Muscular Endurance Training

Martin: I think most, uh, runners, trail, trail runners especially, I mean, they don’t realize that you will hike a lot of the big part of the, of the distance. And so you think hiking will be easy. I, I will just train running. So this is, I think, a big mistake that the trail runners make, especially ultra.

Steve: If you’re enjoying the show and want to take the next step in your training. Join our newsletter and receive a free 4-week sample training plan. Head on over to uphillathlete.com/letsgo. And once you sign up, you’ll instantly get a link to try out some of our most popular training plans. It’s a great way to get a feel for how we train our athletes for big mountain goals. Check it out at uphillathlete.com/letsgo. That’s upillathlete.com/letsgo.

Steve: You’ve put in the miles, you’ve built the aerobic base, and you can go all day at a moderate pace. But somewhere above a certain intensity, maybe on a steep uphill or on a technical climb on a trail or at an altitude of an 8,000-meter peak, your legs just simply give out before your lungs do. You’re not out of breath, you’re just kinda done. That feeling has a name, and more importantly, it has a fix. My name is Steve House, and welcome to the Uphill Athlete Podcast. With me today are two of the Uphill Athlete coaches who I’ve worked with extensively. Have both applied muscular endurance training with mountaineers, ultra-runners, and ski athletes, with athletes just starting out, as well as people racing at the higher- highest level.

So let’s get into it. Martin, you’re based in Chamonix. You’ve got a sports science degree. You’re working on one more, and you’ve done an FKT on Aconcagua, summiting from base camp in three hours and 38 minutes. Give me a quick 30-second version of what keeps you back to high-altitude performance specifically, and what it is or the mountains that keep just pulling you back from a scientific point of view.

Martin: I think, um, it’s a curiosity and, uh, I like challenges. Alway- always have. I started with endurance sports when I was a kid. Uh, always loved, uh, running around my home village, but then eventually started running competitions, middle distance running, but also dreamt, always dreamt about mountains. And I think what draws me to the mountains is the vertical aspect, the views, just the awesomeness of the mountains and the environment.

But I think also it’s about how challenging it is. So walking uphill, hiking uphill is, is, is hard. I think many– most people can agree with that. and I just really, I just really love it, the challenge of it, and, uh, whenever I see a hill, I kind of wanna run it. So that’s basically led me to run and try to kinda run Aconcagua.

Uh, so, uh, managed to break the record back then, and, um, that inspired me to go higher, so made it even to eight thousand meters, which was my dream since I was a kid. And I think that’s, that’s where it gets more challenging with, um, the altitude, the effects of it, and, um… But yeah, I’m always inspired by that, and I’ve been training for it up to today.

The science of it also, of course, then, yeah, the science, the really look– kind of looking into the, the performance, the physiology, what is behind it, how especially the altitude affects our, the performance. So, um, yeah, I’m, I’m really, really excited about that too.

Steve: Ben Morley is joining us, and he’s been coaching since two thousand and seven with a deep background in Nordic skiing. Ben’s philosophy and approach is really grounded in long-term athletic development and durability, and philosophy that’s partially informed by one of his own backcountry skiing injuries. Ben, really glad to have you. What– How– Your co– As your coaching philosophy sort of centers on durability and long-term development, what do you mean by durability before we get into the topic of muscular endurance?

Ben: Yeah. So thanks, thanks Steve, and good to be with you guys today. Um, durability stems from, you know, basically, I think putting in all the, all the foundational work too first before you get into the really specific kind of training as well. So, you know, we can’t really skip the steps of jumping into zone three work right away, jumping into muscular endurance zone three work.

It, it really has to start from the beginning of doing the base strength phases, uh, during the essential, you know, zone one, zone two workouts and building up that, that frame for months on end before we even think about jumping into, um, you know, higher intensity strength and then building towards, uh, muscular endurance stuff in the gym and then muscular endurance stuff outdoors up steep hills with heavy packs.

So, you know, it’s a long progression. Durability means a lot of different things, right? And we need to work all our different systems and be well adapted, um, you know, from strength to aerobic to anaerobic before we can get that specific, uh, necessary muscular endurance workout where we’re carrying that heavy pack for thirty-five, forty-five minutes really hard.

So it’s not any one thing, it’s the whole gamut of what we work on, uh, with athletes here at Uphill Athlete.

Steve: Yeah. And durability has been a, a topic of, uh, kind of a buzzword or in the coaching circles lately. I know a lot of people are talking about it, and we’re gonna talk about it more in a- another time. Martin, let’s start with some definitions. What is muscular endurance and what is– Can you help us understand the difference between local fatigue and global fatigue?

‘Cause I think that distinction between local and global fatigue is really at the heart of everything we’re gonna talk about.

Martin: Yeah. So what is muscular endurance? Um, by definition, it stands somewhere between the strength and endurance. Uh, it is a capacity, uh, in endurance athletes, at least. It’s a sport-specific capacity, uh, to, uh, resist fatigue and, uh, produce a submaximal force, uh, keep coordination, keep the economy, uh, over, let’s say, prolonged duration or prolonged effort and repeated, uh, contractions of the muscles.

Um, so that it– that would be the definition. And then, um, when it comes to local and, uh, central, uh, central fatigue. So, uh, basically, muscular endurance is the, in the category of local, uh, local, uh, fatigue or local muscular endurance, we can call it. Um, so what is the difference there? So when we– uh, the body is trying to respond to the demand of the exercise.

