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Proximal Hamstring Tendinopathy is a horrible condition affecting athletes and non-athletes alike. If you fall victim to the misguided information that is circulating the internet, symptoms can persist for months, sometimes years and start impacting your everyday life.
This podcast is for those looking for clear, evidence-based guidance to overcome Proximal Hamstring Tendinopathy. Hosted by Brodie Sharpe, an experienced physiotherapist and content creator, this podcast aims to provide you with the clarity & control you desperately need.
Each episode brings you one step closer to finally overcoming your proximal hamstring tendinopathy. With solo episodes by Brodie, success stories from past sufferers and professional interviews from physiotherapists, coaches, researchers and other health professionals so you get world class content.
Tune in from episode #1 to reap the full benefits and let's get your rehabilitation back on track!
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On today's episode, we're diving into the latest research on collagen supplementation for tendon health. Welcome to the podcast that gives you the most up-to-date evidence-based information on PHT rehab. My name is Brodie. I am an online physio, but I've also managed to overcome my own battle with PHT in the past. And now I've made it my mission to give you all the resources you need to overcome this condition yourself. So with that, let's dive into today's episode. I am really excited about this new paper that I've just stumbled across. It was released this year, so 2026, a couple of months ago. And the title of this paper is Collagen Supplementation on Tendon-Related Structural and Performance Outcomes, a systematic review. And I thought extremely relevant if you have a tendinopathy, you're looking to rehab effectively, or you are just wanting to... or you maybe have had a tendinopathy in the past and you're wanting to reduce your risk of it coming back. Or if you just want to focus on performance, because this does cover analyzing physical performance in that sense as well. And I get asked about collagen supplementation a lot. And it's something that in the literature, it's been hard to piece together, I guess, prior to this release of this paper. prior understanding is like, okay, some health professionals swear by it, I haven't come across a lot of compelling research to say yes, definitely do it very hard from a day to day uh case study. People say, yeah, take the college and I think it's making a difference. uh I take college in as well. And like, it's very hard when you take any kind of supplements to notice real, tangible differences. So from a person to person, case study basis, very hard to judge. um And yeah, basically, some of the other health researchers, like if I can't find really compelling evidence, I fall back to the health professionals and researchers that I listen to on podcasts or YouTube and the ones that I trust. And half of them say, yeah, it's great, definitely take it. Very advantageous. And the others kind of say, well, You know, collagen is just a protein that is, you know, ingested, it gets digested and ah whittles down into its individual amino acids anyway before it crosses the blood brain barrier. Because I guess the thinking being when it comes to tendons and tendon related health, 70 % of a tendon, it varies from tendon to tendon, but for the majority, the vast majority of the matrix or components that make up a tendon is collagen. And so if we consume collagen, does that mean that it directly translates into helping tendons heal and adapt to get stronger? Hard to say. um We do know that amino acids, like when you digest proteins, they break down, the stomach breaks it down into its individual amino acids. and then gets absorbed into the blood where once it's cross that barrier, it then can start reorganizing itself into different proteins like collagen to be used where the body needs it. But it's from that point on that it can turn into any type of uh protein. so yeah, the half of the experts I listened to say, you know, you could just, as long as your protein intake, And you've got it as long as your protein consumption is adequate and you've got the right amount of quality or the right amount of essential amino acids required for the building blocks of the body. It doesn't matter in what form you consume it because it's going to be digested and broken down into amino acids anyway. ah And so that's where I've been left puzzled. And, um you know, when asked about collagen supplementation, I haven't been that definitive. I guess after this paper, my opinions aren't still yet definitive, but I'm leaning more towards um better advice. And so we're gonna cover this paper today. I guess my other prior knowledge and understanding is referring back to the advice from Keith Barr. I know a lot of people have listened to that particular episode and his understanding of tendons and tendon healing and how the tendon adapts and his particular protocol. which I'll pull it up now. I've had a previous paper that I've referred to a couple of times. The title is Stress, Relaxation and Targeted Nutrition to Treat Patellar Tendinopathy. This is a case