The Right Exercise Dosage for Tendinopathy Management

: today's episode, the right exercise dosage for tendinopathy management. Welcome to the podcast helping you overcome your proximal hamstring tendinopathy. This podcast is designed to help you understand this condition, learn the most effective evidence-based treatments and course, bust the widespread misconceptions. My name is Brody Sharp. I'm an online physiotherapist, recreational athlete, creator of the Run Smarter series, and a chronic proximal hamstring tendinopathy battler. Whether you are an athlete or not, this podcast will educate and empower you in taking the right steps to overcome this horrible condition. So let's give you the right knowledge along with practical takeaways in today's lesson. Welcome back. This episode is covering a research paper. This is actually going out on the Run Smarter podcast and also my second podcast, the PHT podcast, helping people learn more about and uncovering effective rehab strategies for proximal hamstring tendinopathy. And as I have been talking about, I've been diving a lot more into recent research, recent articles, both podcasts very nicely. So I thought it'd be nice just to record once and have both those episodes out there. The paper that we're going to discuss I have in front of me is titled, Effect of Resistance Exercise Dose Components for Tendinopathy Management. It is a systematic review and meta-analyses. And it was, I guess, published at the end of last year, so 2023. What they've done here with Usually with a systematic review is they get the recently published randomized controlled trials or whatever type of article or study designed that they want and they find a research topic or a question that they want to answer, go find all the papers that sort of cover that, bring it all together and see if they can come up with a general consensus, but with a meta analysis, they also take on the individual values of those designs and see if we can come up with like a mean or an effect, an effect size or how effective a certain treatment can be when looking at those individual numbers. So it's almost like rather than getting a whole bunch of papers and reading their results and kind of coming up with a general conclusion, they're actually getting the data, the actual numbers, the effect sizes and everything and putting it onto one graph, it's almost like combining everything and putting it into like a forest plot or, you know, having these tangible values and doing that across a whole bunch of papers. So they've done both of those things, the systematic review and the meta-analyses. So I'm going to cover the paper today and then I'm going to finish with a few of my thoughts on dosage. When we talk about dosage, we're essentially meaning the exercise sets, reps, rest periods, the weight, how heavy or how challenging or intense that exercise is, and also the frequency. So frequency meaning how many times during the week or how many times during the day, how often you're doing this particular exercise to help with your tendinopathy management. So a big question and yeah, a big topic. So the paper said like in the objective, was to investigate potential moderating effects of resistance exercise dose components, including the intensity, the volume, so sets and reps and frequency for the management of common tendinopathies. So using a bunch of different tendinopathies, in total they collected 110 studies, that 110 studies seemed to meet their inclusion criteria. And there was in total around close to 4,000 participants. And like I say, there was a range of tendinopathies. They used the five most common, which like would have been better if they included a whole bunch of just the lower limb tendons, but they included the rotator cuff, the Achilles, the tennis elbow, well, you know, the lateral elbow, so tennis elbow, the patella tendon, and also the gluteal tendon. So not proximal hamstring specifically, but the conclusions here, so just trying to cover the broadest range. It's like, okay, well, what are the five most common tendinopathies? Let's then scour the available research to come up with greater findings. And there's not a lot of studies done on proximal hamstring tendinopathy, especially when it comes to collecting a sample size and getting them to go through a set dosage. Tons on Achilles. tons on rotator cuff and so yeah can just gather more data that way. I thought I'd start off with the introduction just to sort of lay out the scene. So within the introduction of this paper they say tendinopathy is a prevalent condition involving degenerative changes within the tendon in both children and adults commonly in the Achilles, rotator cuff, lateral elbow, patella, and hip tendons. It affects athletic and non-athletic populations and can manifest in persistent pain, swelling, loss of function, and diminished movement. I don't really think swelling would be that common. I think tendon thickening is quite a common presentation. Maybe in the very acute setting, maybe swelling is there, but definitely persistent pain, definitely loss of function, and sometimes diminished movement. They continue, exercise therapy is the mainstay of conservative management and has focused largely on resistance exercise, often eccentric actions, to encourage load tolerance leading to structural adaptations at the muscular tenderness unit and functional restoration. You might've listened or you may not have listened to my previous conversation with Miles Murphy talking about tendon management. He's done a lot of work in the Achilles tendon. And yeah, sort of fits this pattern of saying, okay, a lot of conservative management is revolved around resistance exercise and encouraged to build up the load tolerance of that tendon and the structure around it so that it can adapt