Uh, so let’s take an example of walking uphill, uh, going up a mountain, running up a mountain. Uh, so the, the whole physiology response, uh, the central, uh, what we call central is really anything from, uh, cardio, respiratory function, vascular. So basically, it’s about distribution primarily of oxygen to the tissues, but primarily actually the muscles.

They have a high demand for oxygen to, um, provide the aerobic metabolism with oxygen. So then the metabolism can actually, uh, produce energy for the muscles to do the work. So, um, that is the central part, really the, the transport, the distribution of oxygen, but also the nutrients through the bloodstream to the working muscles.

So basically, that’s the first part of the equation, and the second part is then the muscles. What happens in the muscles? And so, um- What we want to discuss today is actually what will– what is the limiter at any given time during the exercise? Uh, and, um, and yeah, so, uh, the muscle endurance specifically talks about when it becomes the limiter and how we can train it.

Steve: Yeah. And we’ve written and talked about local muscular endurance for many years at Uphill Athlete, and it really is that idea like walking uphill, the legs and the glutes are the local musc- muscles that are the limiter at a high strength, high endurance activity like carrying a heavy pack uphill. Ben, let’s kind of look at this through the lens of, um, skiing. I mean, could be almost any kind of skiing, ski, skimo, ski, ski touring, Nordic skiing. How do you describe this ME concept to skiers, uh, who like to think that they’re already fit? How do you get this across?

Ben: Yeah. Well, I mean, it’s, it’s much different, right? Like, um, you might have somebody that’s in, in pretty good shape, uh, that can You know, run two plus hours really easy, or they could go on a, a moderate ski tour, uh, two, three plus hours. Or a cross-country skier could be cruising along on varied terrain and, and really tap into their aerobic system and feel pretty solid, right?

But when we get into steeper terrain, heavier weight, um, you know, and, and thinking about like even cross-country skiing, where you have to double pole for hours on end, you’re, you’re working a completely different system, right? And we have to train that. So for, for cross-country skiers, it’s like we will go out and just do, you know, sometimes a two-hour straight double pole.

And it’s– You’re definitely getting some aerobic work in, but, you know, you find it’s, it’s harder to get your heart rate up as much, right? Um, but that’s because we’re, we’re trying to really focus on that, that muscular endurance aspect of the upper body that’s so key in cross-country skiing. So, it could be the same kind of work that you’re doing in schema, where we gradually start to work in steeper terrain, add a little bit more weight, but have that workou- workout be specifically focused on building that kind of system, right?

Um, so yeah, you can be in great shape, but I’ve seen it time and time again of like cross-country skiers that are in fantastic shape, right? And then the double poling is the limiting factor. Um, so yeah, there, there’s definitely a difference there.

Steve: Where– what is the injury prevention angle for doing muscular endurance? Specifically, like, kinda what happens when some of these slow twitch muscles that help stabilize joints get tired? What happens to movement quality and injury risk?

Ben: Yeah, I mean, movement quality goes down, injury, injury goes up, right? So, um, and like I, I spoke to this before, you can’t jump straight into the muscular endurance. It’s the, the base strength work is going to support that muscular endurance work. So it’s the core stability work that you put in prior to jumping into this muscular endurance stuff that allows you to have that correct body position and move efficiently and effectively. Um, so it’s– like I said, again, we can’t just jump straight into ME work and go hard. Um, it’s the injury prevention work that goes into base strength before that

Steve: Yeah. Makes sense. And, like you said, it has to progress, right? Like, it has to– the sandcastle has to be built in the right order. You can’t just put… You can’t do things in the wrong order or– and expect to get good results. If someone is able to run, say, 50 miles a week, pretty decent volume, and they feel like they’re aerobically fit, what would be a good test for them to understand that muscular endurance may actually be their limiter? How would, how would you prescribe a, a, a test to someone?

Ben: Yeah. I mean, we, we do this, um, you know, at Uphill Athlete too when we’re, when we’re coaching. But something like an anaerobic threshold test where you’re running uphill, like just really hard, as hard as you can go. I mean, this can be anywhere between thirty, forty-five minutes, right? And often you will find if it’s steep enough, um, your, your heart rate might not be able to get up there quite as well, as easily if, uh, you know, your muscular endurance isn’t solid, if your legs aren’t solid.

So that’s– that can be a good test to kind of figure out where you’re at, um, I would say. And then, you know, we look at that data, and then we decide, okay, what kind of training do we need to do to get to the point where we wanna be, um, to be able to get that heart rate up with pushing some weight as well?

Martin: If I can add to the 50, the, the running. I, I think that, uh, we should always keep in mind that it’s sport-specific or within the runners, uh, for running especially when, uh, for half marathon, marathon running also. I think there is that aspect of muscle endurance. It’s actually the capacity of the athletes to sustain so many– so much impact.

So actually, they are not so limited by the cardiovascular function per se. It’s actually to be able to go so fast at such a high speed for so m-so much time. So, uh, so the, the, the muscle strength work is, is so, so important. So I think it’s, it’s, you know, it’s, it’s in, in its own category within running.

But I think for trail running, mountain sports, it’s, that’s, it’s, that’s our domain. Um, I think, uh, the way at least I address it for my athletes in trail running, in ultras is, um, it– and it’s tied to the durability, right? So one thing is to run for one, two hours, but what happens after four, five, six hours or twenty hours running those really long ultras?

