Comparing Training Methods Across Endurance Sports, with Dr. Stephen Seiler

Dr. Stephen Seiler helps us explore the similarities and differences in physiology and training methodologies in running, cycling, cross-country skiing, and rowing.

cross-country skiing
Photo: Thomas Dils on Unsplash

While the Fast Talk podcast was originally geared toward cycling, many of the concepts we discuss can be applied across all endurance sports. After all, when we discuss human physiology, the principles remain the same whether we’re talking cycling, running, rowing, or cross-country skiing.

Today we’re joined by someone who has a broad understanding of endurance sports, not only because he’s studied human physiology in the lab for decades, but he’s also worked with athletes across a broad range of athletic pursuits and participated in many of the sports he studies, from rowing to cycling.

With the help of Dr. Stephen Seiler, we compare and contrast endurance sports as whole, exploring everything from cardiovascular hemodynamics to muscle loading. We also discuss training impacts and implications across sports—how similar are they, how different are they, and does the polarized approach work for all of them, and in the same way?

While we had him, we also asked Dr. Seiler to answer a few questions we get asked a lot about the polarized approach, including what intensity should 4×8-minute intervals be done at and should we ever do sweet spot work. And just to be clear, when Dr. Seiler discusses “threshold” sessions, he uses the research definition, which is actually sweet spot training—cyclists think of threshold sessions differently. [See The True Definition of Threshold.]

Adding to our conversation today are Adam St. Pierre, the head coach of the Nordic ski team at Montana St. University, Joe Gambles, a longtime professional triathlete and coach, and Glenn Swan, a former national master’s cycling champion and Coach Connor’s mentor.

To all the runners, rowers, skiers, AND cyclists out there, let’s make you fast!


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Episode Transcript

Chris Case 00:12
Hey everyone, welcome to Fast Talk your source for the science of endurance performance. I’m your host Chris Case. While the Fast Talk podcast was originally geared toward cycling, many of the concepts we discussed can be applied across all endurance sports. After all, human physiology remains the same whether we’re talking, cycling, running, rowing, or cross country skiing. Today, we’re joined by someone who has a broad understanding of endurance sports, not only because he’s studied human physiology in the lab for decades, but he’s also worked with athletes across a broad range of athletic pursuits. And he’s also participated in many of the sports he studies from rowing to cycling. With the help of Dr. Stephen Seiler. Today, we compare and contrast endurance sports as a whole, exploring everything from cardiovascular hemodynamics to muscle loading. We also discuss training impacts and implications across sports. How similar are they? How different are they? And does the polarized approach work for all of them, and in the same way? While we had them, we also asked Dr. Seiler a few questions we often get asked by listeners about the polarized approach, including what intensity four-by-eight-minute intervals should be done at and should we ever do sweet spot work. And just to be clear, when Dr. Seiler discusses quote, threshold sessions, he uses the research definition, which is actually sweet spot training. Cyclists tend to think of threshold sessions differently. We’ll clarify all of this and much more on the show today. Adding to our conversation today are Adam St. Pierre, the head coach of the Nordic ski team at Montana State University, Joe Gambles, a longtime professional triathlete and coach, and Glenn Swan, a former masters national cycling champion and coach Connor’s mentor. To all the runners, rowers, skiers, and cyclists out there. Let’s make you fast.

Chris Case 02:20
Hey Fast Talk listeners, our big off-season sale ends in just a few days. You can join Fast Talk Labs for half price and get full access to all our sports science plus member pricing on all our solutions and services like inside testing, sports nutrition consoles, and more. Join now during our special once a year offer to enjoy pathways, new workout ideas, expert sports nutrition strategies, new data analysis techniques, hundreds of the best guides and training science from World Class experts like Joe Friel, Dr. Stephen Seiler, Sebastian Webber, Julie Young, Dr. Stephen Chung, Julie Emerman, and many Fast Talk guests.

Chris Case 03:02
Dr. Stephen Seiler, It’s a pleasure to have you back on Fast Talk, welcome.

Dr. Stephen Seiler 03:07
Well, thank you. It’s good to be back. I was feeling a little neglected and forgotten to be perfectly honest, I thought, hey, well, I’ve gotten old. I’m old news. They’ve moved on.

Chris Case 03:19
We know you’re a busy guy, but the invitation is always open for you to join us here. And today, this is one that offline we’ve talked about doing for quite some time because you aren’t just someone who studies the sport of cycling. The Fast Talk podcast began a bit cycling, heavy cycling centric, but a lot of the concepts we talked about are universally applicable to endurance sports generally. And I know you’ve studied a lot of the great Nordic skiers, runners, cyclists, rowers, and so we want to dive into endurance sports generally, and talk about some of the training characteristics that are present in all endurance sports. so we can talk to that broader community. If you wouldn’t mind in a nutshell, what is your vast experience when it comes to studying endurance sports?

Dr. Stephen Seiler 04:13
Oh, man, yeah, I just love the competitive aspect of it. But I’ve worked with speed skaters. I’ve worked with rowers. I’ve been a rower myself, I’ve been a cyclist myself and I’m working with cyclists now. I’ve studied cross country skiers and I’ve skied enough that I managed to do a 50-kilometer skiing race. So I’ve kind of touched into a lot of different sports and I’ve always been fascinated with this kind of a comparative physiology approach. And then at different times, different organizations have asked for various help or connection so, I have dug into some of the issues on different sports and this was really fun to be able to do this with you guys to talk about some of these similarities and some differences. There are more similarities than there are differences, I think that’s important to say starting out is that fortunately, the basics are the same.

What Is The Definition Of An Endurance Sport?

Trevor Connor 05:12
I’ve really been looking forward to this because the comparison of the different sports is always very fascinating. I really do want to talk more specifically about some of these other sports. And, you know, the thing I actually wanted to start out with here with you is this definition because getting ready for this episode, I went back through a whole bunch of studies that compare the different sports that talked about endurance sports in general, with the question in my head of Well, how do they define endurance sports? And what surprised me was I didn’t find a single study that just defined what is an endurance sport? And I think that’s an interesting question. Because endurance sport can be what Chris did,- which is go to Iceland and ride all of Iceland for 11 days- But if you look at energetics, it’s actually surprising how quickly you go from relying mostly on anaerobic metabolism to relying on aerobic metabolism. So obviously 100-meter sprint is pretty anaerobic, but 400 meters, 800 meters, are those endurance sports? What are they?

Dr. Stephen Seiler 06:24
I’m going to make this simple for you, Connor, I’m gonna give you two variables that I think- because I thought about this, and there’s lots of ways you can spin it but- first of all, I would not say that if you just touring around Iceland, I would not say It’s a sport, but it’s an endurance activity because there’s no winner or loser there. There’s no finish line, other than a finish, but not a who finishes first. So the first thing I would say in the endurance definition is that it’s an endurance sport, if it involves getting from A to B, faster than some other individual or group or team. So it is a transportation activity, essentially, I couldn’t think of an endurance sport that doesn’t involve starting one place and transporting your body another place

Chris Case 07:16

Dr. Stephen Seiler 07:18
Yeah, but it’s still true. You know what I mean, it’s virtually you’re still doing it. So there’s a distance that’s being covered. That’s the first thing because otherwise people could say, Well yeah, but soccer is an endurance sport. They’re running? Well, no, it’s not an endurance sport. It’s a sport. It’s a team sport that has an endurance component. I want to distinguish between those where we’re going to define endurance. So we’re saying that is the key component, that’s the key differentiator. And then the other variable is duration. And you were touching on it, as where does the duration line go, and it’s a bit fuzzy, but you start to transition to predominantly aerobic energy metabolism, already at about three minutes. In fact, you could even say two, but I’m going to go three or four, and say, anything from these 1500 meter events- you know, three, four-minute events and up,- I’m going to say that what we see is the basic training, characteristics actually are much more similar than they are different. So transportation, A to B, and, let’s say, three, four minutes plus in duration, and you see a lot more similarity than you see differences.

Chris Case 08:40
I just want to clarify one thing about my Iceland trip, there was a competitive aspect because I did it with somebody else. And every day, at the end of the day, we’d look at our Garmin, and Matt would say, how long did you ride today? And I’d say I rode this and he’d say, oh, man, and then we’d ride around in circles wherever we were campground

Dr. Stephen Seiler 09:02
No way.

Chris Case 09:03
Seeing who could last the longest after a 12 hour day we’d see who had

Dr. Stephen Seiler 09:09
But weren’t you riding together?

Chris Case 09:12
Yes we were. Hopefully Matt is listening and I’m teasing him right now.

Dr. Stephen Seiler 09:16
So you had some differences in the GPS?

Chris Case 09:20

Dr. Stephen Seiler 09:23
He was correcting for the GPS error.

Trevor Connor 09:27
Their competition was who could eat more Snickers.

Chris Case 09:30
There were many hidden competitions within that but yeah,

Dr. Stephen Seiler 09:34
well yeah, there’s always hidden competitions. There’s races within the race just to qualify. But I’m trying to define this based on what the audience sees not on what the audience is not allowed to see.

Chris Case 09:48

Trevor Connor 09:49
I know we’re many weeks past the Olympics, but I record the Olympics and I’m still catching up on it and quite interesting.- This was not intentional. -This morning, the session that I was watching They had the 5k race. And then they showed the finish of the women’s marathon, which is in kilometers, about 40 kilometers.

Dr. Stephen Seiler 10:11
Around 42.

Trevor Connor 10:13
What surprised me was- I mean, obviously, the 5k was faster.- But just watching it on TV, it looked about the same even though there’s a dramatic difference in the distance. The running style was very similar, to me, they looked like they were going about the same pace. As I said, I know they weren’t.