study where they had a NBA player, a very severe patellar tendinopathy that they loaded with a specific loading protocol, but also with a nutrition intervention. So one hour before doing loaded exercises, this athlete would consume 15 grams of gelatin, which is like a collagen based gel and around about 225 milligrams of vitamin C, which I think they just mixed the gelatin into 16 ounces of orange juice, which naturally contains the vitamin C. And like I said, timely, so 60 minutes before doing the workout. So based on Keith Barr's understanding of tendons, that's the intervention that he stuck to and that's something that I would advise patients on. This isn't scientific enough, but this is what the experts are doing and you can follow that if you like. And so again, that's setting the stage of my prior knowledge before reading this particular paper. So like I said, the title, collagen supplementation on tendon related structural and performance outcomes. This is a systematic review. They are trying to analyze and assess. what the available literature is on this particular topic and simmering it all down to come up with some conclusions. And while the number of papers that they found, the quality of the papers that they found and the sample sizes within these studies are not extremely robust, it does help us bring some understanding to our current level of knowledge where we, our current understanding for collagen supplementation. And like I say, it sort of helps point us in the right direction. So let's set the stage with the introduction, and then we'll go into the methods and exactly what they've found and how it matters to you. So let's set the stage. They say, predominantly composed of type one collagen, tendons adapt structurally and functionally to mechanical loading through increases in cross-sectional area, stiffness, extracellular matrix organization, which collectively enhance force transmission efficiency and injury resilience. Just saying that the tendon itself needs some sort of mechanical loading, not complete rest, some sort of mechanical loading, enough mechanical loading, i.e. strengthening exercises to adapt and be a better tendon. And it does that by increasing its size, by increasing its stiffness and organizing the cellular matrix in a way that makes it. better at transmitting force, you could say. Collagen supplementation has emerged as a promising adjunct to mechanical loading for promoting tendon remodeling. Hydrolyzed collagen and collagen peptides contain high concentrations of, and they talk about all these different amino acids, glycine, proline, hydroxyproline, hydroxylysine, and these are amino acids critical as biochemical precursors to collagen synthesis. These are the breakdown of the different amino acids within collagen that make up the building blocks so that the tendon itself can adapt what we call collagen synthesis or tendon synthesis. When co-ingested with vitamin C, an essential co-factor for cross-linking collagen, these amino acids reach peak serum concentrations approximately 60 minutes post ingestion, ensuring their availability during the period of enhanced collagen synthesis stimulated by mechanical loading. This synergy suggests a potential optimization of exercise driven remodeling through strategic nutrient timing. So what they're saying here is like when you ingest collagen in the mixture with vitamin C, the combination of these two things help uh promote these amino acids to the right areas, I guess you could say. And in terms of timing, once you ingest these foods, it takes about 60 minutes for them to become more available, like the peak availability. And so that's when we need to load attendance. Let's ride that wave optimizing that timing. And so we're synergizing the mechanical loading that's required with the building blocks that are required with the vitamin C that helps direct things to the right area and sort of enhance that whole synthesizing process. Although collagen supplementation has traditionally been investigated for its effects on joint pain and cartilage health, there is emerging research towards its potential role in enhancing tendon and muscle adaptation when combined with resistance training. However, findings from trials remain mixed. While some report improvements in tendon cross-sectional area and stiffness, others show minimal effects on muscle strength, hypertrophy and performance. This inconsistency highlights the lack of clearly defined evidence-based guidelines regarding optimal collagen supplementation protocols in both clinical rehabilitation and athletic performance settings. Therefore, the purpose of this systematic review is to critically evaluate the effects of collagen supplementation alone or in combination with vitamin C on tendon related structural and performance outcomes, including tendon cross-sectional area, stiffness, muscle strength, muscle cross-sectional area, and physical performance. By synthesizing the available evidence, this review aims to clarify optimal dosage, timing, and implementation strategies to inform evidence-based application. in the clinical rehabilitation and athletic performance settings. So a huge undertaking to see if they can simmer down and come up with, okay, this is