So I think then the muscle endurance is really a strong factor. It’s actually you’re not limited by card- by your central function so much anymore. You’re so tired, but actually being able to keep going, just hiking takes so, so much effort. So then I think then the training, then muscle endurance is a key.

And I would say also defin- differently for uphill, def- differently for the demands of the downhill, right? So it, uh, it’s always, uh, worth to analyze the sport, to, to, to look at the profile of the e-trace and, uh, take it from there.

Steve: Yeah. Yeah, I think that the fingerprint of a muscular endurance deficit is always that the legs fail before the lungs. And I’ve seen this in, just as an observer, like at Hardrock before, you know, it’s like, it’s– there’s a– you can tell who can run the hills and who’s walking all the hills, and obviously over 100 miles or more, that takes– that makes a big difference in time. So, um, Martin, you wanna just walk us through what’s happening inside a muscle during this kind of sustained high-force output? Why does it fall apart? What does, what does muscular endurance training structurally change?

Martin: Yeah. So as we all said, Ben, Ben highlighted this, that it’s all on the top of the base strength, right? So, uh, it’s about the muscles, muscle fibers. So they should, by this point, when you go into the stage of training of muscle endurance, they should be really strong. You, you should really increase your maximum strength capacity.

So then whatever you do, whatever those muscles are required to do is, uh, at a kind of a lower percentage of the maximum. Uh, that’s one part. But then when we look into the muscle, so we, uh, we have different types of, uh, muscle fibers, so slow twitch and then fast twitch. And there are also the subcategories of this fast-twitch.

Uh, I think, uh, this, this is, uh, quite, um, known for all endurance athletes, but just to be clear, uh, slow-twitch fibers, uh, they have low force, but they, they have high endurance, high capacity go– to go for a very long time. Uh, but then– and then vice versa, the fast-twitch fibers, they can produce a lot of force, a lot of power, uh, but they don’t last very long.

And then there’s that subcategory of type IIa, uh, versus, uh, IIx. So those are really powerful but very short, uh, short-lasting. Uh, so those between… So basically with, uh, chronic long-term endurance training, we’ve observed that, or scientists have observed that some of these fast-twitch fibers can actually transform into slow-twitch fibers, which is, for endurance athletes, at least beneficial.

It’s at a cost of losing power, losing that absolute sprinting speed, but that’s not really a factor for most endurance athletes. We want to be able to go for very long time. And so then, uh, that would be kind of the first thing to really target the slow-twitch muscle fibers and make them really robust, really strong, really resistant to fatigue.

So what does that mean? So I would say, you know, with, with– I, I would keep it in like different categories. So metabolism. Metabolism, so what is happening in those muscle fibers. Uh, so the, um, uh, one important part also to mention, and that actually links the central, central factor distributing the blood to those muscle fibers, so capillarization.

I think we can agree that this is really huge and also, uh, one of the key adaptations from mus- specifically muscle endurance, uh, endurance training. So you can really be efficient distributing blood, oxygen, and m- and metabolites and also, uh, getting, getting those metabolites result of the metabolism out of there, uh, quickly and efficiently Uh, and then the metabolism, so basically producing the energy for, for the, for the work that the muscles do.

So we are targeting all of it. We’re, we’re making those fibers really, uh, really strong, uh, being able to stay in, uh, fat metabolism, which is the one that we want. That’s the long-term, efficient, oxygen-dependent one. Uh, and we want to postpone the shift or kind of turn into the, uh, the glycolysis.

So that’s– it, it’s, it’s a factor. It’s, it’s of course something that is happening naturally, but it comes at a cost, and we want to postpone that, the gly- the glycolysis, the lactate production, uh, and other metabolites, the acr- increase in acidity, because that in turn will make everything more difficult, more complicated.

The contractility of the fibers will go down. So yeah, it’s, it’s very much the, the metabolism, uh, part of the, of the s- the picture. Uh, also in terms of neuromuscular connections, so, uh, we’re, we’re trying to, um, make sure that the muscle fibers are still recruited, uh, the– they are well-coordinated, so the, the movements are really efficient.

And as we discussed with the fatigue, this is starting to fall apart. The, the movements are becoming, uh, less efficient, uh, the form goes down, and, uh, basically, uh, we-we’re starting to feel it. The fatigue will show up one way or the other. Um, then the mechanically, as I mentioned, so being able to perform those contractions or those movements going up the hill, uh, from like the really high ceiling, so the maximum strength.

We want to really have that strong max, uh, max strength stage before, um, resistance to damage. So I think, uh, this links to the types of constructions really important to– So I think most of our Up- Uphill Athlete programs for muscle endurance include both the concentric and the eccentric movements. So concentric for me is most important for the uphill, uh, eccentric especially for the downhill.

Of course, there’s always a combination of all, all of those, but with the, with the eccentric contractions, what is the deal is that it create– can create a lot of damage Real damage that the, the muscle fibers are actually kind of torn. Uh, the fascia is, is damaged, and so, of course, that creates, uh, inflammation and, uh, and pain.

And, uh, of course, uh, overall the, the performance will suffer, especially when the, the athlete has to go– keep going, and it– this is actually happening during that, that one activity or during that one race, for example. But, uh, the good news is that this, this capacity is, is, uh, trainable, uh, pretty easily. Um, but I think it’s re-really good to, to think about it and, uh, distinguish.