Dr. Stephen Seiler 10:32
I can even help you because you’re right, and the difference in velocity, because we’ve studied it. I went into the IAAF data, and found about 40 women and 30 men,- I can’t remember exactly how many- that were in the top 500 in the world, and who had done the 5000, the 10,000, half marathon and the marathon in a single year just to get this picture. The difference in pace between a 5000 and a marathon, on average was only 13%.

Trevor Connor 11:07

Dr. Stephen Seiler 11:09
So you know, it is a very narrow band of velocity, compared to power in cycling, I would think, it’s a narrower velocity band than it is a powerband in cycling. And there’s reasons for that. But anyway when you’re looking at elite marathon running, they’re technically not running very differently than they would be if they were running a 5000. And, in fact, at the world-class level, they may put in surges that are 10k speed, you know.

Trevor Connor 11:44
So we’ve defined endurance sports, as you are competing with somebody to be faster to get from point A to point B. and Duration, we’re saying needs to be at least three minutes, is there anything else that we would put in this definition?

Dr. Stephen Seiler 12:01
Not anything that comes to mind right now. And to be fair, if you look at the Olympics, and you look at the endurance menu, almost all of the events, say a couple, are in the window of three minutes to two hours. So they’re all in that, you might say, pretty high-intensity band where you’re at threshold or above. The Olympic triathlon is being completed under two hours, mountain bike race is under two hours, the only one that doesn’t fit in there is the road race in cycling, which can be a six-hour event in the Olympics. But of course, it will be very stochastic in power output. So the point is, the Olympic events that you’re watching, they’re not ultra events, they are high-intensity endurance events, essentially. And that’s partly because of television

Trevor Connor 13:05
People only watch for so long.

Dr. Stephen Seiler 13:06
yeah, we don’t have the short-term attention span to deal with a six-hour race usually. Although, you know, Cycling is the one exception that I’m able to see in the Olympic menu. So it definitely is in that classic range of endurance events, four minutes to two hours.

What Is Cardiovascular Hemodynamics Role In Endurance Exercise?

Trevor Connor 13:29
So I think we’re gonna dive into the physiology now. But there’s kind of two big questions I feel we want to answer in this episode. One is comparing the different sports and how similar or different their training is. But I also think it can be very interesting to talk about. The difference between you have somebody who, we’ll use cycling as an example. You have a track athlete is doing a four or five minute event and you have a road racer who is doing a six-hour event, how similar or different is their training as well. So let’s dive into the physiology and you throw a big term at us when I asked you what you’d like to talk about. So you said, Let’s discuss cardiovascular hemodynamics.

Dr. Stephen Seiler 14:14
Yeah, that’s a good starting point. I mean, I would argue that the default position for the human is upright running. If we think of an evolutionarily supported position, meaning that our adaptations over time have been optimized for that transition to an upright position and running. So I think that’s the default and the reason I say that is because once we understand that it tells us a little bit about some of the hemodynamics. Now, you live in Colorado, I am from Texas and Arkansas. In that area, most places where the land is flat or fairly flat, you’ll see water towers right? you know what I’m talking about? You can see them on the horizon in flat places, and we’ve got the name of the football team or whatever, go Wildcats. And what’s the purpose of the water tower? Well, the water tower elevates the town’s water supply, creates a gravitational load so that it pushes the water down and that creates enough pressure to drive it, getting the water out to all the sinks and toilets in a town. And that is analogous to the heart pumping water out right? There using a static pressure, but we use the pressure of the heart. But the other pump that we don’t think about very much -that’s true both in town and in our bodies -is you got to get that water backup to the to the tower, you got to reload, you got to recharge the tower. And that requires an actual pump. And in the human body, it is the muscle pump. The muscle pump facilitates, it really helps to bring back blood flow from the extremities. So when we’re running, every time the muscles contract, it helps to squeeze that blood, that venous blood back up vertically towards the heart, it helps venous return. And so you could say that the running motion, the running contraction pattern, all of that it all fits together in an optimized way for the cardiovascular system to function, just like that tower and the pumpworks for the water department in your hometown. You need both, because it’s a closed system, and they both are necessary. You need the pressure from the tower and you need the pump to bring back the water. So now when we get out of that position, then things change a little bit. Does that makes sense?

Chris Case 17:06

Dr. Stephen Seiler 17:08
So we can get into a little bit of it. I mean, but the basics are the same. But the subtleties change a little bit in terms of hemodynamics. And it manifests itself in different ways that your body position if you’re on the bike and you sit up, your heart rate will tend to have a brief increase, right? And as you get down on the drops, your heart rate may actually go down if you’re holding the same power. That’s not because it’s easier but because there’s a change in that relationship between venous return, blood flow back to your heart, and stroke volume and heart rate.

Do Different Activities Have Different Impacts On Hemodynamics?

Trevor Connor 17:50
Adam St. Pierre is both an experienced exercise physiologist and Nordic ski coach, let’s hear what he has to say about the impact of the different endurance activities on hemodynamics.

Adam St. Pierre 18:01
Like typically, cross country skiing gauges more muscle mass than cycling, right? Because we are using upper body. There’s a lot of core engagement for propulsion, in addition to the lower body movement. So in many cases an equivalent workload or equivalent lactate production will see a a higher heart rate in cross country skiing compared to cycling. Again, because of that increased muscle recruitment, whole body, as well as the posture. The heart has to work a little harder to pump blood up to the brain in an upright posture compared to like swimming, or cycling where you’re in more of a horizontal posture. So there’s some general rules of thumb you can utilize when trying to equate workload in one sport to workload in another. And the rule of thumb, we used to estimate at the Boulder center for sports medicine was, if you want an equivalent workload cross country skiing to cycling, you probably add anywhere from five to 15 beats a minute, to the heart rate target you would use for cycling. So for an easy ride, you’re going out and targeting 140 beats a minute, 150 to 155 is probably an equivalent workload for cross country skiing. What a lot of less proficient cross country skiers notice is that it can be really hard to work easy. Because of the technical demands. It’s similar to swimming, I get in a pool and I’m working my absolute hardest and I’m not moving anywhere. So you get on your skis and you can just flail around and work perfectly hard, but not move particularly fast. So in cross country skiing, we’re trying to have the balance of technical proficiency and just maximal aerobic power output. Like swimming is a very technique intensive sport. Whereas cycling, yes, there’s some technique involved, but most would agree it’s generally an engine sport, you’re trying to get that engine as big as possible. Well, we also want a big engine for cross country skiing, that big engine doesn’t do a heck of a lot of good unless you can use it to produce power in a way that will move you forward. So we do a lot of technique work, our training this time of year is fairly balanced between classic roller skiing, skate roller skiing, and running. And then some athletes will utilize cycling as a sort of an additional aerobic workout when they have extra time. But we’re able to, we call it, ski imitation, bounding or ski walking. And that fits in well with run training. And then we do our technique work real specifically on roller skis. So roller skiing is a great way to improve your technique. But it also requires you to be fairly proficient on your skis, or you risk falling. Falling on snow as a relatively low impact, you’re not gonna lose a ton of skin and chances are you won’t get hurt. Falling on roller skis has a slightly higher level of consequence, much like road cycling, you go down, you’re losing some skin, and there’s potential for greater injury when you look at it.

Trevor Connor 21:32
And I remember some of my early physiology classes, the way it was explained to me is, humans are designed to either be moving or essentially laying down because when you’re lying down your body no longer has to fight gravity, the blood can get back to the heart much more easily. But when you are in the standing position, you need to be moving to get those muscle pumps working. And actually I don’t know why they put this on one of my physiology books, but they mentioned that there was an old form of torture where they would just make people stand without moving at all and eventually they pass out because all the blood would pool down in their feet.

Dr. Stephen Seiler 22:13
That’s also called guard duty.

Trevor Connor 22:15

Dr. Stephen Seiler 22:18
It’s a modern form of that. It’s orthostatic intolerance, venous pooling, and a fainting reflex. So the brain basically protects itself.Evolution has equipped the brain with a way to say you know what, if I’m not getting enough oxygen, than I’m just going to make you lie down. And then you do, and so it is a fairly failsafe method for rapidly returning adequate blood flow to the brain. And the brain decides, it’s the decider and it says my blood flow is a priority. And so we have various reflexes including the fainting reflex and the pushing reflex which will just drive blood pressure up crazy to get blood flow to the brain during times of stress ord in a situation where not doing so can lead to death. So we’ve got a lot of these you know, we’ve got a lot of this evolutionary baggage that helps us to survive under conditions that perhaps aren’t so normal today but those reflexes are still relevant when we’re exercising.

Trevor Connor 23:35
And a quick side note or tangent since we’re on the subject, we have little one way valves in our venus system because the muscles can pump that blood back up but in between the muscles contracting, gravity could just pull that blood back down. So those one way valves then close and keep the blood higher up. And that’s one of the reasons if you get massage or if you’re doing foam rolling, you only ever want to put pressure towards the heart because if you massage away from the heart, you can damage those valves.

Dr. Stephen Seiler 24:07
Yeah, it’s a great point and it also feeds Another issue is that as we get older, there is a risk of blowouts and you start to see guys like me. That have some vein in their calf or their leg that looks kind of like it’s gotten wiggly, it’s no longer smooth and straight. It’s it’s kind of become like a Alpe d’Huez hairpin curve and that is a vein that is basically blown out and those valves aren’t working anymore. And I have one because of a blood clot that happened to me, but it’s fairly common. I see quite a few middle aged endurance athletes and I’ll see a calf and I’m like, yeah, they gotta blow out. And then you wear the pressure socks, and stuff to help keep blood from pooling in the calf or so forth. So all this stuff fits together and it’s part of that basic understanding of the hemodynamics. And hemodynamics just means the movement of blood in the system, and what are the various variables that are influencing that relationship between stroke volume, -which is the amount of blood being pushed out each beat,- and heart rate. And you put those two together, and you get cardiac output, which is oxygen delivery, I mean, that’s essentially putting the limitations on oxygen delivery. So understanding these basics is pretty valuable information for any endurance exerciser, because that’s your basic pump, it’s worthwhile to know how that pump is working.

