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Expand your running knowledge, identify running misconceptions and become a faster, healthier, SMARTER runner. Let Brodie Sharpe become your new running guide as he teaches you powerful injury insights from his many years as a physiotherapist while also interviewing the best running gurus in the world. This is ideal for injured runners & runners looking for injury prevention and elevated performance. So, take full advantage by starting at season 1 where Brodie teaches you THE TOP PRINCIPLES TO OVERCOME ANY RUNNING INJURY and let’s begin your run smarter journey.
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On today's episode, the right strength training to improve fatigued running with Michele Zanini. Welcome to the only podcast delivering and deciphering the latest running research to help you run smarter. My name is Brody. I'm an online physiotherapist treating runners all over the world, but I'm also an advert runner who just like you have been through vicious injury cycles and when searching for answers, struggled to decipher. common running myths and real evidence-based guidance. But this podcast is changing that. So join me as a run smarter scholar and raise your running IQ so we can break through the injury cycles and achieve running feats you never thought possible. First up, apologies for this episode getting out a couple of days late. The reason behind it was I had this interview scheduled and not only do I have this one scheduled, but I've got some bangers coming up in the next couple of months. I've tried to work out when certain episodes get released, at what dates, and I have been booked out up until mid-June. Unless, you know, some scheduling conflicts happen or people can't make their interviews, that tends to happen. But really didn't have this one that could be scheduled in unless I released it a few days later as this week's episode. Otherwise I'd have to wait several months and this one was too good to pass up to wait that long. I'm getting quite impatient. thanks for waiting a couple of days for this release. We're going to talk about a research paper, which my guest has been an author on. The title of the paper is Strength Training Improves Running Economy Durability and Fatigued High Intensity Performance in Well-Trained Male Runners. randomized controlled trial. One of the co-authors of this paper was Rich Blake Grove as well, who's been on the podcast a long time ago in the early days, I want to say in the first maybe 20 episodes he appeared. And this paper particularly caught my eye. So reached out to Michaela and asked, and I'm grateful that he agreed to come on to the podcast. We're going to discuss this around running economy, durability and fatigued running. and some particularly really good insights with that and how it can apply to recreational athletes. If you like Michele's work, I'll have his Blue Sky, LinkedIn and X handles in the show notes for you to go follow more because he's releasing some really good stuff on those platforms. And if you want access to this paper, it is now in the Google Drive for you research database members. It will be in the March 25 folder and over the next couple of days, I'll just be completing and finalizing March's papers as I next week will record the latest running research episode. This paper is really good, some really detailed graphs around the improvements of the intervention group compared to the control group across a whole bunch of variables, as well as photos of the exercises themselves and the table of all the exercises, the sets and reps, the rest periods and how that progressed throughout the 10 weeks. So if you are a member, Go check out that paper now. If you want to learn more about becoming a member, it will be in the mid-roll ad. So can listen to that to learn more. started my PhD at Loughborough University in 2020, mainly in the area of the durability. It wasn't a thing back then. It is becoming now. So how performance determinants change as we fatigue and how can we try to delay that fatigue process? And as a background, I come from running, was an 800 meter runner and I was coaching and I still coach now. I had a series of good opportunities to be involved with internships and then actually working with Kenyan runners with a couple of Italian coaches that are still based there. Claudio Bernadelli, first of all, he's the coach of Manuel Wagnoni and Benson Kipruto, among many others. So Olympic champions in the 800 meter race. at the Olympics and third at the Olympics. I still kind of, I wouldn't say closely, but I'm still very much in contact with Renato Canova and we've done some work together. So started working with his team as a strategy conditioning coach. And then on the back of that, started my PhD in that area. Finished my PhD in 2024. So like a few months ago. Well done. Congrats. Thanks. Yeah. It's a huge effort. I am very happy about getting that done, but it was a very enjoyable journey. I think having good supervisors made a lot of difference on that. And now I work as a lecturer at the Open University. So lecturing in sport and exercise science and still do research in applied science, mainly to endurance sports and running. Very cool, mate. What inspired this most recent study? Like I guess in the intro that I already recorded, I would have mentioned the title of the paper, but can you bring people up to speed in how this topic and this study started out? Yeah, sure. So I think we can probably look at it from a couple of different perspectives. The first one is about how strength training is known to enhance the running economy. There's a lot of evidence and reviews on the topic showing when an unfooted state, strength training tend to have a positive effect on economy and therefore on running performance. What was unknown when we designed the study was if a positive effect would carry out on longer durations. We know that up to about 30 minutes of exercise, there's usually a positive effect of strength on economy, but then we don't know if that effect is carried out farther and therefore has potentially a positive effect on durability as well. When we speak about durability, which is the other aspect of the study and the main focus of my research and PhD, we're speaking about acute change, acute deterioration of physiological determinants and potentially speed or power at thresholds or maximal efforts that can