary a little bit for each athlete, but the rough overlay looks like this. Zone one of the polarized system encompasses about zones one and two of the five-zone system. Zone two sits over roughly zone three of the five-zone system. And zone three of the polarized system sits over roughly zones four and five of the five-zone model, okay?

Where the biggest contrast is between a threshold model and the polarized model is how much time you spend in the particular training zones. So, with the threshold model, you’re spending a considerable amount of your time in those middle zones, zones three and four. With the polarized system, you really spend little, if any at all, time in that middle zone two. The polarized system has you spending roughly 90% of your time, your training time, in zone one. So, very easy, all easy efforts, 90% of your time, and only 10% of your time in the high-intensity intervals, in zone three of the polarized system, and you really, like I said, no time in zone two, which the polarized method considers a training black hole, or a grey zone, where they say that it’s not easy enough to be easy, and it’s not hard enough to get the physiological adaptations that you’re trying to get with the higher intensity efforts. Okay?

So, how do you determine your zones one, two, and three with the polarized system? The answer to that is a blood lactate test. So, your blood…or sorry, yes, your blood has blood lactate in it. It’s a chemical in your body, and most people know it as lactic acid. So, if you do some bicep curls in the gym, and your biceps start to burn, eventually to the point of failure, that burn is created by lactic acid. Now, your body is always producing lactic acid, you know, even at walking, very easy efforts, or sitting on the couch. But until we start to accumulate a lot of it, our body is efficient enough to clear it. And it’s only at the high-intensity efforts where it starts to accumulate, and we can no longer clear it fast enough. That’s why the burn happens, and that’s why you eventually have to stop high-intensity efforts. Okay?

So, a blood lactate test is a graded exercise test. And what that means is you start at a very easy intensity. And we did a two-and-a-half minute interval, but roughly every two and a half minutes, you increase your intensity just a little bit. And at every new interval, every new intensity, you collect a blood sample. We drew it from the ear. You can also do it from your fingertip. And you take a reading with a blood lactate monitor, and it measures how much lactic acid is in your blood. So, if you plot that, you know, over time, versus the intensity, or your heart rate, your curve will start out flat. You’ll get a jump. Where that jump happens is the transition between zone one and two. So, you jump, then you flatline, and then you jump again. That second jump is the breakpoint between zone two and three of the polarized system.

So, the first jump is known as your aerobic threshold. It’s also referred to as LT1, or VT1. The second breakpoint is known as your anaerobic threshold, or VT2, or LT2. So, my study will be posted in the notes on our flocycling.com podcast page. You can look at my profile. We will describe this in more detail in the episode on how we measure the breakpoints and what the intensities are. So, that is the basics of polarized training. So, without further ado, we’re going to get to Dr. Seiler. He is a true legend of polarized training. He has been studying this for more than 20 years, and the best endurance athletes in the world, Olympic gold medalists, world champions in any sport with endurance, rowing, cycling, running, cross-country skiing, are using this type of training. So, listen to this episode to see how it can help you improve your training. Take care.

Chris: All right. So, Dr. Seiler, welcome to the show today. How are you doing?

Dr. Seiler: I’m doing great, thanks. Good afternoon.

Chris: Awesome. So, you’re originally from Texas, but you’ve been in Norway for close to 20 years now, right?

Dr. Seiler: Yeah, it’s over. It’s pushing 23 now.

Chris: Wow. Okay. Cool.

Jon: What part of Texas?

Dr. Seiler: Austin, Texas.

Jon: Austin, Texas.

Dr. Seiler: And also Dallas. Yeah.

Jon: Love Austin.

What Happens at LT1 and LT2?

Chris: Awesome. All right. So, I can’t tell you how excited I am to have you on the show today. I’ve trained and raced for years, and I started with threshold training. And, you know, there’s a lot of good principles with that, but when I did threshold training, I found myself stagnating often, and I was constantly injured. So, there were two things that kind of put me in this roughly polarized way of training, and I didn’t even know I was doing it. Because I was always injured, I went easy a lot. And just before a race, I did a lot of shorter distance triathlons. I would do these really hard sessions where I found myself doing about 10 minutes of hard work at race pace, with 2 minutes of recovery. I’d repeat that three or four times, maybe three or four times before a race. I found a lot of fitness gains with that, and I succeeded.

And after that, we started FLO Cycling, and we started sponsoring some pro triathletes, and I started training with them. And we’d go out on their long rides, and I’d be nervous that I wouldn’t be able to keep up. And we’d start, and I was kind of half-wheeling these guys, and they’d look at me and go, “What are you doing?” And I’d say, “Well, this is a endurance ride, and we should be in the zone.” And they’d just laugh at me and they’re like, “Look, we’re doing a long ride. The only objective is to ride your bike for a long time. Take it easy.” And when I applied that to my training, I got even faster and faster again.

So, for years, I thought there was something about this type of training, but I could never really assign a formula to it. And when I read about your polarized training theory, I think a million light bulbs went off. So, we got a ton to cover today. I’m super excited to have you on the show. And there are a lot of podcasts out there that talk about your background, and the general principles of this, but you wanted to talk about some different stuff today, so I wanted to get directly into the fine details. So, without further ado, let’s start the questions. And can you explain to us what happens physiologically at LT1 and LT2? And my understanding is that below LT1, you’re using almost all aerobic energy, between LT1 and LT2, you’re using a mixture of aerobic and anaerobic, and then above LT2, you’re using purely anaerobic. Is that true?

Dr. Seiler: Well, no. But we’re off to a good start.

Jon: Awesome. Right.

Dr. Seiler: But. All right. Let’s get started here. So, when we exercise, and you start working, let’s say you’re at a really easy 150 watts on the bike, you’re spinning, in that first intensity zone, below LT1, if we could go into your muscles, we would see that only a certain percentage of all those thousands and thousands of muscle fibers are actually active. A lot of them are just chilling out. They’re not doing anything. And those fibers are not individual. They’re actually bundled. They’re in motor units, as we could say. And so, the first motor units that get turned on are these slow-twitch Type I motor units. You may have heard that term, Type I.

Chris: Yeah.

Jon: Yeah.