and build up its level of capacity to reach what is functional for you. So that's essentially what they're saying. It continues, at the most basic level of clinical settings, exercise dose comprises of three variables, the intensity, the volume and frequency, with overall exercise dose quantified as the product of all three. So saying the dose just means all three of those variables. It has been recommended that primary studies and evidence synthesis attempt to better quantify the dose response relationships. So trying to find the answer. What is the best? dose response. And Miles Murphy did mention in our conversation that it is a lot to do with science, but then a lot to do with a bit of an art, because we don't have the numbers. We can't say this everyone with Achilles tendonopathy needs to do this exercise, these sets, reps and dosage, because everyone's different. Everyone has different levels of irritability, sensitivity, different goals. And so you know, that's where the art comes in, trying to tweak things here and there, but can we come up with a better default, a better direction of our starting point? They say the present systematic review with the meta-analysis combines data from studies investigating the effectiveness of resistance exercise across the most prevalent tendinopathies. The aim was to investigate potential moderating effects of resistance exercise dose components, including intensity, volume, frequency, Three. Contemporary meta analysis and meta regression approaches. Okay, the participants. So within, they need to kind of have a inclusion criteria within this paper. They need to scour through other papers and say, all right, is this relevant to our hypothesis? Is this relevant to our particular question that we want to answer? So we need to try to find out what population fits. They decided to include people of any age or gender with a diagnosis of shoulder pain. They said it's for the shoulder, it was rotator cuff type of pain, lateral elbow, patella, Achilles or gluteal tendinopathy of any severity or duration. So if you've had an Achilles tendinopathy for two days, or if you've had it for two years, it would still be included if they had a diagnosis of that tendinopathy. full thickness or large tears were excluded. And so another important characteristic. They said that in the outcomes that they wanted to include, so now that they have the population, they wanted to compare it to say, okay, obviously want to see what dosage gets people better, but what is better? They said it needs to cover in terms of an outcome measure, one of six domains, two function, three pain, four range of movement, five functional capacity, and six quality of life. I would say that's a fair good list because someone, especially with tendinopathy, someone can have the same level of pain, but their level of function can improve significantly. As an extreme example, you can say, you can only tolerate, say, 500 meters of running and have a two out of 10 pain and then continue progressing where you still remain at a two out of 10 pain But can run a marathon that is a good example of pain hasn't really improved but quality of life functional capacity function disability all of those things are improving so Yeah, good thing that we're covering all these bases Just because I'm interested in these numbers in terms of what's included within this search criteria. So you put some questions out there, you go to all the databases and you see how much things you've returned. So you come out with a whole bunch of key terms and they came back with a total of 12,379 potential studies to be included. Then they remove all the duplicates because they searched multiple databases and still have 6,944. And after going through that, well, they have to go through, now that they've removed all the duplicates, they have to quickly scan and read the titles and abstracts of nearly 7,000 papers and see what's relevant and what isn't. And after doing that particular screening, they're left with 440 studies, and then they have to go through those 440 studies and read through the full text to then see, okay, is this worth being included? And once they did that, they removed a further 330 and so was left with 110 studies comprising of 148 treatments or treatment arms and like I said at the start, almost 4,000 participants to then be included in the meta analysis in the certain graphs, in the charts, in the forest plots to see how effective these treatments are. If you're interested, 32. of these treatments were involved with the rotator cuff. 29% involved the Achilles. There was 20% when it came to the lateral elbow. 16% was the patella and only 3% included gluteal tendinopathies. The overall design or approaches, treatment approaches, there was 60% eight treatment arms for eccentrics only. There was 55 treatment arms for concentric versus eccentric and then 16 treatment arms looking at isometrics only. So the eccentric would be an exercise loading up the tendon while that tendon is lengthening or the tendon muscular unit is lengthening. Concentric is when it's shortening. And so eccentrics have been very popular in tendinopathies for the last. You know, several decades as miles Murphy did mention on the podcast, a lot, there was a lot of attention around eccentric and how effective they, they are. Uh, but recently there's been a shift in that concentrics are just as good in terms of improving pain, but the concentrics almost a favorable because. It restores function a bit more. He used the Achilles as an example. He said that, okay. People do eccentrics for their Achilles where they start at the top of a calf raise and then they load up their affected side and they're slowly dropping their heel down towards the floor. So lengthening that Achilles and calf, under load. And then