be produced and that can come from cycling, running or other endurance sports. what we've been mainly focusing in my PhD and what we were mainly interested here was running economy and how that durability can potentially be improved. So now durability can be also defined as physiological resilience, which at the moment in research, they kind of use interchangeably. There will hopefully be some clarifications on what it is what instead of just keep using both terms in the same way. But at the moment, they kind of express the same physiological deterioration in efficiency or your to marks or physiological threshold that you do acute fatigue. Yeah. Very good. Well, I know you're very aware with the changes or the improvements in running economy that strength training can have. know Rich Blake Grove was one of the authors of this study as well, who has been on the podcast years and years ago. And I've got his book on my, my bookshelf behind me. Um, so very clear that there's good evidence that. strength training can help improve running performance. Um, but that's why I was particularly interested in this paper because running economy durability was a term that I hadn't really come across, but also that fatigued aspect. Um, I was like, Oh yeah, I wonder like that has, I haven't really come across many papers that have looked at, I guess they've looked at, um, durations around about 60 to 30, uh, 60 to 90 minutes, but probably not beyond and why those mechanisms are in place. So. um, worth designing a study around exploring those particular elements. And so how was the study designed? Can we maybe start off, we'll cut into pieces. Maybe we'll talk about the population that you selected and why did you select that particular population? We wanted to have runners that were used, accustomed to do an exercise, which is, has been kind of the hardest beat. uh, like getting people that are willing to be on the treadmill for 90 minutes at a relatively high intensity and be okay with that. We didn't want to have like a huge amount of dropouts due to the effort or duration. So criteria was among others, be accustomed to run longer than 90 minutes, not necessarily on a treadmill, but that goes without saying. and, uh, performance wise, we decided to have a cutoff of 50 minutes over 10 kilometers. We had other studies done before in a similar way in our cross-sectional design. So we knew that if we wanted to get an initial sample size of about 40 people, we should have probably aimed for about 50 minutes or more in the 10-kilometre time. We couldn't go on for half a marathon time, sir, but that would have potentially limited the... The pool of athletes that may come from slightly shorter distances, 5k, 10k races, which they still do long runs in the weekend. So we wanted to capture everybody that would be involved in distance running, meaning 5k upwards and accustomed to long runs. So well-trained male athletes. I saw in the paper that the population size was about 38, which seems quite substantial. Like a lot of these. strength training studies that I come across. It's like we trained 12 well-trained male athletes. And it's like, well, 12 is okay, but it's not great. Were you happy with the numbers that you ended up with at the end? Yes. I think we were very happy about that. We ended up with 28. So we started with 38 and then ended up with two groups of 14. I think this is one of the studies with the largest numbers. When we were looking at inter-randomised controlled trials for strain training applied to running. It is very difficult to recruit high numbers for training interventions, mainly when they go beyond six weeks. So I think we've been lucky at some extent with a lot of people that were actually very engaged, both in the control and in the exercise group. So if we look into the... the retention rate, not sorry, not the retention rate, the, basically how many people they came to the sessions and how many sessions they've done. We had a 99 % of them doing pretty much everything. So like a couple of hours, we just missed one session out of the 20 and everybody else did all the sessions. So this is very, very good for this type of studies because it is. big commitment for participants. And even from a control perspective, we didn't really lose that many when we had to do the running test at the end of the control period. So I think we lost maybe two or three that just didn't respond to our requests. And again, based on the experience we had in previous studies, we... We knew how we could provide value to the athletes involved. So besides some of the data that they had access at the end of the training, and of course, for those exposed to the training, they got a free training plan for 10 weeks. They also got a full physiological report on their strength and weaknesses and how they could work on those. And that has been very effective in retaining athletes for different studies. probably like six, seven, eight artists that we've tested here. I've also tested in previous experiments with them. Gotcha. Yeah. I know if a lot of runners like data and if they're going through a study where, you know, you're constantly measuring the numbers and seeing how they prove if any, then it's usually quite helpful to be tested in that particular way. With that said from like a, From the recreational runners who are listening to this podcast, what baseline measurements did you take and what measurements did you record throughout the study that you think that recreational runners might be, might find particularly useful? Yeah. So, um, we did some testing before and after, then a few tests in between the fifth week, but those were basically only for the strength group to adjust the weights. I wouldn't go into too much details of that, but for the pre-post testing we did the initial testing as a physiological determinant, so thresholds, economy and Biotomax. That was done only at baseline and we decided not to do it post-training because there's practically no studies showing any positive effects of strain training on Biotomax or thresholds, so we wouldn't have expected that to occur. And then the main... aim was then to look into the effect of strain training on the changes in physiological responses during the prolonged run. So we had a 90-minute run at 10 % delta between LT1 and LT2. What does that mean? It's that we take the speed of LCT1 and then we add 10 % of the difference between LCT1 and