Dr. Seiler: And those are the bread and butter of an endurance athlete. More the better, to be honest. But we have three types. We have Type I, we have Type IIA, and we have Type IIB. And the Type I are just purely aerobic. They’re made for endurance, you know, lots of mitochondria, burn fat well, and all this, so they don’t produce a lot of lactate. Type IIA are more, they’re trainable. They can go kind of either way, but with a lot of training, Type IIA start to look more and more like Type I. But they are fast-twitch fibers. And then the IIB are those explosive fibers, that are good for jumping, or, you know, getting up a tree if the lion’s chasing you and stuff like that. So, those are the three basic types. And then, as the intensity increases, slowly, the brain will recruit, of necessity, more of these Type IIA, and eventually, way down the road, Type IIB fibers, to do the job, to produce the work. So, this mix of fiber types plays into the lactate threshold. Now, up until LT1, lactate is being produced, but it’s cycling through. It’s not going anywhere, or it’s immediately entering into either other fibers, or being reconverted back, so that it can be used aerobically. So, it’s a very dynamic molecule.

And it’s not accumulating. It’s greasing the machinery, in a way, metabolically. But once you reach LT1, you start to see an increase in production, you kind of see an increase like, if you turned on the water a little bit more in the bathtub, and the drain is open, but if you turn the water on enough that there’s a little bit of an increase in the bottom of the drain, but it’s still empty. Well, that’s what LT1 you might say is representing. But you’re still easily able to get rid of the lactate that’s being produced, but there’s a bit of an accumulation, that first little increase. Okay? And then between LT1 and LT2, as you increase the intensity, you’re in this kind of compensable range. That’s a big word, but a word where, in other words, the increase in lactate production can be compensated with an increase in removal. But the setpoint keeps elevating. And so, the highest lactate concentration that stays constant, or the high… Let me rephrase. The highest power output at which the blood lactate concentration stabilizes, that’s what we call the maximum lactate steady state, and that’s also LT2.

Chris: Okay.

Jon: Yeah.

Chris: Perfect.

Dr. Seiler: All right. And then above that, here’s where I said you were wrong. Above that, you’re still aerobic, but there’s a bigger contribution of anaerobic energy.

Chris: Okay. So, there’s so much anaerobic and lactic build-up, you overdo the system and you can’t flush it out, basically? Okay.

Dr. Seiler: Yeah. But let’s not overestimate that. I mean, even at 95% of VO2 max, I mean, there’s a huge aerobic contribution, and a relatively small anaerobic contribution. But, that anaerobic contribution is a battery. It drains out. You only have so much. So that becomes the limiting factor.

Jon: Very cool.

Chris: Cool. Awesome.

Does LT2 Relate to FTP?

Jon: So, does LT2 relate to FTP at all?

Dr. Seiler: Well, this is where things get ugly, because… I like the idea of the FTP, the functional threshold power. But the problem is is that it’s, any time you use that word “threshold,” it implies a distinct barrier, a distinct non-linearity that is going on. So, threshold supply… You know, when we talk about a ventilatory threshold or a lactate threshold, we can go in and see a diversion from linearity. We can mark what it is. But functional threshold power is just an arbitrary value. It can be useful, but when people keep using different ways to get at it, it’s not going to end up being the same. So, doing a 20-minute test, versus a 40-minute test, versus a 60-minute test, you’re gonna get different numbers. So, you know, pick one.

Chris: Yeah. That’s one of the big complaints. Yeah. Okay.

Dr. Seiler: And therefore, that’s my problem with it.

How Do You Measure LT1 and LT2?

Chris: Okay. Cool. So, before this show, I did a blood lactate profile. I did almost 25 or 30 different blood lactate readings over a graded exercise test. And for anyone listening to this podcast, if you go to flocycling.com, in our podcast page, there will be a link to my lactate profile, under Dr. Seiler’s podcast. So, Dr. Seiler, you have this, and there’s a lot of ways that people estimate LT1 and LT2. One of the ways is to say that when your blood reaches 2 millimolar lactate, that’s LT1, and at 4 millimolar lactate, that’s LT2. Is that the way that you suggest people estimate those values?

Dr. Seiler: If you don’t have really good controlled conditions, then yeah, that’s a reasonable way to go. But ideally, the way we would do it is individually. For example, with your profile, which, number one, super cool that you took 25 measurements, because that’s above and beyond the call of duty. You must like pain, sticking your finger 25 times.

Jon: You should have seen his ear after he was done with it.

Chris: Oh, man, you should have seen my ear. My girlfriend is patient.

Dr. Seiler: But anyway, but it’s great, because it gives us some granularity here that we can look at, and it actually reveals some things. So, if we start from the start, it’s good to pick out that you took a resting value. I assume that you had not eaten, or done a big carbo crunch right before you took that resting lactate. It looks pretty good, at 1.3 millimolar. And then we know your maximum heart rate, which you told me was 198.

Chris: That’s correct.

Dr. Seiler: So that’s useful for the watchers to know when they’re looking at this chart. Now, you’re at rest, you’ve got a 1.3 millimolar lactate. Now, this is measured with a Lactate Plus device.

Chris: That’s correct.

Dr. Seiler: I don’t know how great those devices are. I assume that the accuracy is good. It uses a really small volume of blood, which always kind of concerns me, because that means just the margin for error is lower if there’s a little sweat drop or anything around it, but the data looks good. So, you start out resting. Then you take off with 110 watts. And what’s the first reading? It actually, your blood lactate goes down, and that’s very typical, particularly in a well-trained person. Now, your blood lactate goes quite a bit down, and the values, you’re under 1 millimolar. It may be that the Lactate Plus doesn’t get the lactate in the red blood cells, so probably, if that’s true, then these should probably be up-adjusted by, say, 25%.

But it doesn’t matter. The actual numbers don’t matter. What matters is the pattern. So, your blood lactate goes down to 0.6 millimolar, stays down there, 0.6 millimolar, 0.5 millimolar, 0.7 millimolar, 0.5 millimolar, 0.8 millimolar. And then, at about 185 watts, 190 watts, then we start to see something going on, and you start to see an increase. So, I would say that your LT1 is actually a bit under 2 millimolar, on this value. I hate to say that to you. I know it always sucks to be told that your power is actually lower than you thought.

Chris: You’re making me happy. It’s so hard to keep my wattage there, or my heart rate, at 136. I’m struggling to do that.

Dr. Seiler: In the sense that? What do you mean? It’s too easy, it’s too hard?