what the evidence shows, this is how effective it is. And if it is effective, this is how much you should take and at what duration or like what how we should be timing it. And so their eligibility criteria is quite vast, I guess you could say. But, know, cast a wide net and just see what you can catch. The inclusion criteria, exclusion criteria, I'll go through a bit now just so you can understand the magnitude of this. The population uh that they chose were just humans, any age, any gender, any ethnicity, participants with healthy tendons or pathological tendons. In terms of the intervention, they had to have some sort of collagen supplementation that includes hydrolyzed collagen, gelatin, or collagen peptides. studies had to include a proline or glycine as part of the supplementation regime. So they're just amino acids that are a part of collagen, as I mentioned before. uh What are they comparing it against? So the intervention group needed to be consuming some sort of collagen. Studies can include a control group, either receiving a placebo or no treatment whatsoever. So taking some sort of mixture or fluid or tablet or whatever that sort of mimics what collagen is, but it's just complete placebo or just taking nothing at all. And studies comparing different types of collagen supplementation. They excluded studies without a control group or appropriate comparison groups. And in terms of outcomes, this is where it does get quite vast. Studies reporting on tendon health outcomes needed to include, but not limited to, the tendon structure, tendon mechanical properties, muscle performance, physical performance, pain levels associated with tendon injuries. So there's a lot of outcomes to look for and see if any of these studies that they find contain those. Um, so like I said, casting a wide net, I would call. and so how many did they find? They submitted all down, doing all their searches came up with, um, the round one, 887, uh, they removed duplicates. then looked at looking at the titles and abstracts and seeing if anything could be included. Uh, they look through that, similar things down to about 27 papers. then they did the full text, not just going over the title and abstract, but then looking at the full text of these 27 papers, and then excluded a whole bunch that did meet their inclusion criteria. And they were left with eight, eight papers, like I say, it's not a lot, not a lot of robust things that were going off here, but just goes to show you how little data there is on collagen supplementation for this particular. answering this particular question, trying to come up with real relevant practical protocols for this sort of thing. And within these studies, you know, sample sizes are quite small. But nonetheless, we press on what did they find? So in terms of the results, I'll go through the results. uh And then the discussion, which I repeat myself a little bit, but under a slight different context. So when it comes to the collagen, ingestion. So collagen supplementation protocols varied. I should probably start by saying this. When I talk about the results, the results will vary quite a lot. You might say, oh, this is really promising. Oh, that's a bit disappointing that the other studies didn't find too much. But maybe within that study, maybe they only did the intervention for four weeks as opposed to the other one that did their intervention for 12 weeks. Or maybe they only ingested five grams of collagen where another study ingested maybe 30 grams of collagen, or maybe their strengthening protocols were different. This is where so many different variations come into it that different studies produce different results. So just bear that in mind as I go through these results. So collagen supplementation protocols varied in both dosage, frequency and type among the eight included studies. Two studies employed higher dosages of 30 grams One study used a dose of 20 grams and three studies administered 15 grams. Two studies used five grams. The ingestion frequency also differed. Five studies administered daily, so uh seven days per week. Two studies following three days per week protocol and in one study implemented a twice weekly regime. Three types of collagen were observed, hydrolyzed collagen, collagen peptides and a combination of hydrolyzed collagen with vitamin C. When it came to the training protocol, which this is a important element to discuss, all of these things had to have some sort of strength training involved. And when you are doing some sort of collagen supplementation, that does need to have the training stimulus. You can't just simply take collagen and expect your tendinopathy to get better. It has to be matched and timed appropriately with the right amount of training that then stimulates the tendon to adapt. So it needs both of those ingredients. So the paper said that these training interventions varied, again, similar to like the ingestion, varied quite a lot in duration, type, weekly frequency, among the eight studies that included. Five studies. had traditional resistance training protocols with durations ranging from 12 to 15 weeks. think 12 to 15 weeks would be pretty acceptable. One study combined resistance training with a sport specific match day, that was 