LCT2. So if we get lactate threshold 1 as, let's say, 15 kilometers an hour and lactate threshold 2 at 20 kilometers an hour, we go for 15 plus 10 % of the difference between 15 and 20 kilometers an hour. So it is very close to lactate threshold 1, but it is above the threshold, which helps ensuring that we are exercising in the heavy intensity domain. We chose that intensity, which is quite demanding for these athletes, was about 80 % of youths max, because that is very closely associated to the demands of the marathon. So for well-trained athletes, all the way to elite and world-class athletes, the marathon is run at heavy intensity, so between pressure one and two, and we wanted to mimic the demands of a race. I think this is very important point, because previous research in other sports they've done something similar, but they've done it at lower intensity. And the physiological responses between moderate and heavy domain, they are quite distinctive. So if you see some effects at moderate intensity, that may not translate to heavy intensity necessarily. And then from the strength aspects, we've got like press. So that was done on a single leg. leg press inclined by 45 degrees with isometric calf raises. And that was done to look into more specifically about calf function and how effective athletes are in getting high forces and high power expressed pre to post training and then counter movement jump height and power. We've got Texas scans for body composition, which is the gold standard for body composition. So fat mass, fat free mass, and specifics fat mass and free mass for the lower limbs. And then we've also got MRI data from participants for muscle volume, but those are not included in the results of the study. We're still analyzing those data. So there'll be more to come on this, hopefully, in some time. You can see why the retention rate was so high. Like someone had been doing Dexter scans and looking at their, you know, bone density and then MRIs looking at their muscle volume and all that sort of stuff, looking at the followups to see if that's changed for, uh, you know, an elite athlete or a highly trained athlete. That'll be very interesting data. I know I'd love to go through that sort of test to get those sort of markers. Um, you're welcome to the UK. You're welcome. Yes. Very good. Um, very good. Also that you. mentioned the intensity on the treadmill and doing that for up to 90 minutes to try to mimic race pace conditions. It's a very smart way of going about it to then translate it into like a real world intensity to then get some really good buy-in or at least a lot of interest for the running community because people want to run marathons. They want to run half marathons. They want to run into those distances and whatever they can do at a better running. economy will obviously be very interesting to them. For those who aren't familiar, describing and determining running economy, to the best of my knowledge is, you know, how efficient can you run and utilize oxygen at a given speed? And so how would you calculate that? Do you have one of those fancy masks that works out the oxygen consumption during that heart intensity treadmill test? We wouldn't speak about efficiency just because technically speaking efficiency relates to work and that would be the ratio between internal work and external work. We cannot measure external work unless we have motion capture and forces, which is very hard to do. So in cycling it's much easier. have just like power on the pedal. In running it's not quite as direct. So that's why we call it economy. And as you were rightfully saying is the usually energy or oxygen cost of covering a given distance at given speed. So as a unit, we're about millilitres of oxygen per kilogram per kilometre per kilogram because it's standardised between people of different masses and per kilometre because it can help standardising for people that run at different speeds. So... that's slightly different than the unit used for Butamaks, which is millilitres per kilogram per minute, because you don't need that distance component. Butamaks just tells you the upper limit of your aerobic capacity. So, yeah, if we speak more specifically about energy cost and oxygen cost, the difference between the two is that energy cost accounts for changes in substitute utilization. So if you use more fat or carbohydrates that is accounted for, for energy, which is not usually accounted for, for oxygen. Okay. And you mentioned before that there was a control group and like intervention group. Can you talk us through those and what was actually involved in the intervention? Yes. Yeah. Uh, so we've got, uh, 38 participants in the start and then they were randomly assigned to either control or experimental group. The control group just kept doing the running exercise as they would usually do. So they were just instructed to keep running and training as they were used to. The strength group, they added two times a week of strength training for 10 weeks. So that includes plyometrics, vertical and horizontal, and maximal strength. And for the maximal strength exercises we've got single leg left press, half squats, like squats that would be aimed to reach parallel if possible, and isometric half raises. Okay. So twice a week, they would go through two plyometric exercises, one being a vertical, uh, jump of some description and one being a horizontal jump. Um, I know the, had the study in front of me before this recording, um, throughout that 10 week period, seemed that the vertical plyos went from Pogo jumps for the first three weeks to then progressing towards drop jumps. Is that right? Yeah. Yes. Can you just describe each of those exercises, the Pogo jumps and the drop jumps? Yep. So the Pogo jumps are just like hoping on the spot. And the idea is to maintain our contact time, which is somewhat below 200 milliseconds. That's what is usually suggested to have an effect, a positive effect of plyometric training on, on the body and muscle tendon units. So with Wix we initially just taught athletes how to do it and then they would be going on and on and maintaining that threshold and just aiming to go higher. So as long as they would be below the threshold they could aim to jump higher, which is kind of what I prescribed for athletes I work with as well in practice. And the important aspect is that they want to keep their knee, hip and ankle as stiff as possible to