when you get to the bottom, you unload it, i.e. shifting your weight to the other side, go back up to the top. So it's been unloaded all the way up to the top and then we load it again to come back down. That's an example. And that has been a good job in terms of improving pain and helping people get better. But as Miles said, when you look at their function, i.e. how many car phrases they can do, they go through this eccentric program and they feel a lot better. But then you get them to do the same amount of car phrases and they haven't improved their strength in terms of functioning, in terms of car phrases. And so concentrics will do that. And so. I think I've mentioned in the past, what I tend to do if someone is, does have a quite a grumbly really irritated tendon. I'll start just with eccentrics to calm things down, but concentrics have to be eventually integrated in at some stage, whether it's at the start or halfway through the middle, that's to restore that function is really important. But then there was also some isometrics included in this study, which is just holding that position. So as an example, we go back to that calf raise, sort of finding the midpoint of a calf raise, loading up that tendon and just holding that position would be an isometric example. Okay. For the results, let's look at the sort of broken it up into intensity and then the frequency and then the volume. So we'll go through all of those and then we'll come back and tie it up into a nice little bow. The intensity. So the intensity is like, you can consider the weight. How heavy are we when we do these exercises? Of the 148 treatment arms that included the intensity, no, out of the 148 treatments overall that included, 123 involved the category of intensity. They categorized them as lower intensity would be body weight exercises. or higher intensity, which would be additional external resistance. So this is very hard to categorize when talking about different tendons within the body and, you know, what is heavy, what is light. So they've done a very good job and a very simplistic job of saying lower intensity is just doing body weight exercises. Higher intensity is adding in some additional resistance. The Meta regressions provided consistent evidence of greater pulled mean effect sizes for increased training intensity. Meaning better than or higher than, more intense than body weight exercises seemed to have a greater mean effect in terms of improvement. So that was the intensity. The frequency of the exercise, so how often people are doing these exercises. 135 articles or treatment arms included this information about how frequently they're doing these exercises. And they categorized it into low frequency was less than daily, moderate frequency was daily and then high frequency was more than once per day. So it's pretty high. I would say like if you're at low frequency You're probably doing an exercise every second day, or maybe as much as like three times per week would be a low frequency. But then we have, I guess your moderate frequency is your daily exercises, and then anything that's higher or lower than that would be those other two categories. Consistent evidence of a moderate effect was also identified with resistance frequency, with greater pooled mean effect sizes identified with the lowest frequency. of less than once per day. So doing exercises, doing these exercises, less often provided greater treatment effects. They also said that consistent evidence of this mean effect size with doing it less than once per day was also obtained when the analysis separated out the tendinopathy locations. So yes, come when you're considering all of them as like a blanket statement. less frequent is more effective. But then when you isolate them all out to different tendencies, also less frequent was more effective. Let's talk about exercise volume. So the exercise volume was categorized in terms of the number of sets and repetitions for the particular exercise. They said that the most common number of total repetitions was 45. So the most common exercise dosage when considering all of these tendinopathies was three sets of 15. So if you're doing three sets of 15, that's 45 in total. Therefore, they decided to account for sectioning this off. They said that the training volume was coded as a binary variable, consisted as lower volume or higher volume. So the lower volume was anything less than 45 repetitions. The higher volume was anything greater. than 45 repetitions. And so they say, while the median point estimates from the primary meta-analysis favored lower volume exercise, this ordering was not consistently maintained when meta-analysis was separated for tendonopathy locations. So generally blanket statement, it seemed that lower volume exercise, so doing something fewer, lesser than 45 repetitions seemed to be a good approach. But when separating out for the tendinopathies, I think in particular with the shoulder, it didn't really stack up. So potentially, like the shoulder based rotator cuff exercises, maybe doing more repetitions than 45, three sets of 15 was favourable. We've done all those results. We're gonna get to the discussion, sort of summarize this all and see where we can take it. And then I'm gonna share my insights at the end. So the discussion says, our review provides the latest synthesis of training dosage in resistance exercise therapy for tendinopathy management to date. Despite the extensive variability of therapies, some general patterns were identified, indicating that increased loading with greater time for recovery, may propose superior results. So when they're talking about the loading and the frequency, they sort of seem to say, okay, doing things heavier with fewer reps and doing it less often, like would subject the body to, or subject