Um, yeah, and I think then the biomechanics, so as we discussed, it’s also not, not just about the primary movers, the big muscle groups that are doing the movement. It’s also about the movement, the, um, the muscles that are stabilizers. So if they do the work, if they have that fatigue resistance and muscle endurance, then the big mo– primary movers, they can do their job.

But usually, what happens when the stabilizers start to kind of fade, the big muscles try to catch up. They try to kind of, uh, do the work of the stabilizers, uh, but that’s not their job, and then everything goes down. Everything starts to crumble, and, uh, we just feel the fatigue. Also back to the injuries, uh, uh, over the extended periods of time, uh, this can, uh, definitely lead to some overuse injuries too.

Steve: Yeah, I think it’s one of the, one of the things that helps people get on board with muscular endurance training is that when the, your legs, the local muscular, muscles, in this case of going uphill, the legs can… are strong enough in this way, they can finally push the cardiovascular system to its actual limit, and you can get the most out of the input, which is the, the, the breathing and the blood flow and the, and the glycogen that you’re delivering, um, and, and the nutrients you’re delivering, the metabolites, as you said. So let’s, let’s shift over to you, uh, Ben. L- how do you, um… You know, there’s this question about sequencing for ski athletes. So just going o- out of role here. Um, do you wanna talk, Ben, about, like, when to start, um, like this sort of 10% rule that, you know, or guideline, rule of thumb that we have, like get aerobic threshold within 10% of anaerobic threshold before starting aerobic base?

You wanna kinda introduce that? Are you comfortable with that?

Ben: Yeah, totally. I think Martin just spoke to, you know, the stabilizing muscles are, are super important. That’s key. We talked about the base strength phase, and even some dynamic strength work before that can be really good as well. But yeah, I mean, to the point of, um, getting within ten percent, that’s, uh, that’s key before you start any muscular endurance stuff, I think, right?

Like, um, and really before I even jumped into any kind of zone three muscular endurance work where we even maybe do a little bit of a light weight to ease into that. Um, and even before doing the anaerobic threshold test, I think it’s important to warm up an athlete to doing intervals in a fashion where they can get used to those lactate levels a little bit and just what that feels like, right?

To be in a place where when they do get to that anaerobic threshold test, they can push themselves hard. We can see how their muscles respond, how their anaerobic system responds. And then after we look at some of that data, if we’re not within, you know, ten percent, that’s going to give us some data to understand how to structure the training a little bit differently. How quickly do we move into the muscular endurance stuff? Do we need to do more, um, aerobic work potentially, um, to get that aerobic threshold up to close to the anaerobic, um, threshold? But often we see some athletes that are in really good shape, you know, and they are within that ten percent, and that gives us an indication that, yeah, let’s jump into this work right away. Um, you know, start with some zone three stuff that’s not weight-bearing or that’s not like heavy weight quite yet, um, and then gradually ease into it. Gradually increase the weight, um, through interval fashions, right? Sometimes we’ll, uh, you know, we start– I usually start with something like three times five minutes, uh, working towards three times eight minutes, two times fifteen, two times twenty, um, one times fifteen, one times twenty-five, and then we’re to the place like, okay, we can start to handle that duration.

We can start to, and through that process, increase the weight. So we get to that point of being able to sustain a thirty-five, forty-five-minute Uh, zone three effort with carrying really, really heavy weight. So, um, like we said at the beginning, there has to be a progression to all this, and the ten percent rule gives us some information about where that athlete is at and how to structure the training to get them to that point

Steve: I think those are great points. And I just wanna zoom out a sec- a second and sort of bring together something that you both have talked about in that the the correct sort of periodization of strength training is to do four to 12 weeks of sort of general strength foundational, working on movement patterns, building and reinforce– you know, getting the connective tissue, uh, turn like– What’s the right word here?

Getting the connective tissue going. Um, getting the– I don’t have a good word. Well, there’s sort of four phases to this. We wanna start with general strength, which is gonna be four to 12 weeks, really foundational strength, developing good movement patterns, and do eight to 16 weeks or really eight to 12 weeks mostly of, uh, max strength, which is heavy compound lifts. That’s more of a neurological training. Um, we’ve talked about that in other places, a neurological effect of that training. Then, muscular endurance and then after muscular endurance, going into some high-intensity, uh, intervals. And one of the things that you’re talking about, Ben, and I’ve seen this, is that it’s really important for, uh, coaches who have not– There are a lot of coaches out there who have worked and have themselves been elite athletes, and when you’re working with somebody who has already done a lot of intervals in their li- their lives, like they kinda know what to do, they know what it feels like, they know how to go hard But a lot of times we’re working with people who this is pretty new to them.

And so, like s- you know, getting them to understand what a zone three feels like ta- you know, it takes more than just like one day. It takes more than one phone call. You know, it, it, it is some effort to, to build that up, and I think it’s really important, you know, and this is where the, the magic of coaching happens, and knowing who’s that person and who’s the person that you can, you know, just throw at a, throw ’em into a, you know, two-by-twenty minute, you know, zone three on their f- for their first ME workout, and that, that’s very, very different, uh, uh, people. For mountaineering, like someone going to Denali, Martin, like w- how do you see m- muscular endurance playing a role in people training for Denali or Everest? So one of these, particularly I think Denali, ’cause it has a really unique, uh, need to carry, I don’t know, heavy loads, heavy packs, and move heavy sleds just by yourself that no other climb I think really mimics.