don't have any compliance and walk from the muscles, which we don't really want in that situation. And then from the drop jump perspective, it's basically the same but from a higher height. So you would step on a box, which I think it was 40 centimeters in the study, and you basically just step down and rebound with both feet. as high as you can. Okay. And then you're just jumping straight into the air and then back to the ground. You're not jumping back onto something. Yeah. You go down and then back up and then you can progress it farther with a jump onto something if you, if you want to. Yeah. Okay. Gotcha. So essentially, um, not jumping off a box, but just jumping from, uh, dropping off from a box, landing on the ground in a quick burst of movement, you're landing and then jumping as high as you can. in the air. So the first three weeks was the Poco jumps. I've got here three sets of 10 to 12. That would be for each side. And then once progressing to the drop jumps, they were doing three sets of six for those jumps. Yeah, that's right. Okay. And then we had the horizontal plyometrics. So rather than going vertical, we're now going horizontal and that progressed throughout the 10 week, starting with like a hop. hop and stick jump. you're sort of standing on one leg and then hopping as far as you can horizontally, and then trying to stick that landing. Am I fair with saying that? Yes. Okay. Um, after three weeks, they progressed to stiff leg bounds. I'm not entirely sure what that is. Would you mind describing it? Yeah. So you basically just, uh, keep your knee straight and you push forward with your ankles. So the idea is to push on the ground and, uh, move forward as much as you can by pushing with the foot on the ground, but without using the quads. it's a lot of, again, ankle work. And here, one of the hard bits is actually focusing on the pushing instead of focusing on bringing up the leg. So a lot of people flex their hip instead of pushing purposely on the ground, which is what we try to... tell athletes what I try to tell athletes when I work with them. And that kind of translates very well then to running and sprinting in general, because that would be what you want them to do when they are increasing their speed instead of increasing the straight length, working on improving their force on the ground to go faster. I might have to give that a try. like instead of In that first example where we're doing the hop and stick where we're just sticking the landing and stopping in one spot. Are they, cause we're going horizontally here. Are they just pushing off the ankle purely just using the ankle and just, um, continuously hopping, hopping, hopping along on a single leg? Uh, no, they alternate. So it'd be, how can I say that? It's yeah, something like somewhat like running, but with the knee blocked. So you have your ankles going like that. And then the better you get the farther you can go. Okay. It's, it's used quite extensively in athletics. At least I've done it a lot when I was still a competitive athlete. Yeah. Okay. So alternating from one side to the other. Okay. And then after week seven from week, weeks eight to 10, you progress that exercise to bounds for length. Can you describe the difference? Yeah. So that is more something like that'd be something that jumpers do more often, think, or power athletes do more often. And it's basically the same that you would see from a triple jump, for example. So you'd go from one leg to another and bounce between the two. So you don't have the landing of a triple jump and you just keep alternating between left and right. And here again, the idea is to give as much force as possible when you land. to then be able to have a higher flight time and go forward more. And there's also an aspect of like how much you drive forward and how much you drive up. But then, yeah, when you control that, then you can focus on pushing on the ground as much as possible. Gotcha. Okay. And so the hop and stick was three sets of six. The progressing to the stiff legged bounce was three sets of 10. progressing to those bounds for length was three sets of eight to 12. So they were the two plyometric exercises. And then you said there was three strength based ones being the back squat, the single leg press. And, uh, I think we mentioned the isometric calf raises. that right? Yeah. All right. Any specific instructions around the back squat? Um, they asked to go as deep as they could. They also had pins on the sides so that they could feel safe about doing it. think it took most of them less than two weeks to do an OK squat. And as you can see on the description, the load was initially kind of submaximal to then move towards 80 plus percent of an error M, one repetition max. We used the velocity to... to estimate that, so they have to be within a range of 0.35 to 0.5 meters per second as an average lifting speed, which is in the guidelines that we see for velocity-based training, a type of speed that should stimulate maximum strength. And yeah, as the week progresses, as weeks progresses, they... getting more more load and the tendency then is to do lower range of motion. So they were still asked to reach the physiological range of motion that they could reach. So I think that is quite an important aspect when we look into long-term adaptation and training for kind of complicated lifts or multi-joint lifts, which which lot of people may struggle with when you start loading them with loads which they may not feel fully comfortable with. That is what I've also seen with elite athletes, mainly with the squats because you can cheat the height. They tend to then reduce their own to still feel in control whether you want them to actually get close to their maximum capacity. There's always some buffer that... helps ensuring safety, but there's still that mental barrier of lifting heavy and going deep mainly for the squat or for lunges, for example, as exercises, which are not, uh, uh, use using a machine. Yeah. I think that's a point. And, um, I should probably mention those safety pins that you, uh, that you mentioned would be like, if someone was to look at. the uprights of like a squat rack or something, you can put pins in place so that it measures a certain depth. And if the bar goes below that depth, they sort of the pins catch the barbell so that if you so happen to not be able to make your way up, you can lower yourself as far down as possible. And