10 weeks, while another employed, I guess the plyometric and power-based outcomes that some of these papers included were very short. Four weeks for the power-based training protocol. and the plyometric specific intervention was another four weeks. The training frequency varied, five studies utilized training three days per week, and one study implemented two days per week, and one study utilized a five day training protocol, five day per week training protocol. So all these varied quite a lot. If you do want access to this paper, it is part of the Run Smarter database that you can sign up for. and you can have a look at the images because there are eight studies here that can come up with some nice graphics and illustrations to be like, these are the studies that are included. This is the duration of the amount of weeks and what outcome was included can give you a nice picture. Okay, what do they find in terms of tendon cross-sectional area as an indication of uh if the tendon is getting bigger through strength training, we can imagine that that's helping overall helping the tendon. So four studies evaluated the effect of collagen supplementation on tendon total surface area or cross sectional area. Studies by Jega and Nalty, their two individual papers, actually the Jega author had two different papers and the Nalty one had one paper so they're talking about three papers here. Demonstrated cross, demonstrated increases in cross-sectional area, favouring the collagen supplementation groups. In one of these Jega studies, a 14-week resistance training program combined with specific collagen peptides led to a almost 10 % increase in Achilles tendon cross-sectional area. So it was 9.8 % and compare that to about 4 % increase in the placebo group. So we'd expect some cross-sectional area improvement in the placebo group because they are still doing strength training. But it seems like the cross-sectional area improved from 4 % to almost 10 % when a certain group included added in the collagen supplementation. In a similar fashion, the other Jega study found that there was a 10 % increase in patella tendon cross-sectional area in the collagen group versus 6.5 % in the placebo group. with significant effects observed at multiple tendon regions. The other study, the NALTI study implemented a 12 week lower extremity resistance training program combined with 30 grams of hydrolyzed collagen and 50 milligrams of vitamin C, which resulted in a 6 % increase in patella cross-sectional area compared to no change in the placebo group. So again, seems to be quite a substantial difference in the intervention group compared to the placebo group. But conversely, there was a Lee paper who reported no significant differences between groups in cross-sectional area following training with changes of 1 % in the collagen group, well, 1.07 % and 1.1 % in the placebo group. So out of these four studies that looked at the collagen effects in cross sectional area, tendon cross sectional area, three out of the four came up with some positive findings and one uh no difference. Let me just have a look at the Lee study. The Lee study was 10 weeks and that involved the resistance training and match, match day, match performances, whatever sport that was, I think it was soccer. Okay, but this is just one of the outcomes, cross sectional area and Someone argue, I don't know, that improve? Does that help my tendon pain if I'm in rehab? Does it um help reduce my risk of injury if my tendons are bigger? You could say yes, but it's hard to really be definitive. um How much does that relate to function? You'd think it would, but the next outcome was looking at tendon stiffness, which is, you know, some may associate that with poor outcomes being like, oh, why do I want to be stiff? But Tendon stiffness is a very strong uh proxy for the health of the tendon. We want tendons to be stiff. The stiffer they are, the more efficient they are transferring force, transmitting force from muscle to bone. And so we like stiffness when it comes to tendons. So four studies evaluated the effect of collagen supplementation on tendon stiffness. The Lee paper reported significantly greater percentage increases in tendon stiffness. So while that same paper, that same Lee paper didn't show cross-sectional area improvements, it did show a significant uh change in tendon stiffness in the collagen group. So I think it was whatever they used to measure stiffness, uh the value was plus 15.4, whereas in the placebo group, it was plus 4.6. The NALTI paper observed stiffness increases of plus 56 % in the collagen group and plus 18 % in the placebo group. Again, I don't know what that means in terms of what the units of measurement, but just looking at those values, they seem pretty good. The JEGA study, one of the JEGA studies found that patellar tendon stiffness increased by 20 % in the collagen group. and 21 % in the placebo group. Again, no significant difference. So this is a paper that didn't show any effect. What about physical performance? So there was a Liz et al paper and the NALTI paper also looked at collagen supplementation on performance. And they found that uh collagen plus vitamin C, the collagen plus vitamin C group showed a greater eccentric rate