Martin: Yes. Um, so it’s a good question, uh, how to actually put it in the plan, the periodization, and where it fits. So, um, again, it comes to knowing the specifics, the demands of the climb. Now we talk about the mountaineering. So, uh, Denali, uh, is really big one, right? And so the demands are really high, uh, especially the specific movements to pull the sled with the weight and also the heavy weight, uh, carry, uh, combined actually, both of them at the same time.

Depending on the quality of snow, you might have to actually carry most of the weight, uh, versus maybe if, if you’re lucky, you’re– it’s sliding really nicely. You’re pulling the weight and it’s, it’s not creating too much resistance. But it really depends. You should be, you know, you should, uh, hope for the best, plan for the worst.

So you sh- you need to be ready for if it’s really, really hard. And also that heavy carry up to the high camps, uh, where then it’s a really heavy backpack. Uh, it can be really icy, basically black ice. Uh, you’re on your front points. So really making sure that the athlete or the climber is ready for those demands.

Uh, so even, for example, the calf, calf strength there. So not, not, uh, forgetting that. Sometimes we forget and, uh, and within that specific, uh, muscle group, it’s actually mostly the isotonic, the, uh, isometric, sorry, isometric, the hold, isometric hold. So I’m– I like to include that in the protocol. Um, but, uh, now coming back to the planning.

So where does it fit in? So let’s say if I have one year for– with the athlete, that’s ideal. Of course, the longer, the better. So, um, w- the way I think about it is I have to see the athlete, where they are, what they have been doing so far, testing, seeing where they are with the aerobic base thresholds, um, and start from there.

Also, if they are planning some climbs in that year, I like to because, uh, it’s good to have some medium intermediate goals, uh, to test them as well in the– especially in the mountains.

Uh, And,

of course then the plan will Yeah, technique and all that. So cover all those demands, not just the physical preparation, the physiological parameters.

But when it comes to the physiological parameters, so, uh, we think about it in a way of how long it takes to get those adaptations? And usually I focus– I use the block periodization, um, so like, uh, focusing on, uh, like one intensity, not only of course it’s on the base, uh, of, of the aerobic intensity, but, uh, trying to increase the ceiling, the VO2 max also sometimes, but making sure of course, that the aerobic base is there.

But I like to also go from, from the end. So okay, the May, May, June expedition for Denali, and I kinda go backward. So I, I know that the last part really is specific, the specificity, one of the main training principles. So the training needs to be specific, the movements need to be specific, the duration of the training, the overall volume, and also the type of strength training, which is muscular endurance.

So the muscular endurance is really the last specific part of the strength plan. Uh, and it’s both the gym-based and, and also the weight it carries, sled pulls when it comes to Denali. It is quite similar honestly, with Everest, uh, metabolically at least, or what, what we are addressing, and I already spoke about it, what is actually happening, uh, within the muscle endurance.

So that also ties into the, the, the timeline of adaptations, right? The metabolic, the neuromuscular, those are usually the first ones. But we actually then, if we go backwards more, we come from the maximum strength protocol. So, uh, the muscles kind of know what to do, and now we hit them basically with the metabolic demands and, uh, the endurance part of the muscular endurance

Steve: Yeah, I love that framing of like getting the neur– you know, getting the neurological layer sorted out and then adding the metabolic demands, uh, on top of that. That’s, that’s the right way to think about it. Um, let’s, let’s, let’s talk a little bit about what muscular endurance training looks like. I tried to find a background picture for my screen today that showed, uh, hiking up a hill with a s- uh, backpack, but I wasn’t able to dig one out. This is, uh, close enough So one of you wanna walk, uh, walk me through sort of a typical heavy pack carry session. What does the terrain– what does ideal terrain look like? What kind of grade are we talking? Load, duration, how does the athlete know by feel if they have the right intensity?

Ben: Sure. I mean, I, I think maybe we can both add to this a little bit, but, um, you know, we, we ideally want this to be pretty hard, right? And maybe even some uneven, weird terrain like scree or, uh, using all your stabilizer muscles to be able to move your body with heavy weight, right? So, uh, you have to be ready for that right though too.

You can’t just jump into that. So I, I sometimes, um, like I said before, I start with lighter weight on these muscular endurance workouts with athletes, um, and then gradually increase the weight, gradually increase the, the terrain or the, the grade of the, uh, where they’re doing their workout. So it’s not any like this is your only muscular endurance workout where you need to find the steepest hill and put a sixty-pound pack on, right? I think it really varies just athlete to athlete. Um, and just having a nice progression is, is the best way to approach it. Um, and even doing stuff in the gym too, right? To help prepare for that too, like short rest periods, uh, box step up, step ups, box step downs. Um, if that’s the weakness of the athlete, like we can focus on that workout, um, and then move that stuff to the outdoors.

So, um-

Steve: One little trick I’ve used with people doing it in the gym is I’ll have them do the box step-offs. Step up one side and then have them step down on the other side, but have another small box there so it’s not as far. ‘Cause if you have a, a box that’s high enough for you to step up, it’s really hard to step off, especially facing outwards. So that’s a little trick for people. What do– what does, uh, what is the feeling, um, tell– what– how does the athlete know in their body, like what is the feeling in their body when they’re doing this right?