those pins will catch the weight. Is that fair? Is that, is that what you mean by that? Yeah. Um, I should have also mentioned as well that within the population criteria, they, uh, needed to not. be experienced or had not done any strength training in the six months prior to the study. So you count them as, um, not too familiar with these particular exercises or not too familiar with the weights that they can lift and those sorts of things. Yeah, we, we wanted basically them not to be, uh, already adapted to the training because otherwise you would not see the effect of it. Uh, we said that six months criteria, but I would say for. The vast majority of them, they did not really ever engaged in strength training. And to be fair, a few of them, kept doing it after the training and they maintained it very happily through the running program. One of them, actually got to me, told me at the end of the whole program that if his approach to running was one of the... ways that changed his approach to sport in general. This strength intervention actually made a big difference in him to approach that aspect of exercise as well, which is I think quite powerful as an outcome. then if you think about the wider impact of not just the study outcomes, but on the habits of person thinking it is quite important to highlight that. Yeah. So weeks one to three, they were lifting like below 80 % of their one RM and they did three sets of six to eight. And then from after week three, they progressed to doing three sets of five to six. So they're reducing their rep range, but then increasing the weight to between 80 and 85 % of their one RM. And then. weeks, eight to 10, they're increasing the weights yet again, close to 85 to 90 % of their one RM, but reducing the reps yet again, to three sets of four to five with about a three minute rest in between those sets. You mentioned the tempo of the exercise. Can I just dive into that a little bit? The tempo that you're talking about to produce that the explosive movement, was that just to calculate their one RM percentage or like during those back squats were they instructed to try to complete the task, try to complete the squat at a certain tempo? Yeah, I think that is a good point and a very important aspect of in general strength training applied to Indian sports. We, they were instructed to produce the effort as quickly as they could. between the three exercises and that is one of the ways for which we can ensure that maximal strength adaptations are more effective. Basically, if we have a very high speed or maximal intent, we are more likely to recruit a larger pool of fibers, which then should lead to larger adaptations. If we maintain our controlled speed, we may not. activate quite as many fibers because that is related to the load based on Henneman's principle of the size of the muscle fiber basically. So yeah, I think it's quite important to highlight that and that's what I usually tell artists to do. Unless they are learning a movement, they are requested to be as explosive as they can in their efforts. Gotcha. The single leg press was the next strength based exercise, which I think we can quickly touch on because most people are familiar with a single leg press with a leg press machine and the sets reps, the weights were identical to the back squats. So I think we can move on unless there's anything you want to touch on about the single leg press. No, not really. They had a safety pin just for safety. And yeah, I think. That was one of the most remarkable improvements for some of the athletes. One athlete, I think, he improved by almost 65%. Wow. Yeah, he had a very low standard at the start. So if you look into the increase in body, in weight, it's probably similar to other athletes, but as a percentage, it was huge. And it was the capacity that improved the most from a strength perspective. probably because there's not a lot of technique. So you can kind of straight away focus on improving the strength instead of learning the movement first. Definitely. Yep. And encouraging for recreational runners who might be listening to this, who might be intimidated to do a back squat or something that involves free weights, single leg press machine, less intimidating and you can Like you say, there's, they've got those safety pins in place and not a lot of technique to focus on. So yeah, great tip there. Uh, the seated isometric calf raise. So, um, my, to my understanding, um, at the gym, there's like a seated calf raise machine where they've got the, the weighted pads as you sit at the sort of at your knees. then you can do a calf raise and lift the weights that are pressing into your knees. Um, and then they're just holding that. Isometrically. I got that exercise correct? So we, it was slightly different, both for the test, for the test we had our own custom built rig. And then for the training, we basically had an isometric rig, which is used for mid-type pool. So it's basically like a bar that is inserted into pins. And then when you do a mid-type pool, you just like. pull as you would do a deadlift, which in this case is the same but we would push through with the knee and the objective here was to increase the maximal force in an isometric way. That's because when we look into the behaviour of the calf muscle and the fascicles specifically, they tend to work very isometrically. in running, there's a lot of work that get taken off by the tendon, mainly the Achilles tendon. So even if you work isometrically, that still kind of resembles the demands of running. What I would do in practice is alternating between these aspects and the dynamic calf races. But I think it's quite effective even with high performing athletes having it isometric and requesting them to produce as much effort as possible without being able to move the bar. So if I imagine this correctly, someone's seated and they've got like a barbell almost across, just almost, or just above their knees. And when they do a calf raise and their knees kind of rise up and press into the bar, that bar doesn't go anywhere. And they're sort of pushing as hard as they can upwards as they go into a calf raise and they're holding that contraction to complete the exercise. Yeah, they were holding it for three seconds and then releasing for three seconds. A couple of other important points here. If you were to do it straight in a bubble, you wouldn't be able to, because there's a lot of