Chris: It’s too hard.

Dr. Seiler: Well, there you go. See, I just made your life better.

Chris: This is, like, the best part of the podcast.

Dr. Seiler: Because actually, 2 millimolar is a bit too high. I would say, for you, that 190 watts, which corresponds to about one point… you were at 1.3 millimolar. So, you basically have come back up to where you were at rest, and that was what I would call your LT1, and your heart rate is…

Chris: One Thirty-ish.

Dr. Seiler: …about 132 or something. Yeah, so it’s… in other words, you’ve been overestimating LT1 a little bit, and that can make a difference. And then, the same thing is happening for you with LT2, because when you use 4 millimolar, what I see is probably you’re hitting your LT2 at about 225 watts instead of 240 watts.

Chris: Okay, because that’s the second curve change.

Dr. Seiler: Yeah, that’s the second point where it clearly comes up. So, you see, if you… from 220 watts, all the way up to 260 watts, you’ve basically got this smooth increase. Do you see that?

Chris: Yeah, you’re right.

Dr. Seiler: And so, you just arbitrarily pick off 4, and that’s halfway up that increase. So, really, 220, 225 watts is where I would put you for LT2, and then 190 watts for LT1.

Chris: I got some work to do then, by the sounds of it.

Dr. Seiler: Yeah, but that… And this is very typical, that people overestimate their threshold values. It’s kind of a macho thing. It’s hard, you know. It’s the equivalent of, you know, doing squats and adding weight on the bar, but not going as low.

Chris: Perfect.

Dr. Seiler; And you keep adding weight on the bar, but by the time you get to the… you know, pretty soon you’re just barely dipping your butt. So, this is the same thing is, and it’s tough for people to accept, “Okay, wait a minute, I don’t have a 300-watt LT2,” you know. But it’s important if we’re gonna train at the right intensity.

Estimating LT1 without a Testing Kit

Chris: Perfect. Okay. So, we talked about this a little bit before the show. And in your presentation, it’s called the hierarchy of endurance needs. And I’ll have a link to that on our page as well, and people should read this, because it’s amazing. But there are, you use percent of VO2 max as an intensity value. And for people who do not have access to a lactate testing facility… So, they’re rather expensive to buy, and to do the test is kind of challenging. And then, you use percentage of VO2 max, and a lot of people don’t have a percentage of VO2 max value. We talked briefly…

Dr. Seiler: Right. They haven’t had a VO2max test, right?

Chris: Exactly. They don’t have a VO2… Yep. So, is there any way that people who do not have access to these technologies can estimate their LT1 and their LT2?

Dr. Seiler: Yeah. So, what I would do is, first of all, we do need some calibration here. So, we need to know the resting heart rate of the subject, or of the athlete. And resting heart rate is just what it implies. It’s, you’re still in the bed, maybe you get up and go pee, then you get back in the bed, you’re laying down, and you make sure you’re totally relaxed, and you take your heart rate. So, that’s resting heart rate. Mine is about 40. Then you need to know your max heart rate. And your… And I mean your heart rate at max in the modality that you’re training. Because it’ll be different, maximum heart rate will be different for running than it will be for cycling or swimming.

So, if we’re talking cycling, then they need to do a cycling test. You know, on their own, really warm up well, because that’s very important, and then do a progressive, kind of, almost an interval-type session, to get up to a max effort that they can sustain for three or four minutes, and just put it, you know, all pedal to the metal, and find that peak heart rate. So, let’s say, you know, my peak heart rate is 170 now, or even a little bit lower. I’m 53 years old. So, my resting heart rate is 40, my peak heart rate is 170. So, what’s that give me? That gives me 130 beats of range, 170 minus 40. If I did the math right, that’s 130. So, that means that every 10% of my increase in VO2 is associated with about 13 beats of my heart rate range. Make sense?

Chris: Okay. Yes.

Jon: Yes.

Dr. Seiler: So, then I’d say, “Okay, I want to be at 60% of my VO2 max. And I’m going to assume that my VO2 max happens at my heart rate max. So, I’m kind of pegging those two together. I’m not actually measuring VO2, but I’m measuring heart rate. So I’m going to say, “All right, I want to be at 60% of VO2 max, so I want to find 60% of that heart rate range. So I’m just going to take 0.6 times that difference, which is 130, so 0.6 times 130, should give us, like, 78?

Jon: Okay, yeah.

Dr. Seiler: And now I have to add back the 40. And that gives us what, 118? So, 118 beats per minute is going to be about 60%. And that actually looks really good for me, because it, based on what I…I just happen to know some of my watt values and heart rate values, and so forth. And it makes sense. It adds up.

Jon: So that becomes your LT1?

Dr. Seiler: Well, it could be. It could be close. I would say probably that’s reasonably close to my LT1. Because when I do low-intensity sessions, I usually end up at about 123, so about five beats higher than that.

Chris: Okay. Using that formula, my resting heart…or, my max, peak heart rate is 198, right? So, and then my resting heart rate… How do you calculate the resting heart rate? Is it an average over the night? Just, or do you just take it…

Dr. Seiler: No. That would be sleeping heart rate. Heck, if I do my sleeping heart rate, it’s 32. So I start throwing arrhythmias at [inaudible 00:27:47]. So, I’ve actually had a Holter monitor. So, no, you don’t use sleeping. You use an awake resting heart rate. And I think the best time to do that is upon waking, before you’ve got a lot of stress and things.

Chris: Yeah, in the morning.

Dr. Seiler: But just make sure you don’t need to go pee, because that’ll raise your heart rate.

Chris: Okay, okay. Cool. So, for me, we’ve got the 198, and we’re gonna go with about a 50. So, my working range would 148. Now, to get to 65% of my VO2 max, I would take the 148 times the 0.65, which gives me 96, and then I add back the 50, right?

Dr. Seiler: You got it.

Chris: So now I’m at 146 beats per minute, but we just said that my LT1 occurs around 130. What do you do in that case?

Dr. Seiler: Well, why did you choose the heart rate you chose? You chose 65…

Chris: Well, we’re going to look…

Dr. Seiler: So, your LT1 is lower than 65%. That’s just the bottom line. And believe it or not, that’s not unusual. I looked at some data from 43 moderately-trained, well-trained, or reasonably-trained cyclists that Paul Laursen did, and their LT1 was kicking in at 55%, 58%. The average was 58% of VO2 max. So…

Chris: Oh, okay. So that changes with the individual?