Martin: Yeah, I think in general, again, we, we should be limited by the muscles basically, not by the cardiorespiratory. So the breathing is not the limiter, the heart rate is not, uh, super high. It shouldn’t be. So I think then what, uh, what kind of weight we are using. Um, so I think it’s very individual, but also, uh, sport-specific and event-specific.

I like to kind of have two categories of non-specific weight and specific weight, because for some mountains especially, especially Denali, we talked about it, that one, you have to be ready to carry a lot of weight. Uh, you have to be independent up there. There’s, there are no porters. So I like to, uh, kinda use it also as a framework and, you know, build it up towards that specific weight that it actually usually covers even the demands for the muscle tra– endurance training because it’s heavy enough.

Uh, and otherwise, I think it’s using the percentage of body weight. I think that ensures, you know, like individuality and specificity. So if it’s, um, uh, fifty, fifty kilo athlete versus eighty kilo athlete, right? The, the, s- the relative weight will look differently, but it should, uh, should kind of induce enough stress for that given athlete.

And then we take it from there, and we build it up. Uh, I think what we usually see is the overall speed, uphill speed goes down a bit, which is good for me. It’s specific. It’s actually about that, the slow-twitch fibers working really hard, and they are– they now are really, uh– we are working on that capacity that you want, really postpone the fatigue, make them for like creating a lot of force, but repetitively and postponing the fatigue as much as we can.

Another thing I like to do is if the athletes have a way to do that, to basically go up and down a hill, like something like thousand feet, three hundred meters elevation gain, ideal, do it three times, and you can really see, like nice test of durability also. But also, I think that muscle endurance, how is that speed over those three laps?

A, you can compare the heart rate. You can– heart rate actually goes down to our point that central function is not a limiter. It’s actually the fatigue building up in the muscles. And, and so over the phase, we are able to see the progression. We– They are able to keep the pace.

Steve: Yeah. Yeah. Yeah, great. And I think that one of the things that people always ask is like, “Well, I don’t live in the mountains, what do I do?” And, you know, I always say, you know, the, the first choice is something that uses real gravity, like walking up and down stairs or stadium steps. The next best thing is probably a steep treadmill. Third best is probably a StairMaster. And when we think about this, you know, we do want the legs to be burning, but The conversation to still feel possible is sort of one of the ways to think about it. And it’s, uh, often– and if you don’t get to that on the first workout or even the second or third workout, don’t be surprised because it takes time to dial in the, the location, the how, you know, just all the, all the variables.

There’s a lot of kinds of gear involved, like how do you, how are you weighing your pack? Are you– do you have enough water bottles? There’s just a lot of logistics that go into getting these workouts right, and it’s, and it often takes a few tries. I also wanna say, like, it’s almost never steep enough to go up a trail or a road.

Like, you have to go up a… ideally, you have a ski run. You can go right up the fall line of the ski run, or you go up the s- the slope, um, somewhere where you’re not, you know, you know, not causing too much erosion and, and go up a scree field, something like that. But, you know, we’re all limited by the terrain we, we have around us.

Here where I’m sitting, like, there’s steep hills, but they’re cover- they’re pretty, it’s pretty forested, so it’s pretty hard to go straight up the fall line on, on these hills here unless I have a, something like a ski run. So let’s shift to the gym. What does– We’ve mentioned this a couple times, but let’s sp- get really specific.

What does a gym-based muscular endurance progression look like? I gotta say, like, probably most of the athletes I coach are doing this in the gym. There’s just not that many people that have the right terrain to do this outside. So what does a, what does a gym-based ME workout look like, Ben?

Ben: Yeah, I mean, I, I think we, we kind of spoke to it a little bit, but, um… And, you know, I, I think in the base strength phase too, there, there’s– It’s not muscular endurance, but I, I often have athletes do, uh, more reps with more rest, right? In that base strength phase, and it kinda just adapts their body in a way to be able to move on to that, uh, max strength phase.

So by the time we get to the, the more muscular endurance aspect, like, yeah, we might have some, some longer rest periods, but really trying to shorten those rest periods as much as possible, right? and and doing a, like, a box step-down workout and then do– going to do something else like push-ups or pull-ups right away.

It’s, it’s kinda– I mean, pe- we talk about this, people think maybe like CrossFit, but it’s not like CrossFit of the high intensity one thing to the next. It’s really the, the time and the duration that’s, uh, bringing those muscular, um, endurance adaptations. It’s just the short rest period and then the long sustained box step stones, box– And I mean, we’re talking about– Martin said again, it’s specificity, right?

So, um, someone that’s running a marathon, that could look a little different. How do we train that in the gym? It’s a little bit more difficult, right? They just need to go run like for hours and hours. Um, but we can do stuff that’s less intense with less weight, just more like lunges, right? That’s not necessarily weighted, but lots and lots of lunges and short rest periods.

Um,

Steve: are great. Yeah.

Ben: I don’t know. Martin can add to what his ideas on gym-based muscular endurance as well.

Martin: Uh, yeah, I think so. I mean, I agree with you. I think, uh, we can split it into categories of like two-legged squat versus the unilateral squat. And I think those unilateral squats in that, especially the last stage, are more specific to us endurance athletes because we are ultimately doing that, uh, whether you’re running or hiking or, or especially uphill hiking or downhill hiking, right?