pressure in a very concentrated area, which is the area of the bubble. So what we had was kind of a wooden piece that, wooden brace that we could... used to spread the pressure and it worked out very well for both the training and the testing. There's a figure of what that looks like and how the testing looks like in the supplemental material of our study. And you can do it basically anywhere. If you load, we would call it multi-power in Italian, I think it could be something like a Smith machine in English. It's basically like a squat rack, but you have guides and you can just bring the bubble down at the height that you want, load it up with a lot of weight so you can't move it and then have even like a 2.5 or 5 kilos plate on top of your thigh between your thigh and the bubble and then push through that and it works very well. I've done it a lot with triathlons I work with and they tend to be quite happy with that. Excellent. Yeah. I just scrolled down the paper. Um, there's 50 pages here. So there's a lot to scroll down, but I found the image there is very clearly depicting that exact exercise. So great for that. Um, all right. Let me see if I can, uh, now that I've lost where I was, let me go through the sets and reps. So the isometric calf raises, um, started off with four sets of six to eight. And like you say, they contract for three seconds, relax for three seconds and do that for six to eight. Um, and then as you progress, think we just progressed to five sets of four to six with a stronger contraction, hundred percent maximal, um, contraction. And that stayed the same throughout the 10 week duration. Um, excellent. And so let's dive into the results. Um, what did you find surprising and what are some key takeaways for recreational runners? Yeah, let's get that. Now we think we're discussing about results. I just remember that I kind of forgot one of the main parts of the design of the study. So we got this 90 minutes run, but then at the end we've got a time to exhaustion at 95 % view to max. So we wanted to look into a proxy of performance in a fatigue state. And we thought that that intensity would be kind of resembling our final kick of a race. As like athletes at the start, they would take between three and six minutes to do it, which is probably something similar to the last kilometer of a race. So that's how we designed it. And that was the aspect that more largely improved in the strength group. So pre to post training, we got a 35 % improvement in that variable. Now. I think it's important to highlight that 35 % improvement in time to exhaustion doesn't mean 35 % improvement in performance. They were probably translating anything between 7 to 10 % just because of how improvements in time to exhaustion then relate to improvements in time trial performance. So that is probably the most direct finding and most Yeah, easy way to test it yourself if you want to do it without any instrument. You can just like go on the same loop, do the same loop for 90 minutes and then do an effort at high intensity at the same absolute speed and see how long you last or just get like a kilometer or two and try to run it as fast as you can. you could potentially estimate how much, you would measure how much better you've got or how... much worse you've got depending on the training you've done. So that's for the performance bit at the end. And then for the aspects during the run, we've not seen improvements in economy at the start. So that was quite surprising. We can get maybe into the details of potential reasons for that later on. But that's kind of unusual based on the literature and based on what we said at the start that It's kind of known or we would expect improvements in economy in an unfatigued state. However, then we found an improvement in the fatigued running economy. So both within groups, so pre to post for the strength training group and between groups. So between the strength group and the control group, there was a positive effect of strength training in running economy durability. So running economy was better and, uh, uh, meaning lower cost towards the end of the trial between conditions. So control versus training and between, uh, pre to post training. So if I got this correct, so like a time to exhaustion would be at a very high intensity on a treadmill and just seeing how far you can go until you collapse the time to exhaustion. And when put through those particular conditions, pretty much just giving it your all that the people who did the strength interventions just lasted longer from like after that intervention, they could sustain that intensity for a longer period of time before essentially collapsing. Is that fair to say? Yes. Yeah, exactly. They lasted 35 % longer. And if you look into the individual responses, which are on the paper, there's only been one person that did not improve. And everybody else did get substantially better. Okay. And when we're talking about no changes in running economy, is that, um, that would still be at a race pace intensity. like the, how effective they are with utilizing their energy or utilizing their oxygen remained unchanged. Yes. So that's what happened at the start. So at 15, we got. two sub maximum intensities before starting 10 and 12 kilometers an hour, which were unchanged by the post. And we use the 15, 15 minutes time point as a way to look into economy at kind of race intensity that was also unchanged. then what changed was fatigue, the economy and fatigue state basically. Okay. So when they're particularly fresh, fresh legs, the economy how effective and efficient they were didn't really change. What's your thoughts around that? If you expected to see an improvement in their running economy, do you have any particular theories as to why? Yeah, it's hard. It's a hard one because that that was, if I were to, if I would have had to bet on something that it would have, the office would have improved except for the strength capacity would have been that because as we said, there's a lot of research. proving that. think maybe there's a couple of aspects that could somewhat explain that. We have a slightly older cohort than many other studies. The average age for the training group was, I think, 33 years old. And that may play kind of small part in that. They may have been training for several years already and therefore they're kind of room for adaptation on the economy was relatively small. And then the other