Dr. Seiler: Yeah, yeah.

Chris: Okay.

Dr. Seiler: If it was so easy, you wouldn’t need me, man.

Chris: Okay. So, then, okay. Let me ask you this, then, and then we’re going to get into some finer details. We’re getting in the fine details already, but… So, if we’ve determined that my LT1 occurs around 130 beats, and my LT2 occurred around, what was it? One… Go back to that document.

Dr. Seiler: Maybe 156 or something like that, 55, somewhere in there.

Chris: One fifty-six. Yeah. With changes in fitness… I get more fit, I get…

Dr. Seiler: No, I’m sorry about…one… Wait a minute, I messed up here. Probably about 145. Yeah. Sorry.

Does LT1 and LT2 Change with Fitness

Chris: One forty-five. Yeah. Yeah, no problem. So, with changes in fitness, as I get fitter, or I lose fitness, do my heart rates at LT1 and LT2 change? Or do they stay relatively the same forever?

Dr. Seiler: Well, at least within a season, they stay relatively the same within a season. So, we’ve got good studies. Lucia has done a study way back in around 2000, with pro cyclists. I believe Carl Foster did another study where they could show that the heart rate at that particular breakpoint stays stable, at least within a season, or a year. So that means you don’t need to be testing your threshold every month to have good data. Or, you know, once you know the heart rate at those two thresholds, then you can use those. Now, hopefully, what will happen is, is the power output at that heart rate and that threshold will increase.

Chris: Exactly. Okay. And then, last question for you on this section. So, for the people who don’t have the lab equipment, how can they estimate the LT1 and LT2? Is there any way with the formula that you just gave us?

Dr. Seiler: Yeah. Well, here’s where things… This is my spin. This is what I would do, if I’m your coach. I would first, if I want to find LT2… And I’m going to pretty much assume that that’s going to be your maximum lactate steady state. I’m gonna have you do an hour of power. It’s the classic. And I’m going to have you do a one-hour ride on your ergometer, and just go as hard as you can for an hour. And you will settle into a power output that will be… Because you’re reasonably well-trained, I’m going to have you go an hour. If you were moderately training, less trained, I’ll probably have you go 40 minutes. But based on the research, we see that well-trained subjects will be able to handle 60 minutes at their maximum lactate steady state. And it gives a good… So, that will give me a good estimate of your LT2, if you do your job.

Chris: And then, LT1? How do we get that?

Dr. Seiler: And man, LT1. Now, here’s… there’s different ways we could go at it. They’re all estimates, you know, because we don’t have all the equipment, but one…you know, we could say, “Well, let’s take about 70% of that, 70% to 75%.” And that’s gonna give us a good ballpark, and then we’ll adjust from there.

Chris: Perfect.

Jon: Cool.

Chris: Perfect.

Dr. Seiler: And then the other thing I would say is that what I would want to see, if I’m coaching an athlete, and I want them to clearly be below LT1, I want to see that that heart rate stays flat during the workout, that it’s not drifting up. Okay?

Chris: Okay.

Jon: One quick question about…

Dr. Seiler: So, that’s one of the quality checks I’ll make is that, you know, if they’re on the ergometer, riding for an hour at just below LT1, that heart rate should stabilize and stay flat.

Can You Measure LT1 and LT2 without Taking Blood

Jon: Okay. One quick question about testing. Are you familiar, or do you know of any non-invasive lactate testing that’s any good?

Dr. Seiler: Not that has really taken hold. I mean, you can measure saliva, you know, but not that I am aware of. I’ve played a little bit with the cuff around the leg, using the NIRS, the non-infrared spectrophotometry type of approach. But, again, the noise still is not satisfactory, I would say. And I want to be shown wrong, but so far, I still think you gotta just do the little finger stick. It’s not exactly torture. It’s not that bad.

Jon: Okay. Yeah. Awesome. Thank you.

Chris: The earlobe, for me, worked a lot better.

Jon: Okay. So, I want to look at your three-zone system, and compare it to the standard Coggan five-zone system. And in your hierarchy of endurance needs, I’m referencing page 26. And I know that your presentation had some animations, but I just kind of want to go over the general idea of how your system overlays with the five-zone system, so I can ask some follow-up questions. So, I’m showing a slide here, if you’re watching the video, but roughly, Dr. Seiler, your zone one encompasses most of zone one and two of the five-zone system, and then you hit LT1. Now, where that LT1 hits could be slightly into zone three or slightly below it, but we’re gonna go with around the break between zone two and zone three of the five-zone system. Your zone two, the polarized zone two, is about the zone three of the five-zone Coggan system, and then that’s where LT2 happens. And then from zone four up is kind of your zone three. Is that a fair estimation?

Dr. Seiler: Yeah. And it’s really not my system. I mean, this is based on physiology. It’s not magic or anything arbitrary. It is that we anchor the zones around the physiological points LT1, or VT1, and LT2, or VT2. So, those are our anchors, along with VO2 max, which is basically 100%. And Alejandro Lucia, from Spain, back in late ’90s, early 2000s, did just some wonderful studies on Tour de France cyclists, you know, the elite guys, and this was the three-zone model that he employed. So I took it from him.

Chris: Okay. All right. We will clear that up.

Dr. Seiler: And he got it from others. So this is nothing new. This is really one of the anchors of intensity distribution in exercise physiology.

Chris: Okay. Perfect. So now, I’m going to reference slide 34. It’s called “Physiological Exposure Time.” And you’re showing a lot of time in zone one of the Coggan five-zone system, about 80%. And then you’ve got zone two, there’s about 10%, zone three, four, and five. Okay. So, these guys are spending…

Dr. Seiler: Yeah. Time in zone, right.

What Is The Bottom of the Zone 1 Training Zone

Chris: Time in zone. These guys are spending a massive amount of time in zone one. And I think with all the research I’ve done, this is one of the biggest questions I have. So, if you look at Coggan’s five-zone system, and I’m holding that slide up, you can just Google that if you don’t have it. It will also be on our podcast page. Coggan defines zone one as anything below 68% of threshold heart rate, or anything below 55% of threshold power. So my question is this. We can be on the couch at rest, and in theory, be below 68% of threshold heart rate. So, where is the bottom of zone one? Because if I’m on the couch, I’m not going to get a physiological adaptation to exercise. So, for a guy like me, who has this crazy… I have a hard time holding 130 on a trainer. I get really tired. So, my question is, how low can I go and still get a physiological adaptation?