What Does Cardiac Output Look Like In Different Sports?

Trevor Connor 26:01
Yeah, I’m glad you brought up cardiac output, because stroke volume and the rate of the heart. So the full cardiac output that is not sports specific at all, in any endurance sport, you’re hopefully going to improve that cardiac output. But when you get to the actual oxygen delivery to the muscles, that can be a little sports specific. So for example, Cycling is almost exclusively your legs. So you’re going to really see the body focus on oxygen delivery to those muscles, where if you’re doing something like nordic skiing, you’re using your full body. So there’s going to have to be delivery to all muscles, which is certainly going to both impact heart rate and also impact any sort of peripheral adaptations. So I guess that’s the next question to you is what is general? And then how does the individual sports impact this oxygen delivery?

Dr. Stephen Seiler 27:03
Well, it’s a great question. And it’s a fun one too, because, again, you can kind of get into this evolutionary aspect and say, Well, we’ve gone from basically being four limb to two limb dominant. And so when you put athletes in that four limb situation where all four limbs need blood flow at the same time, like in cross country ski, then you really put the heart under duress. I mean, you’re challenging blood flow delivery, because now you’ve got to open up the valves to multiple limbs at the same time. This is one of the more challenging cardiovascular situations, and I think it’s one of the reasons why we tend to see some of the biggest Vo2 max values in cross country skiing. Because it is that Quadro paddle situation, that will create the greatest amount of muscle mass, that’s active at the same time. Rowing is also a Quadro pedal situation, but you’re sitting down. So that kind of changes again, the hemodynamics a bit. So I always found when I was doing cross country skiing, and trying to climb up a hill, I just thought man, this is the hardest thing to do from just a straight up feeling it in your lungs and in your heart standpoint. If that makes sense? Whereas when you move to cycling, or skating the amount of muscle mass that is active is smaller. So it almost feels more acutely limited by what’s happening in the local muscle. Does that ring true for you?

Trevor Connor 29:01
No, that makes a lot of sense. And that raises the question of -so particularly if you’re using heart rate zones to train- can use the same heart rate zones for all the different sports or is that going to become more sport specific?

Dr. Stephen Seiler 29:18
Yeah, that’s a good question. And there’s been a fair bit of research on that and what the basic rule of thumb is that running ,in general, running will elicit the highest maximum heart rate. And in particular, running up a grade, so if we want to make sure we get a good maximum heart rate test, we’re gonna have people run on a hill, or do a couple intervals on a hill and then do an all out effort on the hill or on a treadmill and so forth. Most people will get their highest heart rate then especially if they’re untrained. And in most studies, even if they’re trained, there tends to be a small difference. Running will be maybe five beats higher than cycling or 7-8 beats. And then compared with swimming, running maybe 10 to 12 beats higher than what we would see as a peak heart rate for swimming, a peak heart rate for cycling and then a max heart rate for running. And this is so typical that we even use those terms peak and max, whereas peak is the sport-specific maximum or the highest heart rate you see in that modality. And max is just true max, it’s the highest heart rate this athlete sees in any activity. Okay? So you’ll see a lot of that peak versus max and the reason that is there is because there are differences from sport to sport, if you’re a triathlete, or if you’re just a recreational athlete, and you’re going to run and you haven’t been running in a while. You’ll probably feel like your heart rate is just way too high. At first, because your body’s just not used to running number one. And number two, there’s some hemodynamic differences, meaning heart rate tends to be higher anyway.

Gambles Gives Examples Of Pacing Effort In Different Sports

Trevor Connor 31:15
Joe Gambles, a former professional triathlete turned coach is used to needing different ways to pace efforts depending on the sport. Let’s hear some of the ways he addresses that challenge.

Joe Gambles 31:26
For running its pac and heart rate, obviously, and the best gauge of that is an open half marathon sort of effort and look at what your average heart rate is for that. So you can pull that data from maybe a 70.3 race that they’ve done recently- you could get them into a running race or something like that and use that data. -But yeah, definitely things like your heart rate in running is is a lot higher. You’re using a lot more muscles and probably generating a little bit more heat and in triathlon on the running is last. So at that point dehydrated, you’re running at the hotest part of the day. So it’s difficult, I think, in running pacing is probably more important, I think. I look at it two ways because as a professional you know you need to run this pace to be competitive. When you’re coaching an amateur, they sort of know you can use more like metrics like heart rate to sort of give them a guide because they maybe don’t know what their limits are. Whereas professional, they know what their limit is and what they need to do.

Trevor Connor 32:41
Runners tend to talk more about pace.

Joe Gambles 32:44
they do

Trevor Connor 32:44
When they’re prescribing a workout it’s do this at your 10k pace, do this at your marathon pace, and it’s amazing runners ability to really just go Yeah 10k pace I know exactly what that is.

Joe Gambles 32:55
You won’t see that many runners using heart rate like you’ll see a lot of triathletes and professional triathletes using heart rate in running. I think heart rat in triathlon, it’s a great indicator of how fatigued you are as well and that’s obviously another tangent but like for me if my heart rate wasn’t responsive it means I was in the depths of fatigue and I needed to have some time away and rest

Are there Different Zones For Different Sports?

Trevor Connor 33:26
I was actually just talking with an athlete a couple weeks ago who was a pretty well trained runner and had just taken up cycling. I felt bad for him because he knew his running heart rate zones and when he got on the bike he tried to train at the same zones he was asking me am I a wimp here? That’s killing me to try to hit those same heart rates.

Dr. Stephen Seiler 33:47
right exactly

Trevor Connor 33:48
And my response was you need to adjust your zones and he just gives me this look of what are you talking about? I don’t get it- like cycling zones and running heart rate zones are different and you just saw this look in his face of Ah ha. Now it all makes sense.

Dr. Stephen Seiler 34:03
An epiphany. Yeah, and it’s double jeopardy if you’re going from running to cycling, because you will be used to a higher heart rate anyway, just because of those so called hemodynamic issues I was talking about plus you won’t have the local muscular adaptations. So you’re hitting your so called threshold power, at a much lower heart rate, then you feel like you should be and it gets better if you keep cycling, of course. And what we see with really well trained triathletes is those differences start to really shrink. So there is a training issue and in cross country skiing the parallel is that if you compare their VO2 Max skiing with all four limbs or running, it is obviously higher than if They’re just using their upper body like in double polling. But when they’re really fit, and it’s race season, that gap shrinks, so their upper body capacity gets closer to their whole body capacity. It’s one of the key signs we see is this athletes ready to roll? They’re ready for the season. Because they’ve added in the specific upper body training on the snow.

Chris Case 35:26
Maybe this is a silly question. But just to be clear, the heart rate zones that you’re talking about between the different sports, there are clear differences there. What about the two thresholds that we often talk about do those shift similarly?

Dr. Stephen Seiler 35:46
Yeah, they do. Again, the amount of shift can vary depending on the level of the athlete and the amount of in the amount of training that they’re doing, you know, these elite triathletes are doing so much training in all these different modalities that they are so well trained peripherally, that there’s very little difference in either the max heart rate or the thresholds. But for most of us, that are focusing on one or the other, we will see a difference if I go out running now, my threshold heart rate is going to be low in running, relatively speaking, because I’m better trained for cycling. So there’s a specificity issue. If you have a top train cyclist, they won’t necessarily have as high of a VO2 in running (VO2 Max). If you have a top train runner, they’ll tend to have an under performing cycling VO2 max. But if you have a top train triathlete, there will be very small differences. So you can even out the gaps. And that’s why my take home message to people would be look guys are ladies, if you’re going to do multiple modalities, and you want to get it right, then you need to be conscientious of these differences and adjust, adjust the heart rate, you can expect that the cycling heart rate will be a bit lower at first, if you’re a runner, and you’re transitioning to cycling, and doing both to you know, get your expectations down, and go on feel at first. And then as you go on feel, then you’ll start to see okay, 130 on the bike feels like about the same as 142 on it, when I’m running,- you know, or something I’m just making up some numbers, -but you can calibrate, at least initially just using your good brain that perceives that, you know, this feels about the same these two heart rates, but they’re not the same heart rate. But when I’m at this heart rate for running and this heart rate for cycling, it feels about the same, about the same degree of uncomfortableness or whatever. And so that’s a decent way to get started with making that calibration.

Chris Case 38:06
And that I think goes to the importance of having a good sense of yourself. Knowing what something feels like whether it’s on your own scale, -but you know maybe more So that RPE scale that a lot of us are familiar with, that Borg came up with many years ago,- and having an anchor for what that feels like, what a three is, what a seven is what that means on the on a run, what that means if you’re out cross country skiing, etc, So that you can make those transitions back and forth between the different sports more, a little bit easier.

Dr. Stephen Seiler 38:47
Right. And like your friend said, you know, am I a wimp? No, you’re not a wimp, the answer is almost always that you’re not a wimp, it is that you are experiencing a difference in your local fatigue in your local training adaptations. And it should make you appreciate how well trained you are in that thing you’re used to, because that’s why you’re feeling such a difference. So you’re not a wimp, but you are specifically trained. Yep. And that specificity does matter.

Are Central And Peripheral Conditioning An Outdated Way Of Thinking?

Trevor Connor 39:20
So that gets me to the second part of that question that I asked a few minutes ago. You know I think this is getting a little outmoded. I’m interested in your opinion on this, but they used to talk a lot about central and peripheral conditioning and central is going to codeword for that cardiac output where peripheral is the muscles ability to take in and use oxygen. And I know that a lot of that older research they really felt central conditioning isn’t that specific at all. You can train it in any sport and it’s going to transfer to the other sports but peripheral conditioning is highly specific. What’s your feeling about is? Is that an outdated concept or still highly relevant?