aspect, which is also related to the room of adaptation for economies, that they were relatively decent athletes. The average 10 kilometers speed was, 10 kilometers pace, sorry, time was 39 minutes and a few seconds. Let's just say 39 minutes. which is probably better than most of other studies. So these two aspects could explain partially why we've not seen the improvements we would have expected. Gotcha. Yeah. That's pretty much the first thing I thought too, when you said that if we're looking at very highly trained males, they're probably very efficient already. They're probably very economical already, especially when they're in a fresh state. So potentially, yeah. wouldn't have much carryover. But that the next result that you're talking about was their improvement in their economy, when they entered a bit more of a fatigued state. Is that fair? Is that the other finding? Yes, correct. So they, this is how you define it. Their, their absolute consumption was reduced when they were fatigued. And the upward drift from unfatigued to fatigued was reduced as well. these two are kind of the two ways that at the moment are used to describe the durability and therefore the ability to maintain baseline physiology in a fatigue state. First, before the study, the change from fresh to fatigued in economy was 4.6%. So they worsened by 4.6 % in the strength training group. And then after the training, they only were by 2.1%. So they've got kind of 50 % better in that aspect. And if you think about running shoes and how they've been changing the kind of times and records in running in the recent years, they tend to give an amount of 3 to 4%. So that improvement in athletic state is 2.6%, which is Not too far from that three to 4 % range that we would get from the shoes in our first state. Yeah. I think that's very encouraging for someone who's like, like we say in this study, highly trained, um, to try to be squeezing out every little bit of improvement in their say marathon, um, performance to say, all right, how can I get better at when I'm really fatigued and how can I get better? when I'm absolutely maxing it out in the last, you know, 15, 10, five minutes of a marathon where I'm trying to push out every little bit that I have and I'm pushing myself to exhaustion. How can I do that? If someone was to try to improve those domains purely by running, it'd be, it'd be very, very hard to do and like increase your risk of injury. If you're having to try to supplement that with more running, more fatigued running, more, you know, exhausted running. you know, the risk of developing a running related injury is very high to try to achieve those gains. But if you can supplement it with 10 weeks of strength training twice a week and see those results, I think that's very promising and hard to say what they would have for other populations like the recreational athlete. You think that maybe their improvements in running economy would enhance even at lower intensities and those sorts of things. But what are your thoughts on other populations? Cause I know this was males. know this was highly trained. Um, you have any speculations around the female population or lesser trained individuals? Yeah. So I think, um, if we take a step back very briefly, I wouldn't define our group as highly trained per se. It's probably well trained, which is like a tire down. Uh, but if you look into some of the data that they've got from cycling, they found very similar results in elite cyclists. So these are actually out like professional cyclists and they've done 12 weeks of training for two times a week and they found basically what they found. So no changes in cycling efficiency in a fresh state improved after two to three hours of cycling at about 55, 50, 55 % of your max. And then a 7 % improvement in time trial over five minutes. So very similar results with. very high trained and kind of semi-professional professional tire athletes. When we look into female athletes, they've done already another study on female dual athletes, which included cycling and running as a test. And what they found there was the time trial, again, five minutes time trial on the bike and on the run was improved. in both. However, the economy didn't change in running and I think on top of my head got slightly better in cycling in a fatigue state. So kind of similar to our results, but no effect on the running economy from a running perspective there, which I think is just due to the fact that the intensity wasn't high enough. So they've been running at a very low speed, which probably didn't elicit enough. fatigue in that study, which is what we wanted to make sure about. So I wouldn't expect too much differences with female athletes based also on those results from this study. That's 2017 study from a group in Norway led by Bent Rønstedt, which was also the main author of the elite cyclist study I just mentioned. And they both did strength training for, I think, 10, 12 weeks. When we speak about female athletes, another aspect that probably is important to mention is that they seem to be slightly better in a fatigue state or in resisting fatigue. There's contrasting evidence, but there's very little evidence, so it's hard to say. But physiologically, there are reasons to expect females to be able to withstand fatigue better. So you will probably see smaller changes. throughout the run and therefore even the effect from a training perspective may be slightly smaller. On the other hand, when we speak about recreational athletes, because they need so little stimulus to get better, I think you'd see even larger effects. With those types of athletes, I'd be mostly concerned about running for that long at that intensity. I don't think that many people do that regularly. So running 90 plus minutes above the first threshold is something that basically if you can run those, then you are already getting into that trained tire of athletes. So I think that's something to highlight. There's a study that recently was done in Sweden, I think. I think they've done 60 minutes of running and then compared changes in economy and Viotomax pre to post with well-trained runners and untrained individuals. And what they found was that the untrained individuals had a very, basically much larger change, deterioration in both economy and Viotomax compared to the trained athletes. So I would expect that a training intervention to have better, effects than