Dr. Seiler: And again, this is where things get…you know, there is no… when you look at intensity as a unilateral variable, then you make mistakes. Because if I give you a number, and I say, “Well, absolutely 58% of VO2 max, that is the lower limit.” Well, that’s baloney, and I have no basis. But if I say to you, “Probably that 58% times 2 hours might be equivalent to 50% times 3 hours,” then you start to understand me, right? So, I would probably not go lower than 50% of VO2 max as a training intensity for a healthy, you know, cyclist’s training. And if you’re that low, then probably you’re going to be doing it a while.

Chris: Okay. So, then my next question is, does where you exercise in zone one have an effect on the level of adaptation? And it sounds like it does.

Dr. Seiler: I think so. Yeah.

Chris: Okay. So, if I spend three hours at the bottom of zone one, I’m getting less of an effect than three hours at the top of zone one.

Dr. Seiler: Yeah. And why would that be true? It would be because you’re recruiting more muscle at a higher frequency of recruitment, at that higher intensity, so you have a greater metabolic flux. And we think that that’s going to influence the signals for adaptation, such as mitochondrial adaptation or capillary adaptation. So, yeah. But what we’re trying to do is stimulate those adaptations without triggering a big stress response. Okay?

Chris: Okay. Awesome.

Dr. Seiler: So, that’s one of the key things that the elite endurance athlete figures out, is that they want to stimulate peripheral adaptations and cardiac adaptations without turning on that big stress response that occurs from the threshold and above.

Chris: Perfect.

Jon: Awesome. One thing I’ve always thought about when you’re riding a bike, you know, sometimes you see people that go for long rides, if they’re doing a two-hour ride, and then you see somebody that maybe goes out for 20 minutes. The question I have is, is there a minimum time required for adaptation to occur in a zone one workout? So, if I go out for 20 minutes, and I’m in zone one, does that really do anything, or do I need to hit, like, 90 minutes before I get any advantage?

Dr. Seiler: I think 20 minutes sounds like almost a waste of time.

Chris: Sounds like Jon’s workout.

Dr. Seiler: [crosstalk 00:40:27] I’m never gonna say that training is a waste of time, but given that you train quite a bit, if you say, “Well, I’m gonna get out for 20 minutes,” then I would almost say, “Ah, just screw it and wait till tomorrow, you know, and then do a real workout.” I would be tempted to say that. But if it was a 20-minute interval session, then that would be different, but if your goal was low intensity, then you should have… In fact, if you go to some of the rowing literature, they use the term “extensive training” and “intensive training.” And I kind of like that, because in the low-intensity zone, LT1, you’re really extending, that’s what you’re trying to do, is think extending the time that you can comfortably perform at this intensity, with good technique. You know what I’m saying? That should be the mental focus is, can I repeat good technique, if I’m a rower, a cyclist, a cross-country skier, whatever it is, at this intensity, and what used to be after an hour started to feel uncomfortable, I can now go 90 minutes, or I can go two hours? You see? So, that’s the extension. You’re extending. And then the above LT1, you start thinking about intensive training, to handle the intensity.

Chris: Okay. Perfect. I’ve heard this. Have you heard of Maffetone, Phil Maffetone’s 180 formula?

Dr. Seiler: No. You can refresh my memory.

Chris: He’s a guy who says you take 180 minus your age, and that’s kind of your aerobic threshold, and you just train below that 180 minus your age. Okay. So, it’s…

Dr. Seiler: Oh, yeah. I have to just… All of these formulas are so wonderful, but they are just estimates. You know, we’re all individuals. So, I really get frustrated, because…

Chris: Okay. [crosstalk 00:42:21] Okay. Yeah. So…

Dr. Seiler: Well, let’s just take a group of 50 guys your age. They will have… you have a high maximum heart rate for your age. If we were to use 220 minus age, you should be at 184. If we were to use 208 minus 0.7 times age, you should be at about 186 or something like that. So, either way, you’re above. I’m below. My maximum heart rate has tended to be low. And the range is, like, for a given age, can be 30 beats. So these formulas are good at the population level, but they really are dangerous at the individual level. Because there will be people that they will miss big time. You know, they’ll be 20 beats above or below what the formula says. So that’s something we really need to get across here.

Chris: Okay. So, one of the things that he said, and I’m hoping you can bust this myth, but he’s saying that if you’re doing a zone one workout, the polarized zone one, he’s saying that you’re using a specific energy system, and if you just break into LT2, even for a short duration, 30, 60 seconds, that you change your energy systems, and it has a negative effect on your entire zone one workout. Is that true?

Dr. Seiler: I have no reason to believe that’s true. No.

Chris: Okay. Thank you, because I didn’t like that rule, and it sucks [inaudible 00:43:47]

Dr. Seiler: You know, but I will say that… You know, we do talk about intensity discipline, and it’s easy to start drifting up in intensity. So, the mental idea of trying to be disciplined and not sneak up into these higher zones is a good idea. But I don’t think the one minute in zone two, you know, obliterates the value of the 60 minutes before that. Not at all.

Polarized Training and Elevation

Chris: Okay. Perfect. And then, last question on this section about zone one. So, heart rate is affected by elevation and hydration. Is our blood lactate, or… So, I live at sea level. So if my LT1 occurs at 1… let’s call it 130, and then I go to Park City and I’m mountain biking with my friend. Should I do any adjustments at elevation when using these LT1, LT2 principles?

Dr. Seiler: Well, the first thing you should do if you go to altitude is you should make sure that the first few rides you do are just easy. That is just… you know, our basic rule when we take elite athletes up to altitude is that their first, at least four days, are just low intensity. They don’t do anything above LT1. And then, after those initial days, they’ll start to introduce some intensity. So that’s the biggest thing to tell you, is just don’t go up there and go off on a hard ride, because that’s a good way to dig yourself a hole pretty quickly.