the tendon to higher loads, increased loading, with also greater time for recovery, because the tendon requires adaptation. And the adaptation doesn't come when you do the exercise. It comes with after you do the exercise, once you've had adequate recovery. So it seems like these things are, these variables like adjusting these things seem to fit that adaptation response a bit more. They say the meta regression consistently identified greater effect size estimates for therapies employing higher intensity exercise. through the addition of external loads compared to body mass only. Similarly, they found that there was a greater effect size for therapies involving a lower frequency compared to a higher frequency that were also likely to comprise of reduced loading to enable recovery. Less consistent results were obtained for moderating the exercise volume. They're always a bit repetitive when they talk about this stuff, but they say in our review, Consistent evidence was obtained indicating that performing resistance exercises less frequently throughout the week in brackets less than once per day was more effective compared to once per day or greater. To achieve musculotendinous unit hypertrophy with resistance exercises requires higher levels of activation. Taking into consideration the microtrauma caused by resistance exercise in the tendon tissue. with this would be optimized with adequate rest periods between sessions, allowing for greater recovery times between sessions to play a role in effectiveness of the intervention. Comparisons of exercise volume commonly reported as the product of sets and repetitions did not produce consistent results in our review. However, it is worth noting that the meta regressions investigating volume for shoulder tendinopathies provided some evidence of increased effectiveness of higher volume exercise for both outcome domains producing large and small effect sizes. Tendons of the shoulder facilitate repetitive movements of daily tasks with less load than larger weight-bearing tendons like the Achilles and may require programs that imitate the repetitive nature through higher volume of exercise. So this is sort of what I was getting to at the start. Different tendons are, and it should be treated differently. Like I said, this would be a great paper if they only included lower limb tendons because lower limb tendons are weight bearing tendons. They load with body weight and throughout the day, your Achilles, your patella, your glute, your hamstring, like they have a different kind of makeup. Yes, they're all tendons, but they serve different purposes. And as this paper describes, like the tendons of the shoulder are required for low load, high repetition, just constantly like doing tasks, low light tasks throughout the day, and that's what they've adapted for. And so when it comes to a treatment dosage, sure, it makes sense that a higher repetition, lighter weight maybe is an effective. approach and sort of skews when it comes to the volume. But for Achilles stuff, maybe the lower volume would be more advantageous. So obviously some limitations. Let's wrap up the conclusions for this paper. They say that clinicians should consider prescribing higher intensity, higher intensities of resistance exercise through the application of external loads, rather than just body mass. And given the increased load prescribed lower frequencies of sessions to allow for adequate recovery. Further refinement of the interrelationships between exercise dose parameters and patient characteristics are required, including better understanding of the influence of exercise volume. So that's sort of where the art comes in, making slight adjustments here and there to allow for the type of tendon, but also the type of patient and who's in front of you. So just to final word for clinicians, but I know not a lot of clinicians listen to this. I'm glad they kind of mentioned this as an overall message in the paper because so many times I, I jump on calls with people who have high hamstring tendinopathy or have Achilles tendinopathy and you have a chat with them and they've seen a physio and you go through their exercises and they've just been doing body weight exercises for three months and not really getting better. They're doing bodyweight bridges or bodyweight calf raises or bodyweight eccentric calf raises and may have seen some improvement initially, but just haven't, uh, you know, had that same ongoing improvement. They reach a plateau and they're just the same. And it's not until you apply some loads that they continue to see those improvements. So I have a few final words here. Uh, When it comes to picking your patient and picking or decision making for you if you are injured with a tendinopathy, we want to see what stage of your rehab you are. This is just my personal preference. So initially, if someone is quite irritated, has a quite irritable tendon, high level of pain, that pain persists for a long period of time. I usually like to start off with the little and often approach. We can't give this person like high resistance, higher exercises. Sometimes they can only tolerate body weight exercises based on pain. And it would be irresponsible to say that this paper said, start lifting heavier, do it less often. But when you start lifting heavier increases pain and irritates the tendon for days. So in this particular case, we would say, all right, let's do a little and often approach until things settle down. Because we wanna do some loading, we don't wanna completely rest because that just fosters weakness. So let's try to see how much we can lift. Let's try to find the maximum amount you can lift, but because it's so irritated, ends up being quite light anyway. And because it's quite light, we don't require as much rest for the adaptation