what we found. Appreciate you sharing those insights there for practically speaking, if a recreational runner is listening to this, and I think most that are listening to this already doing some form of strength training, just cause I've had so many episodes talking about the benefits. If they're doing their standard squat, deadlift, calf raises, lunges, and trying to improve their marathon performance, based on your understanding and based on the findings of this particular paper. What should they consider? What adjustments do they need to make? What tweaks in their training in their strength training should they consider to try to get better outcomes? Yeah. So when we designed this study, we wanted to make it in a way that it could be replicated kind of anywhere. So think taking the sample and, and just use it for, for yourself would work kind of fine. I wouldn't say it's the best way to approach strength training long-term or from a maximization of your time and opportunities perspective, because we've only had a very limited number of exercises which for the maximum strength side, for example, they were always repeated in the same way. So we would want to have some variety there, moving probably from the two-legged exercises to single-leg exercises. potentially having something stimulating a bit more the hamstrings and glutes. So deadlifts and step-ups are two of the ways that I usually stimulate those muscles. And then there's a whole focus on explosive exercises which we've not touched in the training. It wouldn't have just taken too long to move. between maximum strength to explosive exercises within 10 weeks, they would spend so much time learning the movements that you wouldn't actually have the time to then develop the skills, but usually you would go for explosive strength as well. So it could be jumps, box jumps, like deadlift jumps, counter movement jumps, squat jumps, and etc. So a lot of... explosive exercises that have yet another effect on the neuromuscular system, which are kind of closely resembling the demands of a race. So yeah, definitely having those in the program. And then there's another aspect which is related to the injury prevention side of it, which you as a physiotherapist can tell much more than me probably about. Yeah, I think some key takeaways would, um, that I would learn is like the tempo of the exercise as well, like trying to complete that, uh, heavy movement as quickly as possible, I think is a slight little adjustment that people may not be considering. Um, I think also when it comes to the sets and reps and weights and those sorts of sides of things, um, obviously being safe and obviously having safeguards in place, but the getting the results of this study was. lifting quite heavy by the end of that 10 week period. mean, you know, 85, 90 % of someone's one rep maximum is quite intense. And I think some people can be a bit complacent when it comes to strength training, doing their three sets of 10, it's feeling hard and then just never ever changing that for several months, I think is something that people can, you know, be reminded of that the progressive nature of things is what gets some good results as well. And then, yeah, obviously implementing maybe some of the plyometrics that were described in here, because I think there was some of those variations of some, some exercises ones that I haven't necessarily come across in the past. so, yeah, plenty of adjustments that people can learn from this particular paper. And I, know it's tough putting together such a design, getting a good group of people and seeing some, good results here. And so I want to thank you for taking the time and publishing this paper. Is there anything else on the horizon? Any other topics or ideas or things that are in the works that you're looking forward to? Yeah, as you were saying about the study, I think it's very important to highlight that the participants we had were very good. Like I was surprised about it and I thank them yet now because of that. Yeah, just amazing people that... I wouldn't have expected to stick so strictly to the plan. So we were lucky in that aspect and that is the main aspect of doing research, in my opinion, like being able to be lucky enough from some extent and being able to keep those like good people around to do research and give them something when you're done with the study. So yeah, still very happy about how that ended up as a project. And then for other projects that are on the way, as we said, there's like MRI data that we've got, and we will hopefully publish in the foreseeable future. We're working on the data still, so it'll be at least a few months. There's a couple of studies that are under review now, related to durability. So we've got the reliability study on our reliable leader-learning economy. and specifically over again like 90 minutes of exercise. Just a small spoiler, it is highly reliable, so that's a good thing for people that want to like track that aspect for longitudinal studies or for just like in longitudinal periods in general. And then we've got another one which again hopefully be out soon about how economy gets max and thresholds change acutely with a state at different time points during a high demanding run. Excellent. Well, thanks for your hard work and dedication. Very much helps me, my understanding of strength training and helping runners in general. And then obviously everyone who's listening to this, some, it's one reason why I want to get you on is because like you say, this paper is highly practical. It's, you know, anyone can just get a gym membership and start doing some of these exercises and they're not too complex. It's simple numbers. It's simple following the week by week stuff and getting some good results. so thanks for conducting these sort of studies. Thanks for coming onto the podcast here and sharing these insights. Thank you. And yeah, I look forward to hear from you again soon. If you are looking for more resources to run smarter, or you'd like to jump on a free 20 minute injury chat with me. then click on the resources link in the show notes. There you'll find a link to schedule a call plus free resources like my very popular injury prevention five day course. You'll also find the Run Smarter book and ways you can access my ever growing treasure trove of running research papers. Thanks once again for joining me and well done on prioritizing your running wisdom.