Dr. Stephen Seiler 40:02
Well, I do think that the very black and white distinction that we use to say well, interval training is is central stimulation, we’re trying to increase stroke volume and low intensity is peripheral. That’s just not true. I mean, it’s just not black and white like that. We see a lot of overlapping, and I’m going to introduce for at least a lot of you a word. This is the word of the day for you. It’s called symmorphosis, functional symmorphosis, you might say, a symmetry of our morphology, symmorphosis.

Trevor Connor 40:40
You have no idea how upset I am about that, because we’ve used that word in the show, I cannot pronounce it. And you just did it so easily.

Dr. Stephen Seiler 40:49
Yes. Well, I am a professor Trevor. So that’s the key difference.

Chris Case 40:53
He’s very worldly too, he’s got a lot of languages rattling around in his head.

Dr. Stephen Seiler 40:57
Oh, yeah.

Trevor Connor 40:58
When I was, doing my master’s, I had to do a presentation on it. And I spent the whole night before my presentation not going through my notes, but practicing pronouncing that word.

Chris Case 41:09
Give it a shot.

Trevor Connor 41:12
I can’t I always go- sim morph, like I stumble.- No, I was saying you were being quite elegant. I interrupted you. So please, if you can get back there go ahead.

Dr. Stephen Seiler 41:21
Yeah, but this big term functional symmorphosis, it’s in the comparative physiology literature. But what it basically says is that there is a certain degree of elegant connection between the adaptations at the cardiovascular level, and the adaptations at the peripheral level, they’re connected, and they are in tune with each other. So, you don’t see huge differences, you’re not going to see an athlete that achieves incredible adaptations at the local muscular level, and their heart is just crap. You know, it doesn’t work that way. There is a symmetry that happens, kind of naturally, as a function of the training process. And we see it in nature andyou don’t see an overdeveloped heart relative to the musculature, you don’t typically see a massively overdeveloped musculature from an endurance standpoint and then a heart that is just totally untrained, it cannot happen. Essentially because they are both active during every training session. So they they co adapt. Is that make sense?

Chris Case 42:38

Dr. Stephen Seiler 42:39
You can’t separate them. So when I’m training, low intensity, 70%, heart rate Max. I’ve still got a high stroke volume, I’m still stretching that heart muscle with every beat, I’m still generating a stimulus that maintains or increases the cardiovascular adaptations. And when we talk about cardiac adaptations, we have to again, see that there’s an elegant symmetry, because it’s not only the heart getting literally bigger,- meaning it scales up it’s ventricular volume,- but there’s more blood. So if you got a bigger pump, you need a bigger volume of blood in the pump apparatus, and the body says, well, then I’ll make more blood. So that is happening at the same time there is a symmetry or a synchronization between these different adaptations. They’re all being connected.

Trevor Connor 43:36
Well, so the thing I want to throw in here as well, which gets it another side of the elegance you brought up. -Wait for it.- Symmorphosis

Dr. Stephen Seiler 43:51

Chris Case 43:51
Got it well done

Trevor Connor 43:53
Thank you

Trevor Connor 43:54
So certainly when I read some of the old research on that what it came, some of it, came out of is there was this question in oxygen delivery of what is the limiting step from when you breathe in oxygen to when the lungs deliver it to the blood to the cardiac output to the muscles taking up the oxygen. There was this long standing question of what is the rate limiting step? And I read a great paper on symmorphosis that basically said there isn’t that everything is equally developed because our bodies are remarkably efficient. And why would you have one part overbuilt, that just can’t be used. So they’re all essentially on an equal footing.

Dr. Stephen Seiler 44:44
Yeah, that’s a great example. I think that’s important to remember, the body is super efficient. And so it doesn’t keep adaptations that aren’t needed. And it doesn’t create adaptations that aren’t needed either. So an exception to this- humans can mess this up like in horses where we are artificially shifting the balance.- So horses have through essentially our long term genetic manipulation. Horses have an overdeveloped heart relative to their lung capacity. And so thoroughbred horses have just incredible hearts. Genetically they don’t get heart disease, the heart is what has been adapted for cardiac function. But unfortunately, what has resulted is is that you get frothing at the mouth, you get horses that really struggle when they come over the line because their cardiac capacity, their blood delivery to the lungs is outpacing the capacity of the lungs. And then they get edema in the lungs, and they get a lot of problems. So that is an example that doesn’t happen in nature, but it has happened due to breading.

Trevor Connor 46:04
Interestingly, in terms of being overbuilt, there are only two animals on the planet that have overbuilt lungs. And that’s humans and Pronghorns.

Dr. Stephen Seiler 46:15
I did not know that. Pronghorn antelope while there you go. Yeah, and we do have a bit of an overdevelopment ,the reason we say that’s true is as you know, we can do a maximum ventilation test and have just people voluntarily breathe as fast and hard as they can for X number of seconds and you can calculate their maximum ventilation volume. And then you can have them do a VO2 max test on a treadmill and you measure their ventilation during that test. And what we see is that with untrained people, there’s a big gap, you know, they might have 150 liters a minute, maximum voluntary ventilation, and they only come up to 120 during the test. So they’ve got a reserve of ventilatory reserve capacity, meaning it’s overbuilt relative to their heart, but then you take the elite athlete and you find out that that gap has been significantly reduced. In fact you can start to see some so called desaturation, where the lungs are starting to reach the point where they’re not able to fully oxygenate the blood going through the lungs because this athlete has got a 40 liter per minute cardiac output and he’s moving – it’s usually guys because they got the biggest hearts relative to body size- They’re moving more blood through the lungs then the lungs can fully saturate with oxygen. But untrained for most of us like you say there is a relative surplus and that’s why people can survive after having a lung removed, you know, because that other lung can actually keep them going pretty well. And they can even run a marathon with one loan. There’s this wonderful article I was just reading this week and I put a tweet about, I think it’s from 2018 but it’s by a guy with my same namesake Stephen Vondasva, a Dutch guy, and he really gets into the weeds about what is happening at the muscular level and the adaptations that we see. He took 13 cyclists they varied from specialists on road cycling to track cyclists, time trialest, to sprinters. What was interesting was is that these guys vary quite a bit in their specialization, but when he looked at their fiber type as just one example, the difference between these elite level road cyclists they worried about 70-30 -excuse me 60-40. No wait I’m gonna mess this up.- Slow twitch was about 70% fast twitch was about 30%, on these elite level distance athletes so 70% slow 30% fast. But then the sprinters who are these elite sprinters meaning they should be kind of the opposite. They were at 60-40. So it was only a 10% shift in fiber type that was distinguishing the road specialist from the track sprint specialist. So that tells you in my mind, it was very interesting because it tells you how subtle the set of adaptations are at the muscular level. You know, you’re moving lactate across fibers and you’ve got all these capillaries and you’re just shifting the balance a bit in the adaption in the movement of oxygen and lactate across these different kinds of fibers, and that shift in the balance is enough to distinguish a sprinter who makes a living, doing 10 second Sprint’s from a road cyclist that makes a living doing 40 minute climbs. So I think that tells us a little bit about the elegance of the adaptive process.

How Differently Do Our Muscles Fire Depending On Our Modality?

Chris Case 50:23
We talked a little bit about some of those, those cardiac differences and all the while I’m thinking to myself, this probably has something to do with the difference in how muscle firing patterns take place in different sports, how we move in different modalities. Sometimes we’re sitting on a bike, sometimes we’re holding our own weight while we run etc. So I think it’s time we turn our attention to muscle loading and muscle function. Maybe started us off Dr. Seiler by saying I’m wrong or right, that it does have a lot to do with the way we move and the way the muscles are firing.

Dr. Stephen Seiler 51:05
Yeah, I’m gonna agree with you 100% that that’s where a lot of the variation is, it’s a lot of the subtlety and fun. If I was going to try to, you know, do some basic delineation of saying Yeah, okay, what are the differences? Well, one is this loading eccentric concentric part, which is running, there’s a lot of pounding on the legs there. Every time you step, the quad muscles are basically shock absorbers. So most of their function is to eccentricall compress, they are receiving the load, and then as you roll through, you go over to a concentric phase where you’re pushing backwards against the ground, and that’s the glutes and the hamstrings. So you got first shock absorption, and then a push. And so what happens during a run, you get fatigued, the shock absorbers start breaking down and they start hurting like crap. If you run it on asphalt, especially and particularly if it’s a long run, if it’s a 40k, then you get a lot of muscle damage, you get sore, right? You get sore doing squats, and so forth. Well, cycling, you don’t have that. You got just the concentric phase. No eccentric loading, no stretch, no tearing of the muscle, no macro tearing of the muscles. So that’s one of the big differences straightaway is just that basic pattern of stretch, contractin running versus just contract- contract in cycling. And in practice, I would say that one of the things it does is it makes runners more susceptible to the hard sessions, they need not only that recovery from an energy standpoint, and an autonomic nervous system standpoint, but they just need to repair muscle damage. And that’s not as prevalent for the cyclist. So that’s one of the things I see when working with runners is that maybe they sense the fatigue in their legs more easily. Just because they’re feeling it as actual, you know, the legs are hurting, because they really pounded the heck out of them doing 20 times 400 meters on a track or a long road run. And the cyclist will be able to get away with multiple days in a row. They’re fatiguing, but they’re not feeling that fatigue that will tell them take a rest day. So that’s a that’s a clear distinction. The other more subtle distinction that I would say is the duty cycle, or I call it the push and glide versus staccato rhythm. So if you’re talking cross country ski, rowing, speedskating, you get this whoosh, you get this hard push and glide. And you get into this rhythm where the push comes and then you got a long glide phase. So you’ve got a longer recovery phase between each muscle contraction. Okay? versus running, or cycling, which is more staccato, Actually, both of them are at if you count both limbs you are about 180 cycles per minute, right? In running, we typically say a cadence of 180. But they’re counting both limbs, whereas in cycling, we’re counting one, and we’re saying 90 is typical. So it’s actually the same. I don’t think people think about that too much, but it’s 180 contraction cycles per minute you know, if you count left plus, right, well, that’s really staccato. There’s not a big gap or a big time delay between each one. Whereas if I’m rowing, on an easy day or a low intensity long row, I’m down at 18 strokes per minute. So it’s like whoosh, and then glide. Whoosh. Glide. So the force signature is very different. Does that make sense?