So, uh, it should be some version of that. So box step-ups for the uphill, I think that’s as specific as it gets. Uh, you can control the movement relatively well, and it’s, as you said, I think it’s just the important part there. It’s about the time, the duration of those reps, and you should start to feel that kind of aerobic, we can call it maybe aerobic part.

You start to– The b- the breath and the heart rate goes up because the demands are all of a sudden very different to classic strength protocol, which is about low number of reps. Your, your– The energy metabolism is completely different, so we’re actually going to that endurance part of the muscle endurance.

Um, yeah, so the box step-ups and lunges or some kind of dropping the weight down and doing reps of it. Maybe jump rope also. Maybe that’s more for the dynamic movements of running. Uh, some kind of, uh, as I mentioned, the calf, something for the calves, maybe simple calf raises, uh, and drops, of course, but then, uh, maybe also the isometric holds for some of those mountaineering, especially ice climbing or parts of the climbs where you are, you know, on your front points, uh, which can be on Everest, which can be on big mountains on Denali.

Uh, I, I would also include it, include there. So it’s not necessarily reps, it’s actually the holding in that specific position, uh, for a certain time.

Steve: Let’s just do real quick some of the common mistakes that you’ve seen. Ben, you wanna– Is there something that you’ve noticed that people get wrong about muscular endurance training?

Ben: Yeah. Well, a lot of my athletes, some of them, they, they, they like to– uh, when I, when I prescribe a muscular endurance workout, like when we’re really into this specific part of it towards the end of their training, um, they think that they should be carrying this really heavy weight also on their, their long workouts, right? On their three, three to five-hour hike, zone one, zone two. And I, you know, I try to communicate to them that we, we, we ha– we need to balance out this training stress, right? And we need to be very specific about this muscular endurance work. If you’re going out and doing three five-hour hikes, um, and trying to get your aerobic work in during that and carrying a huge pack, that’s not what we wanna do. So that’s probably the, the most common s-mistake I see, is that people wanna jump in. They say, “Oh, I’m, I’m carrying this weight on my zone three muscular endurance workout. Why can’t I do it on this three to five-hour workout? And I, I should be doing that too because why not, right? It’s making me

Steve: More is better.

Ben: Yeah.

Steve: Yeah.

Yeah. Yeah. No, that’s a great, that’s a great, uh, point and a common area of, of misunderstanding and, um… Yeah. Let– Martin, how about you? What’s, uh, what’s something that you’ve seen people not underst-

Martin: Yeah, I think there are several of maybe forgetting the downhill part. Um, maybe, um, not using terrain steep enough or actually doing the rucking, which is the hiking on flat, thinking that it will be good enough. But we just– I just try to explain to athletes that for most people, this is just not hard enough.

Uh, you’re definitely doing something, but, uh, you’re getting better at hiking on the flat, basically carrying some weight. It might be worth for those upper body muscles to keep the posture. I think that’s– there’s a benefit, but you need to be efficient with your time, and most people are busy, so that one session is a kind of a lost opportunity.

It really needs to be specific. And the most– I think that one of the most important factors when it comes to mountaineering is the uphill part. We have to do a lot of work to get ourselves up the hill against gravity. That’s the physics, right? It’s the body mass plus the m– the, the weight of our gear, uh, the gravity factor, uh, times the elevation gain.

And that’s pretty much the energy that our body, our muscles, need to produce to get us up there with less and less oxygen and altitude. So, uh, it’s– the math is clear. We need to be specific. We need to get those muscles ready for the specific incline. Yeah, I think that’s, that’s one of the, the big, uh, the big, um, mistakes.

Um,

Steve: yeah.

And the other one I would add is that people get addicted to it, in the sense of they do it for six or eight weeks, and they’re like, “Wow, this is amazing. I feel so great. I’m gonna do this all the time.” And, you know, then they hit a plateau, uh, they start to detrain. You, you know, this is why we have– this is why training needs to be periodized.

It’s sort of a living example of that. You can’t just do muscular endurance training all year, uh, and continue to get better. Can– You can do it for probably maybe 16 weeks and, and, and get better if you’re paying attention, but anything beyond that is, is really probably just, uh, science fiction. What do you say, and neither of you can take this, but what do you say to an ultra-runner who says they don’t do weighted carries, they just do steep uphill repeats because they think that’s the same thing?

Like, what, what’s your answer to that? How do you explain the difference between, like, an uphill, uh, unweighted fast run, like hill repeats, versus a muscular endurance workout?

Ben: Yeah, I mean, I think it, uh, you know, we, we need to isolate the, the muscles here, right? And we need to, like, really focus on the strength aspect of, of what we’re trying to achieve in that workout. So if we’re just doing up, uh, uphill repeats, um, and maybe that, that ultra runner is, like, really tapped into their– real-really fit, really tapped into their anaerobic system and, um, and they’re, they’re pretty strong too, right?

But we need to add that training stress of adding some weight and making it really, really hard. I mean, that’s the point is, like, is building the durability through the legs, right? So I guess that would be my answer is you gotta make it hard.

Martin: Exactly.

Steve: Yeah, And I think you have to load the muscle

Martin: like to

Steve: get some closing thought. Oh, go ahead, Robert.

