TRANSCRIPT

We’re between 20 and 40 stronger in an eccentric muscle action than we are in a concentric muscle action. I love the idea of my muscles are working harder, but it feels easier in the moment to me, which has implications for my motivation to keep going. Welcome to the Strength Changes everything podcast, where we introduce you to the information, latest research, and tools that will enable you to live a strong, healthy life. On this podcast, we will also answer your questions about strength, health, and well being wellbeing I’m Amy Hudson I own and operate three exercise coach studios.

My cohosts are Brian Sagan cofounder and CEO of the exercise coach and Dr. James Fisher leading researcher and evidencebased strength training and now for today’s episode Welcome back to the strength changes everything podcast today. We are discussing all things eccentric training. If you’re an exercise coach client you probably are familiar with what eccentric training is but today we’re going to break down everything related to eccentric muscle actions. This has been well understood for many years by by labs and coaches and highlevel researchers and one thing we do at the exercise coach is we bring this magic training to the masses at scale but today’s episode is all about eccentric training. We’re going to talk about what it is. We’re going to talk about some examples of eccentric muscle actions, what makes it beneficial, some critiques of it, some recent research that has come out about this and kind of what this means.

And my hope for you listening to this episode is just for you to understand at a deeper level how capitalizing on eccentric loading can help you gain strength faster and achieve your goals faster, which is really what we all want, isn’t it? So, Dr. Fisher is with me today to talk all things eccentric training. How are you today, Dr. Fisher? I’m doing a fantastic day, Amy. Thank you. How are you? I’m great. I’m great. And eccentric training is super exciting. I know it’s a little bit niche of a topic, but I mean, I’m super excited to get into it because I think once people understand this, it can be pretty exciting for them to think about how leveraging it in their own personal workouts may help them. So let’s get into it. Would you like to start by just talking about kind of like what it is?

Yeah, yeah, fantastic. So, first of all, thank you for kind of catering to me on this one. I’ve read a recent paper which we’re going to get into and I’ve really kind of pushed that. I think this is a conversation worth revisiting. And a big part of it is the academic in me that’s kind of always excited by the science, but I always want to be able to take a research paper and try to deliver it to the general population so that it doesn’t just sit within that academic realm and the information is never kind of trickled down. So let’s start by briefly just highlighting what an eccentric muscle action is. So when we contract a muscle, there’s a concentric phase where the muscle shortens and we lift a weight. So if we’re doing a bicep curl, that’s our forearms coming up and it’s our lifting of the weight.

If we do an isometric muscle Action that’s where there’s no movement at the joint so that’s effectively our arm locked in place and we’re just holding the weight in place. And then an eccentric muscle action is the lowering of the weight but it’s our resistance of the weight. And I’ve always kind of described it that way and then given realworld examples World examples but in fact the real world examples make the understanding hopefully clearer. If you walk down a hill then every time you put your foot down you’re breaking, you’re slowing yourself down from falling, you’re resisting.

That’s exactly what you’re doing in an eccentric muscle action. In fact that is an eccentric muscle action. So if we push off, that’s concentric because we’re pushing, but if we’re resisting or if we’re slow that’s eccentric. And so, eccentric strength training or eccentric training of any kind has real world application in everything we do. If you can imagine, if you are sat down and you rise from a chair, that’s a concentric muscle action. But if you’re stood and you lower yourself into Stood and you, and you lower yourself into the chair, I was about to say collapse into the chair, hopefully not collapse. But if you lower yourself into the chair controlled, that’s an eccentric muscle action. So straight away, we can see that in, in the real world, as we get older, those are things that we might struggle with. Both are lifting us off out of the chair, but also are controlled, lowering ourself into the chair.

Maybe as we get older, it becomes more of a collapse into the chair. But we want to avoid that. So those are some that hopefully Give some clarity first of all if what concentric and isometric as well muscle actions actually are. We have highlighted them before but they’re always worth kind of revisiting. Okay that was a great explanation and when your muscle is contracting and shortening I know we can call that concentric muscle action right? As some people call it, it’s called concentric muscle action where our body moves because because our muscle shortens to move in a certain way, and then eccentric muscle Action in the examples that you gave, our muscle is lengthening, right? Yeah, their muscle is lengthening under load. So the load is effectively pulling down on the limb. So that’s trying to move the joint, but we’re resisting that movement or we’re slowing that movement by still sending signals to our muscle to provide force, albeit that we’re allowing the muscle to lengthen.