Chris Case 55:25
It does.

Dr. Stephen Seiler 55:25
And this is a gearing issue, if you think about it, in these push and glide sports, you can use gearing to control intensity, you have a lot of modulation in the frequency of contraction. So the rower can modulate between way down at 15, which feels- it’s tough, because you got to really balance the boat as you glide, you slide back up to the cab-, and then you’re up at 45, so you got a three fold change in frequency from the lowest cadence you might be at to the highest. Same thing in cross country skiing, you watch the really good skiers, they are really slowing down on the flats, when they’re just working on their weight transfer from leg to leg, they’re pushing off and they’ve got the smooth glide. That’s one of the things that distinguishes the really good ones is they’ve got such good balance, that they have a long glide phase, whereas the Putz like me, our center of gravity is kind of in between, and we’re not gliding long enough on one ski. So, push and glide is one difference, and that creates the potential to control your intensity with the frequency. And then you try to keep the force signature, at least at a decent quality all the time. Okay? And so that’s one of the things I talked about with athletes in terms of intensity distribution, the only thing that may be problematic for someone that’s trying to Row, or kayak or something. They say well, I’m going to do this polarize model, but I can’t paddle at a low enough intensity, because then I’m not actually technically rowing very correctly, or I’m not paddling correctly. And to that I would say, yeah, then you need to at least get your technique where you have enough force going through the movement, that it translates up, that the technique is the same at low intensity as it is at high intensity. Does that make sense?

Trevor Connor 55:33

Dr. Stephen Seiler 56:00
And so that’s an issue with these pushing glad sports, is rhythm. And that’s why they’re wonderful. Because when you’re in the rhythm, and it’s working for you, it gives you a feeling that I am sorry, I just can’t get from running or cycling, because there’s so much there is that beautiful rhythmicity to it. But it’s also a gearing thing. And it’s something we use consciously in the intensity control. Whereas in running, you wouldn’t, if you’re running slow, you’re at 170 cadence and if you’re running really fast, you’re at 195. So it’s not a big range. And not a big difference. The frequency is part of the picture, but it’s not a big part, it’s mostly just pushing harder each step. Makes sense? Same for cycling, essentially, you’re not dramatically changing your cadence, you are a little but not a lot. You’re just pushing harder on the pedals.

Trevor Connor 58:53
Let’s hear again from Adam St. Pierre as he gives us more details as a ski coach on the challenge of cadence at these more staccato type activities.

Adam St. Pierre 59:02
When you look at running or cycling, they’re talking about stride rates or pedal cadences in the 80 to 90 sometimes 90 plus range whereas rowing I think optimal is like 28 to 34 strokes per minute. But of course it depends on what the other people in the boat if you’re doing a eight man or multi person boat. Swimming is somewhere in the middle in terms of stroke rate skiing is totally variable. Typically, you have your energy production, your propulsion phase and then you have your glide phase and depending on the terrai, the type of snow, ski preparation, athlete fitness, athlete balance. Two athletes can be going the same speed and going at very different cycle rates. So, these are all factors that we practice in training. So we try to teach skiing as gears -and this is similar to to cyclists we’re not talking about, an 11-28 or something but -you’ve got different gears for different speeds essentially and the speed is dependent on terrain and snow conditions and athlete proficiency. But your slow speeds you may use a diagonal skate or a herringbone technique depending if your skater classic which might have your arms and legs moving independently, kind of like running running up a hill. In less steep terrain or in faster conditions, you may use a V1 or an offset type skate technique, or you may use a diagonal stride in classic. And then different techniques for faster and faster techniques all the way down to a to a tuck, when you’re going down a hill and it no longer makes sense to continue to use energy to produce power, you just get into your most aerodynamic position and hang on. So in doing so, we think of cross country skiing as a power endurance sport, because unlike running and cycling, where you have a relatively steady power output throughout the Strider or throughout the pedal stroke, we apply in a lot of power very quickly. And then we have sort of a recovery or a glide phase. So similar to running -or excuse me, similar- to rowing in that respect. So we do a fair amount of strength training, which may include plyometrics, it may include med ball slams, Olympic lifts, we actually get propulsion from upper body and core as well. So we’re focused a lot on all the muscle groups of the body and our strength training. But then we work a lot on technique and balance because if you can’t balance on a gliding ski in uncertain terrain all that power you put into it is getting wasted somewhere. So there’s there’s sort of a nuance between training just the aerobic engine and the VO2 max lactate threshold type training that we will do on foot or on skis, or on roller skis, or even on bike. And then the more subtle, sort of neurological neuromuscular training to improve balance and technique. And part of what I love about ski coaching is sort of the art and science of mixing the two, in an ideal scenario you can train both. But at certain points, you’ve got to sort of favor one over the other.

Trevor Connor 1:02:55
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When Should You Train Your Neural Patterns?

Trevor Connor 1:03:48
So the question I have for you.- So this is going to take a second to explain.- But I go back to the biomechanics lab that I worked at, and we were studying the muscle firing patterns and various movements. And when you’re a cyclists, you kind of think, Oh, it’s a quad sport. But actually when you start thinking about all the different smaller stability muscles that are involved in the movement, in a single pedal stroke you’re recruiting 25-30 different muscles over the course of that stroke and add the fire right at the right moments. Same thing with running. Same thing with a lot of these sports. So in something with a higher cadence like cycling or running, training those neural patterns is really key. Otherwise, things start firing at the wrong time or you get inappropriate co-contractions that can really mess up your economy. So my question to you is in those higher,- so I’m already saying those higher cadence sports training that neural site is really important- in those slower sports like rowing or where you have that long glide is training those neural patterns as critical?

Dr. Stephen Seiler 1:05:09
Well, I think there’s a different criticality as a former rower myself. What becomes critical there is the balance issue, what characterizes the great rowers, the great skiers is their weight, their perfect balance, perfect symmetry in the boat. Everything’s in balance, your boat is on the water, not in the water in rowing, in a sense. So you got no balance that’s intrinsic to the boat, your balance is being achieved through your movements and the oars. And so these low cadence workouts for rowers, and for skiers are about achieving powerful pushes and maintaining balance so that the glide phase is optimized. In rowing, we say you win the race between the strokes, because it’s the efficiency of the glide. Are you getting maximum centimeters out of each push, because you have perfect balance. So those push and glide sports, they use a low cadence to work on that, and then if you can’t row well slow, meaning a slow cadence, you won’t row well fast. That’s kind of the mantra of rowing and cross country skiing is you’ve got to have technical mastery at low cadence, and then you transfer it up. Now, for cycling, whether you’re at 70, or 90, or 110 cadence, it’s not harder to sit on the bike, it’s not harder to balance, So it’s a different issue. And then we get over to what you’re talking about, which is the subtleties of firing patterns among these multiple muscles that you’re including the core, the stabilizers versus the drivers, and so forth. And I do think that probably, for example, if you want to be a sprint cyclist, they’ve got to do a lot of high cadence work, because they just have to be able to maximize power through through high cadence and optimize that neuromuscular firing pattern. Now, how much does it matter? How much does the firing pattern change? For a cyclist that started at one year, and then five years later, how much better are they? I don’t know what the data says about that. But I would assume that there are some adaptations that contribute to increased efficiency.

Chris Case 1:07:54
I would also think that in a push and glide sport, since you are relying so much on that glide, that you better work on your techniques, so that you maximize the power with each stroke or push so that you maximize the glide. If that makes sense?

Dr. Stephen Seiler 1:08:15
Yeah, they go together, if I can’t stay in balance, and can’t slide up into what we call the catch, -which is that compressed point where my legs are bent, I’m in a squat position, I’m ready to take the water and pull or push.- Well, yeah, the one leads to the other. So when you’re in good balance, you can pull hard, when you’re able to pull hard, you get nice speed, which gives you a longer glide faze. So there’s a there’s a reciprocal kind of deal. And when everything’s going well, then yeah, you just feel like you just want to keep pulling hard every stroke because the magic is there. But when everything is not going well then the whole cycle feels like crap, you know. So the errors are cyclical in the sense that there is no way to disconnect the problems or the good rowing it’s a pattern, It’s a cycle.

Chris Case 1:09:10

Dr. Stephen Seiler 1:09:10
And these push and glide sports that’s the issue. And that’s when you’ll hear them, Well, I had 10 good strokes today. They strung together 10 strokes in a row, that felt really good. And that was enough to bring them back tomorrow to try again, because it is so darn hard to achieve perfection, like golf, you know? So I think that is a big difference that we see in those sports. When I work with speed skaters they’re so tuned in to that feeling of weight transfer from push to push, and so forth. And those kinds of things I don’t think we talked about as much in cycling.

How Should You Approach The Polarized Training Method?

Chris Case 1:09:50
Let’s move on. I know you guys could talk science all day. But let’s move on from the deeper science and talk somewhat more about the training implications, the characteristics here. And Dr. Siler as a proponent ,almost a popularizer, of the polarized training method, I’m curious to know if based on all the different sports and athletes you’ve looked at, and the research you’ve done over the years, how the polarized training approach works for these different methods, if it’s looks the same, if it works the same, how does that look in practice?