of force development. I think we can say rate of force would be um power, rate of force, uh acceleration you could say, and also eccentric deceleration impulse. So I think we're looking at sprinting, jumping, landing, those sorts of things, uh with also improvements in eccentric deceleration rate of force development. But they say that no between group differences were observed for counter movement jumps for height, a squat jump for performance or reactive strength index. No difference, no between group differences were observed for the counter movement jump height and power or broad jump distance. They also not just touched on tendon adaptation, but some studies also looked at muscle, muscle strength. and muscle volume and muscle cross-sectional area. I guess muscle volume and cross-sectional area is about the same thing. I'll just make a brief comment on these. So they said, among the four studies investigating the effects of collagen supplementation on muscle cross-sectional area or thickness, two of the papers demonstrated statistically significant benefits of collagen over placebo, while two papers did not. When it came to muscle strength, across all six included studies. Resistance training significantly improved muscle strength over time. However, no statistically significant group or timed interactions were observed in any trial. Collagen supplementation did not confer additional strength benefits beyond resistance training alone. So like I say, just a brief mention, they do go into detail, but I thought not really worth diving into that. We're focusing on tendons for this particular episode. Okay, let's talk about the discussion. Like I said, I might be repeating myself a little bit, but it's gonna be nice to tie a little bow in this because they do actually come up with some recommendations and protocols for you to implement. And yet just to have a nice slight different angle on things. In the discussion, they said, the purpose of this systematic review was to evaluate the effects of collagen supplementation on tendon related outcomes, including tendon cross-sectional area. tendon stiffness, physical performance, muscle cross-sectional area and thickness, and muscle strength. The current literature suggests strong evidence, so grade A level evidence, supporting increases in tendon cross-sectional area and tendon stiffness when collagen supplementation is paired with structured appropriately loaded resistance training. I'll talk about what appropriate appropriately loaded resistance training actually is. The current literature suggests conflicting evidence, i.e. grade C, for physical performance outcomes, with some studies showing improvements in eccentric force production and neuromuscular function during a stretch-shortening cycle, and others showing no effect, suggesting that these benefits may be task-specific. There is conflicting evidence, again, grade C, for changes in muscle, cross-sectional area and strong evidence, grade A, against an effect on muscle strength beyond what can be achieved with resistance training alone. Across the included studies, collagen supplementation combined with resistance training generally resulted in greater increases in tendon cross-sectional area compared to placebo. This is um quite promising. Like I say, the studies vary. The studies are few and far between. the sample sizes are small, but we're coming up with some pretty good data, some good outcomes, especially when it comes to the tendons getting bigger and getting more efficient at transmitting force. Three studies reported notable hypertrophy favoring the collagen supplemented groups with cross-sectional areas increasing ranging from approximately 6 % to 11%. These findings supported the hypothesis that collagen supplementation may enhance tendon remodeling when paired with sufficient mechanical stimulus. When paired with sufficient mechanical stimulus. I'll repeat myself there, cause that's very important. This adaptation is likely driven by the synergistic effects of repeated loading and increased collagen bioavailability, which together stimulate collagen synthesis. So we want the adaptation signal along with the building blocks. We need those two things. Ingesting collagen leads to a marked rise in circulating collagen specific amino acids such as glycine, proline, hydroxyproline and hydroxyglycine which peak approximately one hour post consumption. Accordingly, timing collagen intake 60 minutes before the training stimulus may be critical to ensuring that these amino acids are bioavailable, meaning ready to be used up, when mechanical loading occurs, thereby maximising their incorporation into tendon tissue. These findings indicate that while tendon hypertrophy can occur with training alone, collagen supplementation may further amplify this adaptation when compared under appropriate physiological and programmatic conditions. Four studies investigated the effects of collagen supplementation combined with resistance training on tendon stiffness. Significant increases in tendon stiffness favoring the collagen supplementation were reported by the Lee paper and the Nolte paper who administered a higher dosage of hydrolyzed collagen with vitamin C. They did 30 grams of this hydrolyzed collagen