Chris: All right. Cool. My buddy Brad’s listening, then he knows we can’t go hard the first few days [crosstalk 00:45:32]

Dr. Seiler: That’s just the rule of altitude training for elite athletes, is it’s a great way to get in trouble if they go out too hard in those early sessions.

Chris: Okay. Cool. Let’s jump into zone three. Jon, go ahead.

Is Work Above Zone 3 Irrelevant?

Jon: LT2 defines the bottom of zone three. Is it safe to assume that the top of zone three is irrelevant? Like, is there a max top?

Dr. Seiler: Well, the top of zone three is VO2 max and heart rate max. So, it’s worth knowing that, that max heart rate is max heart rate. But, having said that, I would say that most of the training, if we look at our best athletes, and we look at the intervention studies that we’ve done, both point in the same direction, that the best value for effort is in that range from just above zone… the upper edge of zone two, in other words, that transition, to, say, halfway. So, that 87% to 92% range, if we were using heart rate max. You know, doing a lot of work at 90% is preferable to doing a little bit of work at 95%.

Chris: Okay. So that leads to my next question. We’re gonna talk about, you do intervals in zone three. So, you’re saying that the ideal intensity for zone three work is that 87% to 92% of VO2 max?

Dr. Seiler: That’s what we see is that in the long haul, if I’m coaching athletes, I’m going to tend to prescribe longer intervals, I’m going to try to get them where they can accumulate 30 to 40 minutes of work time. When I make that prescription, they’re going to end up around 90% of heart rate max. And if they try to push harder, they’ll bog down. And so, it’s a natural, when we’ve done this in intervention studies, and prescribed, say, four times eight minutes, with two minutes recovery, then that interval session, they’ll solve it, and they’ll end up at 90%.

Using Power with Polarized Training

Chris: Okay. Perfect. Let me ask you this. A lot of times, people use power as a measure of intensity because heart rate lags. Is there any way to use power for that intensity?

Dr. Seiler: Oh, yeah. I mean, if you have the luxury of good power measurements, stable, consistent, you know, like your own ergometer, or so forth, then they’re great. And once you calibrate it… So, when I do, for myself, like, I’ve done some work on the ski ergometer from Concept2, and submitted my times and all this, so I have trained a bit. And yeah, I peg a certain power, and I believe, four interval sessions. Once you know about where your goal power is, then you should just use power, and not heart rate.

Chris: And is there any way that we can calculate where that 87% to 92% of VO2 max is based on the test that we’ve done? Or do you have to get your heart rate up there and then see where the power is?

Dr. Seiler: Yeah, that’s a good… There’s different ways to go at it. But I think, for example, what I would do, probably, is first, I would say, I would give yourself a prescription. Let’s say four times eight minutes. Two minutes of recovery. So, now I’ve given you a prescription, and what I’m going to tell you is solve this prescription. I want you to do four interval bouts. Each one of them lasts eight minutes. You get two minutes recovery between. Do them as hard as you can, such that the average power for the session is best possible. So, what’s that mean to you? That means don’t fly and die, don’t do the first one so hard, right? And don’t start too easy, and try to bring it all home at the end. But go steady, hard, four times eight minutes, and then find out what… And then you’re going to zero in on that power, and then measure your heart rate. And that interval session will give you a good indicator of where you are. And then you adjust from there. So, that’s what I would do, is start with a prescription that tends to put people in the right intensity range. And we have pretty good data on that.

Polarized Training Intervals

Chris: Okay. And then your intervals, I’ve heard you talk about 4, like, 4-minute intervals, 8-minute intervals, and 16-minute intervals. Those are kind of your recommended ranges to get the time you’re looking for?

Dr. Seiler: Yes, yeah. I mean, there’s nothing magic about these times. But, based on everything we know, we tend to favor not doing too much shorter than three or four. And so, 4, 8, and 16 has just been a kind of a nice symmetrical kind of approach for us.

Chris: Perfect.

Dr. Seiler: And we’ve got very consistent data. We’ve prescribed these hundreds of times in total. And we kind of know what’s going to happen, and what ends up happening is, is four times four, it’ll put them in zone five, it’ll put them in… It sucks, it hurts, their RPEs are high, their blood lactates are, like, 12 millimolar, 13 millimolar. If we prescribe four times eight, it’s tough, but their RPEs are a bit lower, say, 16, 17. Blood lactates, about 9 millimolar, and heart rates about 90%. And then if we put them at 4 times 16, they end up being at their maximum lactate steady state. So they’re at about, you know, 87%, 88%, of heart rate max, or at about, for cyclists, about 6 millimolar, 5, 6 millimolar blood lactate, and their RPE is 15, 16. So, it’s predictable.

Chris: Awesome. Okay. Let’s talk about the rest really quick. I’ve heard you say that two minutes is kind of the sweet spot. Any more than that, you don’t get a benefit, less than that, it’s not enough. So, two minutes is what you recommend for rest?

Dr. Seiler: Yeah, we’ve published a study on that, where we, you know, kind of did it pretty reasonably, and that’s what we found. And we’ve been doing it for years. So, two to three minutes, you don’t really need more in a typical interval session.

Chris: Cool. And then do those two minutes count as high-intensity time or not?

Dr. Seiler: No. I would just count… What we tend to do in Norway… There’s different ways of counting, you know, measuring things, but what we tend to do is called “modified time in zone.” So, if you were to actually take the heart rate data, and plug it into Polar Flow, or whatever you use, you would get time in zone. And the time in zone would end up being less than the actual time of the interval. But what we do is we just square off the curves. So, four times eight, we just say that’s four times eight minutes in zone four. That’s 32 minutes, zone four.

Chris: Gotcha. Gotcha. Okay. Let’s get into building a training plan. Jon, go ahead.

Polarized Training After Injury

Jon: If you think about starting polarized training, it could be in a couple different situations. Number one, you’re new to a sport, you’ve not trained before, or you may be coming back from injury. Is there any benefit to spending 100% of your time in zone one, for a certain time period, just to sort of get yourself back in the groove of things before you start adding in zone three work?

Dr. Seiler: Yeah, that’s… I’m thinking about myself, and I hated it when I got injured and was coming back and everything. And so I know that nobody is gonna want to do a whole bunch of zone one for eight weeks. I think eight weeks was maybe something you suggested. But I think that a few weeks, two or three weeks of trying to really focus on just getting back that basic rhythm of training, is probably a good idea.