Dr. Stephen Seiler 1:10:32
The heart of the model is that a large percentage of the total volume of training is at the so called low intensity below that first lactate turn point, talking pace, green zone. And we see that in every single sport, so that fundamental anchor is there every time. But then the differentiation will be okay, if 80% of the sessions are low intensity and 20% are threshold plus, then what are those 20% look like. And there you see some variation, you see some longer events where they’ll do more threshold work. And you’ll see the pure the rowing events of the last six minutes and four minute middle distance athletes and so forth, they may do more high intensity work. So the way they’re cutting up the pie of that 20% varies, but they’re still doing the green work, the low intensity volume, they still have the base work that is fundamental to the cyclists, the runner, the swimmer, the rower, and the skier. So that’s what we’ve seen. But then there’s the individualization. And then I guess the other issue is that we are generally seeing that all of the sports, they are careful with how they use the really high intensity work. In a five zone model, the zone five sessions, the really high lactate, you see surprisingly little of that, actually. So you could argue and say, well, I’m going to summarize by saying easy, stays easy, and hard is harder, but actually easy, stays easy. And hard is hard, but not excessively hard. Because excessively hard every day, we’ll also break you down. And that we also see is a typical continuity factor in these different sports. So the basic recipe is surprisingly similar across the sports, but you get tuned in to the subtleties of technique, to the subtleties of local muscle fatigue, running versus cycling. And then maybe we could talk a little bit about whether there’s some training transfer. You know, we go back to that famous term cross training. Yeah, is there such a thing, does it work? So I think I’ll take a pause and let you reflect on what I’ve said already. But I think that’s probably relevant for the listener to is hey, if I do cycling, will that make me a better runner?

Trevor Connor 1:13:34
My first mentor Glen Swan is experienced at a high level of multiple endurance sports, including cycling and skiing. He agrees that the principles are the same, but brings up one other important difference strategy.

Glenn Swan 1:13:47
Well, the principles are the same, we’re talking about using the same motor. So principles are there. And then in some of the other sports, like cross country skiing technique is everything. So you can’t just work on fitness, you’d have to work on technique. Cross country ski racing -I was a good ski racer for a good long time but- there’s not quite so much strategy, there’s pacing, and there are times when it’s desirable to attack or to rest up. But Cycling is an ultimate chess game. There’s so much in cycling that is strategic that it never got old for me. You’ve heard the stories of a pretty small race out in Windsor, New York, at the end of the season. And for a couple of years. I would go out there, I had no teammates necessarily and there’d be these other teams of young guys who are definitely stronger and faster than me. But I would stir the pack up such that they would race against the each other and rip each other’s arms and legs off all day long. Then on the last lap, I would break away with one of those guys, such that their team wouldn’t be chasing. And I’d make sure he did plenty of work and drop him at the end. And at the picnic after the race one year, I overheard these guys saying, how did that old guy beat us? And that’s an ultimate compliment, they couldn’t figure out that he might be old, fat and slow, but he’s smart.

Trevor Connor 1:15:38
So before we get there, I actually do have some questions for you. And actually, there’s something you just brought up don’t make the the hard, too hard. And I have to mention this, I recently had a discussion with a few people on our forum about that high intensity work and brought up the fact that on one of our earlier episodes, you said, even the the pros, -you see when they do that high intensity work.- If they’re doing something around the VT two, they accumulate somewhere in the 35 to 40 minutes of total time at intensity. And the discussion on our forum was somebody did the math on that and said, That’s only like 70-80 TSS and didn’t like it cause that’s not a hard workout. And I was trying to explain but yeah, that’s fine.

Common Misunderstandings About Zones

Dr. Stephen Seiler 1:16:34
Yeah, that’s a sad commentary on the misunderstanding of the TSS, and what it actually measures, which has nothing to do with stress. But that’s fuel for another discussion, We’re measuring load, not stress when we when we start talking about TSS, it’s a TLS. It’s a training load score. The stress is measured a different way, understanding how stressful achieving that load was, it takes different metrics it takes a different approach. So if we can get that across in a different way, then I’m happy to try to help do that. But they are really different. And it’s a sad commentary if people get so wrapped up in the TSS that they train wrong in their effort to achieve some number.

Trevor Connor 1:17:33
No, I agree. And I like to point out to people, I can give you this sprint workout that will have you on the couch the rest of the day, and it registers about 35-40 TSS.

Dr. Stephen Seiler 1:17:46
Yeah, I’ve even had my heart watch- I’ve had 20 millimolar. lactate- and my heart watch told me I didn’t do anything today. You know, it’s just because the algorithms are not perfect. They can’t take into account these really high intensity impacts on muscle. It’s just counting heartbeats, basically.

Trevor Connor 1:18:08
So now the question that I do want to ask you, I’m going to reference a study, I believe you said this was some students of yours who put together this study. So the lead author was Stogwal and looked on a three zone model, how all these different sports broke up their training across the different periods in the season. The one thing that I found interesting was, certainly in rowing and cross country skiing, you saw an extreme polarization, they did almost nothing in zone two. But they did point out that cyclists tended to be a little more pure middle, meaning they did more time- so they still did the bulk of their training in zone one.- But they would do more time in zone two than they would in zone three. And I’ve always wanted to ask you about that. And whether you think that’s the way it should be in cycling, they certainly conclude in the study that they felt cyclists would improve their training if they polarized more than they currently are?But I want to hear your thoughts on this.

Dr. Stephen Seiler 1:19:15
Yeah, that was Thomas Stogwal and Billy Spearly I think Stogwal from austria, and Spearly is based in Germany. So they’re not students of mine, but I know of them and I’ve communicated with them and I think I was even a reviewer on the review they initially did and I challenged them to kind of really push me or push my work and they did and they said look, what about pure middle. So that was an important contribution to help us be more subtle, because they were saying look, things are getting called polarized that aren’t really polarized. You know the training intensity distribution has been called polarized just if it has a lot of low intensity. And so they introduce some more subtlety in the language. And I think that was good now. Yeah, rowing and skiing we also see, when we’ve looked at the data, it’s been very clearly polarized. And I think one of the reasons for that is that in rowing, particularly, you have perfect control of the intensity, you’re on flat water, there’s never hills to climb. They do doubles every day, they don’t do these four hour workouts, they do multiple shorter workouts. 90 minute workouts, and the 90 minutes will be all low intensity, and it’ll just be whoosh, whoosh for 18 strokes a minute for an hour and a half and there’s is no stochasticity. And then they do their annual sessions and they’re very clearly interval session. So yeah, they’re, they’re totally polarized. And then the same with skiiers they’re pretty good at controlling that and they don’t mess around too much in those middle intensities. Then you get to cycling, while the terrain dictates quite a bit of it. And you’ve got a lot of little subtle bumps, there is no such thing as a truly flat road, really, if you look carefully at the GPS. So there’s constant little perturbations in power, and then in a long ride, you get some leakage of the low intensity up, due in part to cardiovascular drift. Also if you’re doing the interval session in the middle of the ride, you get a lot of so called threshold intensity heart rate distribution, just because heart rates either going up through that zone or coming down through that zone. Does that make sense?

Chris Case 1:21:56

Trevor Connor 1:21:57

Dr. Stephen Seiler 1:21:58
So you get a lot of leakage of heart rate, and power up and down through the threshold zone, even though you’re not actually working at threshold. If I do 30 15’s or 30 30s Trevor, you’ve done some of these workouts. If you compare the power profile with the heart rate profile, they don’t match up because you get a by a bipolar power profile and you get a heart rate profile that’s sitting square in the middle.

Trevor Connor 1:22:34
That’s a good point. One of my favorite workouts is the classic tabata and when I’m getting ready to fine tune my form it’s the 20 10s and I’m either at a really high wattage or 100 watts I’m going super easy so if you look at the power it’s super polarized, but my heart rate the whole workout is sitting right in the middle of that zone two or top end of that zone two.

Dr. Stephen Seiler 1:23:00
Yeah, yeah. So now how do you categorize that workout right? So this is where we get into some issues, the weeds get kind of thick in cycling because of the tendency towards the longer workouts with a bit of a mixed intensity profile where we add some so called efforts during the ride Yeah, the paints are going to mix, the colors are going to mix. and so green plus red equals yellow or purple really, but you know, it ends up being kind of in between on the intensity scale and the intensity distribution. So I do think that’s one of the reasons It looks like you’re doing a lot of threshold work that you may actually not be doing or at least not intentionally.

Trevor Connor 1:23:48
I’m glad to hear you say that because I felt the same way. We actually did a video that’s up on our website where we addressed this and I said exactly the same thing. Which is you’re not seeing these athletes doing a ton of intentional threshold work so in that zone two, it’s just leakage. It’s going up into the lower end of that zone when they’re trying to do zone one work or dropping down a little bit when they’re trying to do their high intensity

Dr. Stephen Seiler 1:24:16
Yeah and let’s say my daughter does -she’s running but at the same would be in cycling with me. -If I do say a five times eight minute session and I pace it right then those first couple of eight minutes are going to kind of be zone three and then I’m gonna glide in zone four throughout the session, you know I mean, there’s kind of a upward drift. So even though I hold power, constant, heart rate is going up so it’s not stable in zone three or zone four, it kind of probably is upper zone three at the start and upper four at the end. And I’m happy with that workout, If I held power right? So then you’re gonna say, well, then you were quite a bit at your threshold. Well, actually, No, I didn’t I was at zone for power the whole way. But I’m 55 and takes my heart rate a while to get really rockin. So I have to account for that, and I have to pace it. So that’s one issue. The other issue is that, hey, you know there is nothing wrong with a threshold session. And that may seem like that Stephen Seiler is saying it’s threshold sessions are toxic. No, I’m not saying that. But what I am saying is that threshold sessions are hard sessions, and they need to be treated as such, the accounting system needs to treat them that way. And probably if you’re going to do a threshold session, then do it, and extend. Because usually, the limiting issue on these thresholds is not the intensity, it’s the duration you can hold. And so if people want to do tough threshold sessions, then get into your threshold, but then do more work there. And then it’s going to be a tough session. And it needs to be in the accounting scene as a high-intensity, high-stress session with appropriate recovery time thereafter.