alongside structured resistance training protocols. So it seems like they found more effects on stiffness in the papers that had that upwards higher dosage. Across the included studies, the trials using higher collagen dosages between 15 to 30 grams per day tended to report greater increases in tendon stiffness compared with studies using lower dosages of around about five grams per day. These adaptations are thought to result primarily from increasing gene expression associated with anabolic responses to mechanical strain, which promotes collagen synthesis, turnover and enhanced cross-linking of collagen fibers. Tendon stiffness adaptations are highly dependent upon loading intensity. This is where we talk about what this resistance training usually is. And all these different studies had different protocols, but they said that this high intensity resistance training, which they said is 70 to 90 % of your one rep max. leads to greater overload of the muscle tendon unit and thus generates greater tendon strain, eliciting a stronger adaptation stimulus. Let's unpack that. So your one RM, if we're talking about say a deadlift or a squat, your one repetition max, one RM, is the amount of weight where you can lift it once and couldn't possibly do it twice. So it's this one maximum. effort that you can put for one repetition. If you take that weight and you do 70 to 90 % of that and that is your workout weight. So you might do you might take your one rep max or calculate it, try your best to estimate it and do 70 % of that. Still quite hard. You could probably get maybe six reps of that before it becomes before you feel like you have maybe one or two reps left in you, then you rest. So it's quite heavy stuff. That's the heavy stimulus, the high intensity resistance training stimulus that is believed to elicit a really strong adaptation stimulus to the tendon. If we are talking about, say, doing something for proximal hamstring tendinopathy, and we do, say, theraband curls, uh or you do bodyweight bridges, or you do bodyweight lunges, it doesn't seem like that is a strong enough adaptation stimulus to trigger the tendon to be like, I need to adapt, I need to get stronger. And obviously if you have a tendinopathy and you're, know, in significant pain, aggravation, irritation after lifting even 50 % of your one RM, okay, we do need to fall back on symptoms. But eventually you can see the importance of not just keeping to body weight exercises or low weight, high rep ranges and just expecting to optimize your tendon recovery. We do eventually need to poke into those higher resistances when the tendon is stable enough to do so. Then we compare it with the collagen and then we can enhance these effects as this paper suggests. Supplementation with higher doses of 15 to 30 grams of hydrolyzed collagen may further potentiate these remodeling processes by increasing the availability of collagen specific amino acid precursors necessary for collagen synthesis. So they do recommend sort of nudging into those higher ranges, 15 to 30 grams. The collagen powder that I have, one scoop is 30 grams, I believe. What I tend to do, I don't know how many, I think it's in the higher milligrams, uh but I just get one of those uh vitamin C drops tablets that just dissolve in water. And so I have a glass of water. I'll drop my vitamin C tablet in there. I think that's like a thousand milligrams. So, oh, I cut it in half. I take the 1000 milligram tablet, I cut it in half. I'll leave the other half in the container and drop half of it in. So that's 500 milligrams. So it's a high, high dosage of vitamin C. um Don't know if it's, what happens if I overkill the vitamin C, maybe I should just put it in quarters. But then 30 grams of that collagen, stir that all in together. um I'd say my early, early workouts when I wake up, I'm trying to squeeze in a workout before my daughter wakes up. It's definitely not. an hour, I definitely don't have that time, but um there's still going to be that training stimulus. And there's still going to be, you know, the highest bioavailability will be probably straight after my workout, because my workouts about 60 minutes. um Should I be timing it with doing say a deadlift? Maybe if I am symptomatic, or if I do have a reactive tendinopathy in the future, that's might be something that I do. um But Just letting you know that's how basic it needs to be when prepping this stuff. Or you could just do what Keith Barr does and buy some orange juice. ah I do know there's a fair amount of sugar in orange, most orange juices. So um I'd be careful with that. Okay, uh summing it up, like the paper does say, these structural adaptations are biomechanically meaningful as increased tendon stiffness and cross-sectional area are associated with improved force transmission. stretch shortening cycle efficiency and greater tendon load tolerance. This paper does have limitations though, and I think it's important that we share that. So several limitations must be acknowledged when interpreting these results. All these included studies utilized randomized controlled designs. The quality did vary with some lacking detail reporting on the allocation of concealment, blinding and the power calculations. sample sizes, i.e. like