Chris: I must be an oddball because I love zone one work, and I came back from injury, and I’m actually eight weeks into this type of training, and I’ve done all zone one work.

Dr. Seiler: Well, that’s great. You know, my problem is I’m the natural interval guy, so I solve everything with an interval session, if I’m not, you know, really paying attention to my own research. So, that’s my problem.

Chris: Okay. Cool.

Jon: If you have started a little bit slower, like you’ve suggested, and you do start adding in zone three work, is there any benefit to gradually adding in zone three work, where you’re not moving right away to that 20% time?

Dr. Seiler: Yeah. Well, you just touched on something that’s important for us to go into, and that is this 80/20. It has been made pretty popular, and like most things that get made pretty popular, it becomes partly mythological. So, the original recommendation was based on sessions, counting the number of sessions that were performed with the primary intent of either being low-intensity, threshold intensity, or high intensity. So, that was the original research that we did, and we said about 80% of sessions, training sessions, should be below the threshold.

Chris: Oh, wow. Okay.

Dr. Seiler: And then we’ve carefully done studies to show what’s the calibration between time in zone, session goal approach, and so forth. And so if you count minutes with a Polar Flow or whatever… I’m not trying to advertise Polar Flow. It’s just the one that’s coming to my head.

Chris: [inaudible 00:55:34]

Dr. Seiler: You’ll end up with about 90% time in zone for an 80/20 session distribution.

Chris: Ahh. That makes a lot of sense. Okay. Cool.

Dr. Seiler: So, it’s hard to collect 20 minutes at high intensity. I mean, 20% of time. That would cook most people.

Chris: Okay. That clears a lot up, actually. Okay. Cool.

Dr. Seiler: Okay.

Polarized Training for Amateur Athletes

Jon: So, some people that have spoken against this method have said that it only works for professional athletes who have endless time to train. And so, do you have any…

Dr. Seiler: That’s just not true. I gotta be honest, that’s just not true. So, we’ve done a number of studies on sub-elite, way sub-elite runners, and cyclists, training in this range of four to seven, eight hours a week. And we see that it does help, that, very typically, these athletes are doing just too much training in the threshold range, and their intensities loading is too monotone.

Chris: Okay. Cool. So, even at four hours a week, you’re still seeing benefits?

Polarized Training and the 90/10 Rule

Dr. Seiler: Yeah. And here’s the deal. If I can only train four times a week, all right, that’s a limitation, because I would probably get better if I could just train more. But, given that limitation, let’s say it’s four times a week, and, I don’t know, seven total hours or something for cycling. Then I’m going to at least make sure one of those sessions is long, at least as long as is manageable for me. So that’s going to be that long weekend ride, because I want to get a lot of zone one. I want to get that extensive training. So, instead of evenly distributing the time across those four sessions, I’m going to front-load one of those sessions and try to get it to be much longer. And then maybe two sessions are going to be just hours, you know, one hour each on the road, and then that third session is going to be a really good interval session, using long intervals, getting into that 90% sweet spot, and collecting minutes, because that’s gonna be race-relevant.

Chris: Okay. And then, because it’s 10% of your time, for a guy who’s training seven, eight hours a week, he’s only looking for 45 minutes of intervals, 30 to 40 minutes of intervals.

Dr. Seiler: Yeah. And that’s exactly what… That’s one really tough session.

Recovery with Polarized Training

Chris: Okay. And that’s one a week? That’s cool. Okay. You answered my next question perfectly. Okay. So, a lot of programs talk about a recovery week, every three to four weeks. Do you agree with that? And if so, what reduction of volume should you use?

Dr. Seiler: Yeah. You know, some of the studies we’ve done, we had this huge study on cyclists a couple years back, three years back now. And we did a 4-week, you know, we did 12-week study, but it had 3 micro cycles where we did 3 up, 1 down, and then tested in that fourth week before we started a new cycle. And it kept the guys healthy, and it kept them… We measured their stress and everything, and stress went up for three weeks, and then it came back down to kind of normal level in that fourth week. So, yeah. I think that’s a good basic rule of thumb, is that, you know, you can handle three weeks of intensification of the training, where you’re comparing this week’s interval session with last weeks’, and you’re trying to increase the wattage, and, you know, you can do that about three weeks in a row, and then you tend to kind of hit the wall. And so, yeah, three up one down, and then how much do we drop it? You know, there’s different ways to do it. You could just say that week I’m not going to do a high-intensity session, or you could say that week I’m going to drop my volume by 30%. You know, kind of play it by ear a little bit in terms of what’s the stress factor for you and what’s your week look like and so forth, so that you truly are reducing the stress.

Polarized Training vs. Base Build Peak

Chris: Perfect. Polarized training doesn’t really have the same base, build, and peak periodization that you see with a threshold type training, and I’ve heard you say that things get more polarized the closer you get to a race. Can you just define that briefly, what you mean by that?

Dr. Seiler: Yeah. If we look at our top athletes where we’ve got lots of really good data on there, you know, push into a championship, where they won a gold medal, what we’ll see is, is that they will be, let’s say, you know, in my five-zone model, where I take that zone one and break it up into two, and then zone three is exactly what it, is between LT1 and LT2, as always. And then, above the LT2, I break that up into two zones, four and five. So, that’s the way I do it. We create five zones. That’s the Norwegian model, anchored around LT1 and LT2. You with me?

Chris: Yeah.

Dr. Seiler: So, back to the question, then, then what we’re going to see is, is that as they’re approaching a championship, they will be even more on the lower end of that zone one, meaning they’ll be more zone one, almost no zone two, no zone three, and then, the training that typically would be in zone four, some of it will edge up into zone five.

Chris: Okay. Perfect. Perfect.

Dr. Seiler: So, it’ll be like, it’ll go from a lot of zone two and four, or one, two and four, to zone one and five. If that makes sense to you. That would be a polarization of the training as they’re approaching a championship.

Polarized Training and Tapering

Chris: Makes perfect sense. And for tapering, is that the same kind of advice you give for people who are tapering, but now you’re going to reduce volume as well?