How To Add Volume In Different Sports?

Trevor Connor 1:26:27
So getting back to comparing the training in these different sports, you’ve definitely demonstrated that they all polarize. But it does seem there is one thing that is very different, is how volume is added. And that seems to be where Cycling is a bit of a unique sport, because all the other sports do it by frequency of workouts.

Dr. Stephen Seiler 1:26:51
Yeah, or you might so what happens is, it’s almost like cellular proliferation First, the cells get bigger, and then they split. So first, the workouts get longer, but then they reach some critical length. And then they start splitting up and say, well now i’m going to start doing two workouts and for runners, that’s probably somewhere between 60 and 80 minutes, maybe 90, but they’re not going to do two hour easy runs. That’s a once a week kind of thing. So yeah, so that’s the same with rowing, you don’t see too many rowers doing two hour rows, they’re doing 80 minute rows, 60 minute rows, but they’re doing two of them. So they’re getting three hours of work. But the younger athletes will do once a day. And then as they get older, we’re lengthening their workouts. They’re going from eight kilometers to 10 to 12 to 14. And then we reach some point where we say all right, Bjorn, you’ve reached the point where I think we’re going to do two workouts a week or two days a week you’re going to do doubles, Are you ready? Yes, I’m ready. So that’s the transition, It’s first lengthen, lengthen, lengthen, and then split. Cycling doesn’t do the split. It just gets longer. But I think we’re seeing some of that split now.

Trevor Connor 1:28:25
Do you think that’s a good thing? Do you think that this is something other sports have figured out that cycling’s behind the little behind on?

Dr. Stephen Seiler 1:28:33
I mean, I do think it’s a bit a bit of Winnie the Pooh both wanting to have my cake and eat it too that probably there is utility in both. We’re actually gearing up, I’ve got a application in the European Union for a big study looking at precisely this. Comparing long four hour rides with two times two hour and actually doing a three week intervention and trying to see if we can tease apart stress responses and adaptive responses to the two different approaches. It’s a tough study to achieve, to find enough cyclists that can and are willing to do this kind of thing but I think that’s where we’ve got to go, we’ve got to look at not only the adaptations but also the stress responses and see how the balance is being shifted by these two approaches. In the literature, there’s hints in both directions that -Yeah, like you, I know you’re a fan of the long sessions. I’ve listened to the podcast about the longer vs. a two time short, I think it was really good and – it goes into those weeds and the pluses and minuses of the two because the longer sessions in that workout you amplify some adaptive signals, probably with glycogen depletion, and so forth. Whereas with the two times two type scenario, you create maybe a longer window of responsiveness. So boy the jury’s out. I don’t think there’s a clear answer, and probably we’re not going to end up -even with some more research, -we’re probably not going to end up saying, nope, cyclists have just been stupid. You know, it was two times two all you know, it was doubles all along. I don’t think that’s what we’ll find, we’ll find that probably that judicious use of both is a good way to go. Meaning the cyclist is going to need some needs some long rides, when they race long.

Trevor Connor 1:30:40
And Chris has given me this look of the jury’s still out on cyclists. But Trevor, you’ve definitely been stupid.

Dr. Stephen Seiler 1:30:48
Well, I’m gonna be honest with you guys. And again, I’m the sport scientists, I make a living trying to pretend like I’m supposed to be really smart on this stuff. But good grief, coaches and athletes have been experimenting on this for decades. So I don’t think they’re stupid, I don’t think they’ve missed out and we never thought of two times two, you know, we never thought of doing doubles. Of course they have. So, we just have to accept that one of the big issues is that the cycling does have some long races, and a lot of downtime. And so part of that is you got to prepare for that. But I do think that with what we’re seeing, and with more cross communication between the different sports, that we’re seeing some fertilization, some new ideas, and we’re seeing some of our best cyclists are saying, Hey, you know what, I can do doubles, this can be a good approach. Especially with the advent of these virtual methodologies, where it makes it less boring, there’s a lot of different things that are coming together. Right? And so I think that’s why we’re starting to see a little bit more flexibility up in the heads of some of our cyclists. So that’s a good thing. But I don’t think in five years I’ll be able to come back to you say, well, we have the answer. You know, t’s complex and the degree of overlapping, the degree of individualization, the degree of interaction with nutrition and genetics and so forth, is going to be so significant that it I don’t think we’ll see a black and white deal it’ll be gray.

The Importance Of Cross-Training

Trevor Connor 1:32:42
The last thing we’ll discuss is how well training and one endurance sports transfers to the others. But before we get into it with Dr. Seiler, let’s hear Joe Gambles take on the question.

Joe Gambles 1:32:51
Swimmers, or triathletes, because triathletes swimmers all swim with a watch which I shake my head at. But swimmers will use a pace clock. And it’s really interesting how swimmers train because you’ll never see a swimmer do what something like a cyclist would do. Maybe they might do three by 20 minutes in a two-hour ride, they’ll break it into tiny, bite-sized pieces, they’ll do 80 times 50 on a tight interval, because I think it’s engaging, you can’t just go and swim,- or some people can -you can’t go and swim three by 20 minutes and hold pace. But they figured out that the body doesn’t really realize that I’ve stopped for five seconds, and they can actually- it’s like tabata like they can swim at a higher rate with a five-second or 10-second rest and still get the same amount of volume without going okay, we’re just gonna do an hour as hard as we can. Because especially with swimming being such a technical sport, you can’t focus for an hour straight on really good technique. But if you break it into bite sized pieces, 50’s or 100’s you can actually really focus on the real technical aspects of the swim which is crucial. If you don’t have a good technique in swimming, you’re not going anywhere. So I think that’s a really great way that they’ve sort of managed to still build a bigger aerobic capacity but break it down. And I think like even someone, I’m guessing you know, who Arthur lydiard is, he actually used to do this with his runners. He’d do fartleks where a lot of speed play, they would still do a lot of volume but he would break it into these small pieces that were achievable and mentally they really kept the athletes I think fresh. It sort of tricked them into still running 100 miles a week but you know in a different way, he attacked it from different angles, which is really interesting.

Chris Case 1:34:59
Let me hit you with a final question here, Dr. Seiler. And that is how do these various sports transfer over in terms of training from one to the other? Big question.

Dr. Stephen Seiler 1:35:13
It’s a tough one too. But there’s been some research and we can make some decently educated guesses. Swimming probably doesn’t transfer too much of anything else, besides swimming. I’m going to be really rough on that one. In other words, probably the triathlete doesn’t get faster in running from their swimming work. But it does look like the cycling modality and the running modality, there’s some degree of interplay, some trends for some crossover. Particularly, I would say, for runners, I think that adding some cycling can be a good solution because it adds training volume, it adds peripheral muscle stimulation ,without adding that low eccentric muscular ballistic loading. And for a lot of runners that are injury prone, that are on the ragged edge there, that is a way for them to train more without getting more frequently injured. So I do see some benefits there for athletes that are not just kind of born to run with a body that doesn’t get injured, they weigh 56 kilos and all this stuff. And plus, we got to face it, the Olympic distance triathlete’s we’re seeing that they are not running huge volumes, but they’re running pretty darn fast 10k’s suggesting that they’re not wasting their time. You know, the cycling is not totally independent, and they’re getting some transfer. If I look, -you got to be-if you want to win a Olympic triathlon, you got to be a 28, mid 28 minute 10k runner, you’re a solid 10k runner. And you’re doing that on maybe 100 kilometers a week, you’re not doing a huge volume compared to a specialist. So it looks like they’re getting some transfer.

Trevor Connor 1:37:17
The other thing that’s interesting- this I read in a really good review from Dr. Isaran, is -that while we talk about the specificity of training, the overtraining and potential for injury is also actually somewhat specific. So he talks about the fact that you can increase the load of total training, while reducing the risk of overtraining and injury by doing some cross-training, which I found really interesting.

Dr. Stephen Seiler 1:37:56
Oh, yeah, absolutely that fits right in. For runners, most of the injuries are below the knee so that’s where they’re most vulnerable. If they’re the good distance runners, they’re getting various issues with their shins with their plantar fascia with their achilles, with their knees, and so forth. You know, there can be some stuff up in the hips, but predominantly, they’re below the knee injuries. If you take the rowers they’re having trouble with their back, their low back, and then they get stress fractures in their ribs, the swimmers they get shoulder problems. So most of the sports have a kind of an achilles area to use a term, and then you’re working around that. The rowers can use cycling as an additional stimulate, the speed skaters use cycling a lot because the loading on the legs in speed skating every time they go around the curve is just so high, that they can handle more than about three days in a row of tough speed skating, and then they unload on the bike. So these are different ways to train the body without overloading those weak links or those pressure points you might say in that movement.

Trevor Connor 1:39:18
I trained at the same center as the Canadian National Rowing team, and this was the team that won the gold and the heavy eight. And I was surprised how frequently they came out and went on our base mile training rides on the bike.