We’re not producing so much force that we lift. The weight back up again. Got you. Okay, so why is eccentric training important to pay attention to and why is it so kind of a hot topic in the research world and in the sports world and coaching world? Okay, so one of the things that really excites me as an academic and as a researcher is that eccentric training is a bit of a what’s what we thought of as a physiological phenomenon. So we’re between 20 and 40 stronger in an eccentric muscle action than we are in a concentric muscle Action. So if you can lift 100 pounds you can lower 140 pounds and that’s an amazing thing. That’s quite phenomenal that our body has that capacity to lower weight with control that’s so much greater than the force we can produce concentrically. But it gets even better because it can do so with lower physiological demand.

So if we were to look at how much oxygen you’re using, if we were to look at your breathing rate, if we looked at your heart rate, if we even asked you how hard a set of 10 repetitions felt, it would always be easier. Your breathing rate would be lower. Your heart rate would be lower for the eccentric muscle actions compared to the concentric. So your body can do all this extra work eccentrically, but even a lower metabolic cost than concentrically. And that’s why it’s such an interesting factor for me. And there’s still so much research going on around it because it kind of defies what we generally think of as physiology. That is so cool. I mean, if you’re listening to this, then I love the idea of my muscles are working harder, but it feels easier in the moment to me, which has implications for my motivation to keep going.

And I’ve even heard as you fatigue. That differential between what your muscles can do on that eccentric contraction versus the concentric gets greater and greater than 40 like it might be hundreds of percent difference in what you can give the output on an eccentric versus a concentric as that fatigue sets in, which is, is that true? All the more amazing. There’s definitely some research that’s shown that as we fatigue and our concentric force output reduces, our eccentric force out certainly doesn’t. Doesn’t reduce to the same extent. So if you do 10 repetitions, by the 10th repetition, your concentric force is, you know, maybe you can barely lift.

The weight, but eccentrically, you can still lower the weight under control. So you’re now, you know, much, much stronger eccentrically than you are concentrically. So, yes, there’s a greater disparity as a result of fatigue. Okay. So, like, just in case somebody isn’t 100 connecting the dots here, so because we’re working harder, I mean, we’re working harder. So, what does that mean in terms of somebody’s results if they are able to really more capitalize on eccentric training? Yeah, well, it’s interesting because you say we’re working harder, but from a physiological and a perception response, we’re not working harder.

Our body is achieving more, we’re producing, we’re capable of producing a higher force output, but our body isn’t having to put as much in. And what’s really fascinating about this Is that often leads us down a path of thinking, oh, well, in that case, it’s obviously not productive because I’m not working hard. You know, we’ve been led down this path of, oh, if you’re not in, you know, in agony at the end of a workout, if you’re not, you know, lying on the floor, barely able to breathe or stand up, and if you’re not sore for days after a workout, then it wasn’t productive. We know all of those markers are really nonsensical. They’re not what determines what a good workout is. We know that eccentric training. Is a productive component of a workout almost no matter how you feel. After the workout or you know immediately and how you feel for days so you don’t need to have that delayed onset muscle soreness and again that’s partly why I wanted to come back to this topic because this paper does a really great job.

The paper by the way I should highlight is by a guy called Ken Nosaka and it’s titled eccentric exercise muscle damage to the new normal. It’s a 2026 paper published in Journal of Sport and Health Science and we’ll try and link to it in the in the share notes. But it highlights that in The show notes. But it highlights that it’s not all about muscle damage and soreness and stress and all of the kind of what we think of as the negative components of exercise. That a lot of the benefits that we get from eccentric training are even without those almost those negative elements.

And in the paper, I’m going to jump ahead a little bit. In the paper, he talks about one of his earlier papers with multiple colleagues. And this was a paper by the first author Chen et al in 2017. And what they did is they had Two groups of people, the first of which walked up a flight of stairs and got the elevator down, and the second of which walked down a flight of stairs and got the elevator up. And these were elderly, obese women. So they were a group of people that you were never going to give really arduous exercise to. They were never going to be physically capable of doing incredibly strenuous exercise. And again, that almost highlights that. Ecentric exercise can be really beneficial for everybody, but is very palatable by maybe older people or people that don’t have as much experience in a gym environment. Anyway, so going back to the paper, one group walked up the stairs, one group walked down the stairs. And at the end of 12 weeks or after each session, they would ask them how hard they worked. And there was a lower rating of perceived exertion for the group that walked down the stairs.

So, as you would expect, so walking down. The stairs remember is our eccentric training and walking up the stairs is concentric. So they’ve done less, they’ve perceived to have done less work but after 12 weeks and I’ve got some details of the paper right here so forgive me looking to one side to try to bring these up. After 12 weeks they found that there was greater improvement in cardiovascular function so resting heart rate had reduced by 10 compared to 4 there was a greater reduction in systolic blood pressure of 9 compared to 3 there was a greater reduction in insulin sensitivity of 12 to 0 so no change. And a reduction in low density lipoprotein cholesterol of 13 compared to no change. And a greater increase in maximal isometric strength of the lower body of 34 compared to 15 all in favor of the eccentric training group. So they’ve done 12 weeks of walking downstairs, reported that it was easier compared to the group that walked upstairs, and yet they’ve had all of these incredible physiological benefits. Wow. Wow. That I. I’m really surprised to hear that those are pretty significant changes in areas that you wouldn’t expect in kind of a short amount of time, all based on eccentric training.