Dr. Seiler: Yeah. With tapering the work of the guys like [inaudible 01:01:45] that have really worked on tapering and looked at this, is the basic model for tapering is maintain your high-intensity frequency, but decrease the number of bouts, so that… You know, like, if, instead of four times eight, you might do two or three times eight. And then, reduce volume. How much depends a bit on what you want, and how you…you know, maybe you reduce volume by 30%. But again, we’ve seen different… The way people actually do this depends a little bit on how much racing they’ve been doing. You know, the classic tapering studies have been based on doing one big championship. Whereas a lot of cycling athletes are racing every weekend. So, we have to keep this in mind, is that the tapering process probably is different for the athlete that’s doing a lot of racing versus the athlete that’s peaking for one big event.

Pacing and Polarized Training

Chris: Perfect. Okay. And then, what’s your best advice on pacing? Is there any way to use LT1 and LT2 for pacing? Well, let’s look at a short distance race like a sprint triathlon, an hour-ish, and then an Ironman, a full, you know, 8-hour, 12-hour day?

Dr. Seiler: Well, hour-ish is maximum lactate steady state. You know, you’re basically right on your redline. So, you’re gonna see guys around 90% of heart rate for that hour. That’s just the way it’s gonna end up looking. You know, it’s tough. It’ll drift. So, it’ll maybe start out at 88%, and it’s gonna be drifting up. And by the time they’re going across the finish line, they’re at 96%.

Chris: Yeah, I’ve been there.

Dr. Seiler: But the average is gonna be around 90% for that one hour. And then, you said Ironman, well, you know, Ironman, now you’ve got to be able to metabolize a lot of fat. You’re not going to be able to hold threshold intensity for eight hours, at least not the average guy. So, a lot of that work is going to be a little bit below LT, or right around LT1, I suspect.

How Often Do You Need To Measure LT1 and LT2

Chris: Okay. Perfect. We’re the last couple questions before we get to our watt point question. How often should we repeat a blood lactate test if we’re doing them?

Dr. Seiler: Again, the heart rate is going to be pretty stable. And if you’ve got good power measurements, if you’re in a situation where you can measure power at home, or you’ve got it on your bike, then probably you don’t need to do that very often. But if you are in an environment, training environment, where you’re just having trouble getting good numbers to get some anchor points, then maybe you do it more often. For cyclists, I don’t see why it would be necessary to do it very often, given they have SRM and all this stuff.

Staying Below LT1 for Beginners May Mean Walking

Chris: Yep. One of the potential problems that has occurred with some people using this method is that when they start, they’re so out of shape that if they’re trying to run, or if they’re trying to ride a bike, that they can’t actually do it while staying below LT1. What do you recommend for somebody like that?

Dr. Seiler: Polarize your training. I know that sounds terrible, but the fact is, and we’ve seen this on studies, is we get these guys, these 35, 40-year-old guys that come in, they’re gung ho, they train five hours a week, and every ride is just half wheeling to the max. And they come in, and they’ve got 2.5 millimolar before they put on their skin suit, you know. And they end up in this hyper… They don’t have any metabolic control. And so, the first thing we see is, is that if we just tell them, “All right. You’re coming in the lab two times a week. You’re going to do these tough interval sessions. So by all means, when you’re not in the lab, train easy.” All right. So, that’s the first thing we tell them, and that all kind of automatically pushes them into this polarized situation, because those two sessions for them are tough. And so they end up actually training really easy otherwise, and all of a sudden, things start changing. Their resting lactate comes down, they start to normalize the profile, if we get, you know, six, seven weeks of that, and it makes a difference.

Chris: Okay. And that might be walking, for runners, right?

Dr. Seiler: Yeah. Maybe. Or, you know, walking up… I hope not. But definitely running slower than they’re used to for a little while.

Chris: Okay.

Chris: Okay. All right. Last question. We ask this to every guest. It’s called our watt point question. And the idea is if the listeners take the advice of the expert on the show, how many watts can they add to their FTP over a season? So, we always use an athlete with a 300-watt FTP. So, let’s assume that that athlete is following a threshold-type training plan, and then adopts a perfectly prescribed polarized training plan for a season. How many watts do you think they could add to their FTP?

Dr. Seiler: Oh, wow. You really put me on the spot here.

Chris: Not an uncommon reaction to this question.

Dr. Seiler: You know, I’m gonna say that if you let me train you, I can get 5% to 10% out of you.

Chris: Wow.

Dr. Seiler: Five percent. I can make a 5% difference if I can get you to do things in a more disciplined way. Then 300 goes to 315.

Chris: Beautiful, beautiful. Okay. Is there anything… How can users find out more about you, or how can we help you out? Is there any pages that we should go or check out? What can we do to find out more about you and your system?

Dr. Seiler: Well, I’m on Twitter. I used to say I would never tweet, but there’s actually a significant sports science community and endurance community on Twitter. I got about coming up on 6,000 members there, or followers, I think they’re called. And then I’m on ResearchGate. And ResearchGate is, if they want to read the geek, actual research that I’ve done, the papers that are behind the presentations, then they can go to ResearchGate, and get them for free. They can download them for free.

Chris: Awesome.

Dr. Seiler: So, you know, it’s transparent. And then, of course, there’s lots of presentations and videos and stuff on…and also some PowerPoint presentations that I’ve also put on ResearchGate. So, most of the stuff that I know, you guys can know, too, by just going to either ResearchGate or Google.

Jon: Awesome.

Chris: Perfect. All right. Well, I can’t thank you enough for being on the show. This has been a mind-blowing episode for me. It’s answered so many questions. And I know for sure our listeners are gonna love this. So, thank you very much. Back to Norway.

Dr. Seiler: Well, great. You did your homework, man. I’m impressed.

Chris: I tried. I tried, for sure. So, have a great day, and I think we’re interrupting your Stage 7 of the tour, so…

Dr. Seiler: Yeah, so I’ve gotta go check out who won.

Chris: All right, man. Take care, and thank you so much.

Dr. Seiler: You bet. Bye-bye.

Chris: Thank you for listening to this episode. Be sure to listen to Episode 14, where we interview Nate Pearson from TrainerRoad, to learn how his experience racing Leadville can help you go faster at your next ultra-endurance event. If you enjoyed the show, please help us by sharing our podcast and by leaving a rating or review. If you want to learn more about our company, FLO Cycling, please visit us online at flocycling.com, that’s flocycling.com. You can also find us under FLO Cycling on Facebook and Instagram. Until next time, ride safe.