Martin: I-I’d like to add is I like to use this example. Last year I was, uh, in UTMB race here in Chamonix. So, um, I went to watch the top three women in Champex-Lac, which is, uh, the point where they’ve been running for a very long time. Uh, what is it like? It’s fi-fifteen hours, I don’t know exactly, but they still have quite a long way to go, about fifty-five kilometers to Chamonix.

So they’ve been on their feet for hundreds, uh, ten hundred to twenty kilometers, uh, all the night and part of the day. And so there is this, um, nasty climb to this Champex-Lac, where there is a refreshment point. So I, I was– I saw the three women. They were quite close to each other, and the, the difference…

They were hiking, huh? At this point, most of them are hiking, most of the people, and even these three female athletes. The difference was quite impressive and quite clear. I mean, of course, there are the other factors playing, o-overall fatigue. But they are– they were not breathing hard. They were not out of breath.

It was the, the muscles, the leg muscles, the way the, the cadence, the form. You could see who’s training the muscle endurance, if we can call it, and who’s not. And so I think most, uh, runners, trail, trail runners especially, I mean, uh, when it, when it comes to running a lot of mileage in the mountains, they don’t realize that you will hike a lot of the big part of the, of the distance.

And so you think hiking will be easy. I, I will just train the running. So this is, I think, a big mistake that the, the trail runners make, especially ultra. And, uh, so– And as Ben said, isolate that factor, right? And as you, Steve said, make it hard, make it slow and hard so that you actually really target the specific local muscle endurance.

Uh, so I think that make, that can make a huge, huge difference.

Ben: Yeah, I had a– my story is the same. I mean, I, I did a marathon in November. I didn’t do any muscular endurance training, um, you know, and I, I felt great. Like, my, my my card– my aerobic, anaerobic systems were on fire. Like, I did– ran sixteen miles and felt great, right? And then my legs gave out, and my heart rate went way down.

And I was like, “If I would put me on, like, cross-country skis or put me on roller skis right now, I’d take off,” right? But, you know, that, that’s the– that was a limiting factor, so

Steve: Hmm.

Ben: it pays

Steve: Yeah. It’s a great ending note. Martin, what’s your c-closing insight as we wrap up here?

Martin: For me, I mean, it’s, it’s really important to understand what is behind like muscle endurance to, I think, uh, having the definition in front of you to actually understand what’s behind. Uh, maybe another anecdote actually to finish it with is, uh, the high altitude mountaineering. So I really thought about this when I was going to, to the Manaslu, to the top of Manaslu, uh, a year and a half ago.

And, uh, I think I did well, actually. I was not limited by my muscles. I, I could go faster. I was actually limited by the other, which is the altitude. I was not acclimatized enough, so I was just out of breath for this. My body was really struggling with, uh, with that. The muscles were great. Uh, I was, uh, I was like, “I just wanna go faster.”

Uh, another thing to, to add to that is the studies about Sherpas. I think people know about Sherpas, their enormous capacity to carry heavy loads, to help people, to carry down people if it’s needed, actually, sometimes. And so we can guess that, uh, their muscle endurance is, is, uh, enormous. And actually, the studies that I’ve read, the– actually you can see those things that we discussed, the physiological many factors within the muscle endurance, they are there.

Their bodies adapted genetically over generations in these unique, uh, factors. And of, of course, that makes, uh, their muscle endurance, I think, in a high level. So I think we can take it from, from them. We should, we should, uh, train that because it will be important up there in the mountains.

Steve: Ben, any closing insights about durability?

Ben: Yeah, I mean, I, I think this is, uh, it’s a very important part of training. Like, um, everybody thinks about it, talks about it. It’s a huge topic, um, but it’s a very small part of it, right? So like you said before, if we’re gonna just hy- be hyper-focused on this and try to do it all the time and make those gains by jumping in too early with it or doing it for too long and not doing it in a structured, you know, specific isolated way, uh, it can be a real detriment to your training.

So I think it, it certainly pays off to, you know, ideally get a coach, um, at least get a training plan and understand these ideas of everything that goes into your endurance training so you can, uh, most effectively do these workouts and make it count and make it actually work for you. So small part of our training, but, you know, super important.

You can’t neglect the rest of it.

Steve: Yeah, muscular endurance is not a secret. It’s been known, and it’s been studied in sports science literature for decades. We have great articles on the website explaining the full methodology, workout progressions, weighted carry protocols, gym-based muscular endurance workouts that you can follow. That’s all free.

Go read it. Check out the aerobic threshold and anaerobic threshold testing guides. And before you start a muscular endurance block, be sure you know that your AET aerobic threshold is high enough to, uh, accommodate the, the work of

the, of the muscular endurance training. The ba- the aerobic base prerequisite is real. And Ben, as you just said, people should use a training plan or even better, a coach. If you want personalized guidance, all three of us are currently taking athletes. So thank you very much, Martin and Ben. Thanks to everyone for listening. Go earn those miles, and we’ll catch y’all on the next one.

Steve: One of the most common questions I get is, “How should I get started with training?” Well, they say the first step is the hardest, so let’s make that easy. We are offering three four-week samples of our most popular training plans for mountaineering, trail running, climbing, and more. Go to uphillathlete.com/letsgo to sign up for our newsletter, and you will not only get monthly insights on training for uphill athletes, but you’ll also get a sample training plan.

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