Yeah, it’s quite phenomenal. And that’s kind of exactly where we’re going when we talk about eccentric training that there’s this capacity for these incredible physiological improvements, but without the same perceived exertion or perceived stress or demand. And interestingly, they also reported that there was no muscle soreness in this group. And it kind of, when I think about this study and I reread over this study, it reminded me of the conference that we had back in May. So obviously, we were at the hotel and everybody, all the franchisees are staying at the hotel and speakers are at the hotel.

And I saw multiple franchisees walking up and down the stairs, which was great to see, by the way, rather than constantly use the elevator. But interestingly, it made me think somebody once said to me, Oh, so you’re taking the stairs as I set off to walk up the stairs. But it made me think, actually, what they should have said is, Oh, are you taking the stairs down? Oh, yeah. Because that’s where the benefit is, right? So next time you’ll have to say that to them and then you’ll have to have this whole conversation with them. Exactly. Exactly. I think this is exactly where we need to go. So this kind of highlights a few things. So, and the author gets into this, Ken Lasaki gets into this. He sort of says, Eccentric exercise should become the new normal. You don’t need to feel wrecked to get results. You don’t need to push through pain. They don’t need to be long workouts. There is the capacity for muscle soreness from it, but the repeated bout effect tells us that if you do some part of it once that doesn’t induce soreness, that prepares you for harder work in subsequent sessions, which might have induced soreness had you not done that initial session.

So you kind of adapt to it as well. So it’s just a Phenomenal kind of training component within physiology and of course the purpose of all of this discussion is if you’re a client of the exercise coach then you’re well aware that the exerbotics equipment that you’re training on can emphasize the eccentric component. So you’re able to resist a greater load as we talked about earlier on your physiological capacities you can produce more force in the eccentric component and the Exobotics equipment will give you that load allowing you to produce that more force and further improve Your eccentric strength and your physiological adaptations more so than traditional weight stack resistance.

You can see and imagine how it would be challenging to achieve the same level of eccentric loading on a gravity based exercise as compared to a device that has this bio individual adaptation to one’s different ability, concentrically. And eccentrically, right? Yes, the special thing about X Robotics and the way that powers our eccentric training and the workouts that clients get is because of the fact that it is bioadaptive. It’s allowing you to achieve the exact stimulus that is appropriate for you, both on that concentric and eccentric repetition, every second of every exercise. So it does make it so much easier to distribute this.

The researcher recommended it should become the new normal, but it is hard to make it the new normal without that technology, isn’t it? Absolutely. Absolutely. But as we highlighted, this is what makes the eccentric component so beneficial for older adults or clinical populations or previously sedentary individuals who are putting foot into the gym for the first time. It’s not a traditional weight stack machine where there’s a weight moving up and down. It’s, as you said, bioadaptive technology. Where the resistance matches their strength through both the concentric and the centric muscle actions. Right. Well, I love this because it’s so encouraging to no matter the population group and I mean I think everybody can see the appeal of you know why eccentric training is so is so positive. I’m glad that this paper came out. I mean what are your other takeaways from this that you’d kind of want listeners to know? I just Think that from the purpose of understanding that there is an eccentric component to daytoday activity, it’s important but then understanding that if this can be incorporated into training and it can be, then it should be because of the potential benefits both in that it’s lower physiological stress but it’s greater physiological adaptation.

You know, with the exercise coach we talk about the training being, you know, efficient and it’s not just that this is efficient, it’s quite literally the most efficient because it’s lower demand and higher outcome. Absolutely, and who doesn’t love that, right? Excellent. All right, anything else you wanted to hit on today about this research paper, Dr. Fisher, or about this topic? No, I think we’ve covered all the key points there. Thank you. Well, I’m super jazzed about Eccentric training after listening to today’s episode, and I hope you are too. Go do your workout. Let’s enjoy that eccentric component that we are leveraging every second of those reps, and we will see you next week on the podcast. Until then, we hope you remember strength changes everything. Thanks for listening. If you enjoyed today’s episode, please share it with a friend. You can submit a question or connect with the show at strengthchangeseverythingcom Join us next week for another episode and be sure to follow the show on Apple Podcasts. YouTube, or wherever you get your podcasts so that you never miss another episode. Here’s to you and your best health.