Dr. Stephen Seiler 1:39:32
Yeah, So again, that’s one of the issues with rowing. When you’re down at that stroke rate I was talking about, 18-20 you’re pulling pretty damn hard. So there’s a pretty heavy muscular load and particularly on the musculature in the low back, and then the ribs actually get tugged on every stroke and then you get stress fractures in the ribs because these oar blades are so wide now so they hook into the water so firmly that the load of the resistance is really high at the beginning of what we call the catch. So every sport has these- even within the stroke or the stride or whatever- vulnerabilities and then that’s where maybe cross-training can help to kind of keep things at bay, while maintaining some cardiovascular load some general muscular stimulation and so forth.

Chris Case 1:40:33
I would assume though, if your primary sport was running, you would probably want to do your interval sessions on the track and maybe some of your slow days of running, you would increasingly substitute in some cycling to reduce stress, right?

Dr. Stephen Seiler 1:40:58
Yeah, so let’s say we’ve got a female athlete, we’ve got one in Norway, she’s had some injury issues, she started doing two a days, two running sessions a day. She started switching out one of those running sessions with different kinds of cross-training with elliptical, with the stair-step, with the cycling and so forth, she was a skier before, so she did some roller skiing. So she reduced her total volume of running, but maintain the total volume of training. And then as you say, her specific hard sessions were running, that was just a subtle switch she made she said, Look, I stay healthier, if I bring down my total running kilometers per week, but I maintain my total volume by substituting in these other modalities and she stays happy, stays healthy, and runs better. You know I think cyclists can do that, too. Cyclist can get into this where you’re always in that crouch position, you need to extend you need to do some counter activities that kind of put you in a different body position that stretch you back out, I think also they need bone stimulation. So like the team, I work with the coach, he has his athletes at least run once a week, and this is a professional cycling team but he wants him to get some stimulation for bone health it’s also just a mental break. It’s just an alternative modality they can put on their headphones and go run for 45 minutes, and it’s good for them.

What Is The Right Way To Build Intensity In Intervals?

Trevor Connor 1:42:38
So we’re going on a bit of a tangent here. But while we have you on the show, I actually really want to ask you this question because I think the debate that I’ve seen most frequently on our forum and through emails, is when somebody is doing your four-by-eight-minute intervals, what’s the intensity? And if we get into the weeds, is it 101% or 100%? You know, my opinion, which is that really doesn’t matter because day to day fluctuation. but should you be targeting a number? Or should you just be doing them as hard as you can do them?

Dr. Stephen Seiler 1:43:16
Yeah, if I were going to give someone advice on that, I’d say all right, if you’re gonna do four by eight let’s go ahead and plan on doing it for four weeks. Let’s go ahead and put in a block or a cycle, a four-week cycle where every week for four weeks, we’re going to do a four by eight-session, just one, and then what you do, you may have a second hard day that you do a race or you do whatever. But we’re going to have one session, and we’re going to start that first week totally on feel in week one, that’s what I would. I would say just Yeah, you’re looking at your power, you’re looking at your heart rate, but just try to find what feels uncomfortably comfortable. (Or comfortably uncomfortable.) You can decide which way you want it. It should feel like Alright, this is tough, but I’m in the zone I can hold. And each bout feels tougher, but you try for even pacing, but just go on feel and then you get some numbers. You say okay, I held 350 watts. Alright, so now you got a benchmark. And now you can start saying alright, what was my heart rate, and then you can go in week two, you’re going to try to add five watts or maybe 10, but not more. Or you could say I’m going to add an extra interval an extra bout. So you could start at three times eight in week one, and then go to four times eight in week two at the same power and go to five times eight in week three at the same power and then week four is your unload. Or maybe you do three times eight at a to slightly higher power. You with me? So what I would try to get listeners to think about, is thinking of it as a staircase approach. A set of stairs has a rise and run, it lifts up and then it goes forward. And so you want to use the run, you want to extend also, when you’re doing intervals. And so that’s a tool in your toolbox is, plan a four week cycle start with three times eight minutes on feel. And then based on what you’ve achieved in week one,- so let’s say it was 350 or 300 watts or whatever.- Now say, Alright, I’m gonna do one more of those. So now the workouts four times eight. And then if that goes and probably your heart rate drifted up even farther, you were even farther on the edge of what felt like you can do, but you did it. So now we’re going to say week three, I’m going for five of these bad boys, five times eight. So now I have extended, extended, extended, and then if I achieve that, now I’m up at 40 minutes of total work. Now I’m going to add 10 watts and go back down to three repeats for my next cycle. I’m going to try to peak at the end of that four weeks with a three times eight at a higher wattage than I have achieved before.

Trevor Connor 1:46:26
I love the fact that you started by saying go with the feel, you’re going for a particular feel. Because I do think, particularly in this type of work, it’s important that you have the sense for the field and don’t just say, here’s my number, I’m going to lock in that number. And whether I’m dying or breathing through my nose, I don’t care because it’s the right number.

Dr. Stephen Seiler 1:46:48
There’s so much day-to-day variation. And just in large parts of the season, I think feel is the appropriate tool. And then as you’re gearing up for a race, or you’re trying to peak then yeah, you can be a bit more external load focused and try to zero in on a specific pace. But I think that interplay, a lot of top coaches I talked to and listen to and read about they try to carefully manage the use of feel versus hard numbers. And they do both. But they try to find the right balance because psychologically those hard number type workouts where you’re just saying, Well, if I don’t hold 350 for all four of these then it’s a failure. Man, that is just psychologically damaging and it’s not really consistent with the realities of day-to-day variation.

Today’s Take-Homes

Chris Case 1:47:42
Dr. Seiler, you know how this goes a very long discussion today a lot that we’ve unpacked and a lot more we could have unpacked. What would you say are the greatest, most important take-homes, somebody should take from this discussion today. We will start with you.

Dr. Stephen Seiler 1:48:00
Well, all heart rate is not the same. So that’s the first thing is if you’re switching from cycling to running, then heart rate is going to feel too high. If you’re going from running to cycling, then heart rates gonna feel too low, given the amount of pain you’re feeling, but it’s okay don’t get frustrated, it’ll get better. That’s just because it’s specific. So heart rates not the same that would be take-home message number one, and maybe the most practical element of it. And then I guess down at that muscular level, be aware of these difference of the rhythms of the musculature and then how you can use if it. If you’re a push and glide athlete, then you’re going to use that for gearing, if you’re a runner or a cyclist, then you’re not going to have that same push and glide feeling. And you’re not going to use cadence, in the same way, it’s going to be more force than you’re modulating. And you just have to be aware of that difference if you start moving across the sports. Then maybe the third take-home would be, don’t be afraid to try -if you’re having some injury issues or some staleness issues – don’t be afraid to try switching out some workouts and going and using an alternative modality because a lot of times that can turn out to be a good thing and it can freshen up your mentality and also freshen up your legs or your body. So I do think we get scared to do something different from our specific sport. But I think a little bit of variation and cross-training is probably pretty healthy and almost rejuvenating for a lot of athletes.

Chris Case 1:49:00
My take-home is going to dovetail with what you’ve just said because I’ve started to do a little bit more running. It used to be my primary sport long ago, and then I became a cyclist. But now I’m getting back into running more. And it certainly is I think more important for me mentally than anything. Physically, I hope that it is actually transferring over I think the bone density issue is important as well so that’s good. But more important to me I think is the fresh approach that it offers in that break from the cycling. So I would encourage people -I know, it’s funny, we talked about how evolutionarily, humans are basically meant to be upright and running the most- And then we talked about how many injuries there are in runners, we talked about how hard it is on the muscles, how much recovery you need. And I think we speak to a lot of cyclists on this show and I think a lot of cyclists really don’t like running. But if you get into the habit of doing it, and you get past that nasty phase at the start, and you just maintain a little bit, I think it actually is a really pleasurable thing to do and it has its benefits. So that’s what I would.

Dr. Stephen Seiler 1:51:10
If I can jump in here on that is we weren’t evolutionarily designed to run on asphalt and cement.

Chris Case 1:51:17
Well there you go. Correct.

Dr. Stephen Seiler 1:51:19
So, that is a key caveat. So to the cyclists, one of the best things to help them in that transition is stay off the asphalt, find dirt trails, find soft ground, find golf courses, find grass, and that will help.

Chris Case 1:51:35
Yeah, and that’s the type of running idea. It’s never on roads, it’s always on trails and things so yep. Trevor?

Trevor Connor 1:51:43
I gonna have to think about this, because I really haven’t gotten past my big take home, which is a good way to finally pronounce symmorphosis.

Chris Case 1:51:52
Hey, that’s something.

Trevor Connor 1:51:54
That just made my day because that has been a beast on my back for a long time. So I’ll just make mine really simple, which is, we definitely want to talk about these other sports and you know, we always talk about the specificity so you can start to think that oh, the training is very different between all these endurance sports. But I think when you get into the details, yes, when you’re talking about the principles, when you’re talking about the broad strokes, it’s actually quite remarkable how much all these sports have really landed on the same overall approach the same way to train to get to your best endurance performance.

Chris Case 1:52:36
Doctor Seiler always a pleasure. Thank you again for joining us.

Dr. Stephen Seiler 1:52:40
Yeah, I enjoyed it. And I hope the readers or the viewers enjoy it because I think it was a different topic and I think that’s good. And I do think that just bringing down the barrier for a bit of cross-training, cross-fertilization, whatever you want to call it. I think that’s a good thing.

Chris Case 1:53:03
That was another episode of Fast Talk. Subscribe to Fast Talk wherever you prefer to find your favorite podcast. Be sure to leave us a rating and a review. The thoughts and opinions expressed on Fast Talk are those of the individual. As always, we’d love your feedback. Join the conversation at to discuss each and every episode and become a member of Fast Talk Laboratories at to become a part of our education and coaching community. For Dr. Stephen Seiler, Adam St. Pierre, Joe Gambles, Glenn Swan and Trevor Connor. I’m Chris Case. Thanks for listening.