response. Sometimes, It doesn't trigger any adaptation response. Sometimes it just triggers an analgesic effect just to help calm down symptoms. So this little and often could be body weight, but it also could be like light loads, light external loads, but we can do it quite often because it is light. So it could be once or twice a day or multiple times throughout the day. Only for people that are really irritated. Some people I start working together and it might be painful, but it's not irritable. like irritability would be if we were to overload you, how long does it stay irritated for? Because we could do one set of 10 for an exercise that's too much and it sets someone off for three days. It's very highly, a highly irritable tendon. If someone's like a low irritability tendon, they could do one set of 10 and it's overloaded them, but they're sore for 30 minutes and then they're fine. And so it's low irritability. So if someone's really irritated, let's do the little and often, but eventually we wanna progress. We wanna progress once you're ready to do so towards the heavy. We wanna progress the weight, not necessarily the sets and reps, we wanna keep the rep range. We could do around three sets of 10 as very generic, but when you're ready to progress, we can't just continue doing something three times a day if... the weights continue to pile on. So this is where the judgment comes in, a little bit of a fine art or a little bit of experience to say, okay, now you're ready to back things off. Let's go away from the little and often. Because you're getting slightly heavier, let's just do it once a day. You know, if we're doing bodyweight bridges three times a day and we decide to add load, maybe we're adding 10 kilograms to the hip when we do this glute bridge. Okay, let's do that now once a day. then when we progress away from bridges and do something like a deadlift, okay, let's do that once every second day. And so we're slowly getting heavier and heavier and more challenging, but backing off the frequency so that eventually at like the end stage rehab, you're doing really heavy stuff, you know, 150 pound deadlifts, but only doing that twice a week. That's where we sort of dosage that's good for tendons, but also good for strength, general strength, for general performance where we've hit that sweet spot. And obviously we'd let symptoms be our guide of when that time is right to progress, when that time is right to back off the frequency. Often people are not really interpreting their symptoms because, or not interpreting their they're progressing their exercises, but keeping the frequency the same. So they're still doing their exercises once a day, but they're doing really challenging exercises now, and they're just really sore. They're sore for the rest of their body. Their tendons constantly sore. And sometimes when I jump on chats with people, I instantly pick this up and be like, how about we do this less often? And then all of a sudden they feel a lot better just because they haven't picked up on that particular pattern. But if you are a... person who does have a tendinopathy and does like load often throughout the week, a lot of times this loading can create an analgesic effect and people can feel a lot better throughout the day with sitting, walking, driving, doing their running, all that sort of stuff once they've loaded up their tendon. So this comes to like a bit of a sticking point of, okay, well I feel better every day that I load my tendon I feel better, but now you're telling me to back off the frequency. where's the balance there? And we can load daily, but still have the right balance of recovery because we need recovery to adapt. So I got this from the Tom Goom paper on managing proximal hamstring tendinopathy. He suggests, and this isn't for everyone, I only suggest this for maybe like 15% of my clients because they do have this good analgesic effect because they are at the stage where they are lifting really heavy and you know, it sort of fits within their schedule doing a high day or a heavy day, followed by a low day followed by a moderate day followed by a rest day. So we go high, low, moderate rest, high, low, moderate rest, high, low, moderate rest and you are loading up your tendon, you know, five, six times a week. But having the right ebbs and flows so that the tendon and the body do get the adequate recovery with the adequate stimulus, the adequate heavy load that tendons love. Tendons love slow, heavy, progressive load. And so that's how we can meet that. And so that might be something that you can try if you find that you're struggling with the frequency of loading, progressions of exercise, and just how often we're loading things. So that's my final thoughts. I think this is a nice paper. This paper is an open source paper. Like I say, the title, let me scroll back up. The title is, Effect of Resistance Exercise Dose Components for Tendonopathy Management. I always say this like these titles also very long, very wordy, very complex, but I can include it in the links of the show notes and you can go check it out. I've only just read maybe about, I don't know, 25% of. what's included within the paper. So if you want to go check it out and learn more, you can obviously do that. Um, and yeah, uh, happy to deliver whenever new research comes out. It will be. If it's relevant, if it's interesting, if it's changing the way I'm thinking about management, and I think you will learn from it, I'm going to release it on the podcast, so stay tuned and yeah, enjoy your week, enjoy. Well, if you are rehabbing a particular tendon, hopefully some Slight adjustments in this podcast can help you with your management and we'll catch you in the next episode. towards an empowering, pain-free future. And remember, knowledge is power.