the size of the groups, were generally small, limiting generalizability and statistical power. There was also considerable differences in the collagen supplementation protocols, including differences in the collagen type, the dosage, the timing, whether vitamin C was included or not. And this variability complicates the identification of an optimal supplementation strategy. Additional limitations include inconsistent resistance training protocols across the studies that just varied in frequency, intensity, and whether they were supervised or not. Additionally, because all included studies combined the collagen supplementation with structured exercise interventions, it remains difficult to fully establish the independent contribution of the supplementation from the training induced adaptations. Outcome measures were not all standardized as the imaging techniques to look at the cross-sectional area. Imaging techniques and anatomical landmarks and performance tests would vary widely, reducing the comparability across trials. The participants were varied across the studies, which included both trained athletes and recreationally active or untrained individuals. You could imagine that a recreational or untrained individual could have more potential to say increase their cross-sectional area or their stiffness if they're starting from a lower base, whereas trained athletes may have been closer to their ceiling already and may have smaller benefits, but still meaningful. This may influence baseline tendon properties and the adaptation responses to collagen supplementation. uh Additionally, intervention durations were, some were short, some were between um three weeks, where some up to 15 weeks, which may not have been sufficient enough to capture long-term adaptations. These limitations underscore the need for future trials to employ standardized training and testing protocols, recruit more diverse populations, and incorporate longer follow-up periods to better elucidate a role. of collagen supplementation in musculoskeletal adaptation. So in conclusion, the findings of this systematic review provide a provisional, evidence-informed framework for collagen supplementation strategies in athletic and clinical settings. First, supplementation should be paired with structured, high-intensity resistance training of more than 70 % of your one rep max, as mechanical loading is the primary stimulus driving tendon and muscle adaptation. Available evidence suggests that a higher dosage of hydrolyzed collagen of 15 to 30 grams per day may be more effective than lower doses, particularly for enhanced tendon stiffness. Ingesting collagen approximately 60 minutes prior to training appears to be the most physiologically advantageous timing as this coincides with peak serum concentrations of collagen-specific amino acids, thereby enhancing their availability during the collagen synthesis window initiated by mechanical strain. Supplementation can be limited to training days only as the mechanical stimulus is necessary for collagen incorporation into the target tissues. Collagen should be co-ingested with vitamin C of more than 50 milligrams to facilitate extracellular cross-linking of collagen fibrils. So yes, making sure we're pairing with loading and this can like, it doesn't need to be taken. This collagen doesn't need to be taken daily. If you're not loading up your tendons daily, just take it on your training days because like we say, we need that pairing of the training stimulus with the collagen. We wanna sort of time that wave very closely. So again, while there are limitations to this paper and they didn't come up with a lot of robust papers, It did uh help summarize our current understanding and give us some nice practical guidelines for um finding these things. I would suggest when looking at a collagen supplementation, just do your research into high quality third party tested things because um you can if purchased online, if purchased via like Amazon or something like that um can be quite low quality or misleading ah products that are out there. So just make sure that you trust and have good reviews and look into doing your own diligent research into finding some good quality collagen supplementation. If you do decide to follow this particular protocol, because I do know the dangers and online purchasing, especially with supplements, is just covered with fraud and misuse in. all these other claims, just be very, very careful. And I hope this helps create a nice structured laid out plan. And I'm glad this paper exists. Like I say, it's sort of shifting my understanding and knowledge around the collagen supplementation. Now you're up to date. You're up to date with the latest what's out there. And if more gets released, I'll be the first to tell you about it. So I hope you enjoyed this episode and we'll catch you in the next one. If you are looking for more PhD resources, then check out my website link in the show notes. There you will find my free PhD 5 day course, other online content and ways you can personally connect with me. Well done for taking an active role in your rehab by listening to content like this and together we can start ticking off all of your rehab goals and finally overcome your PhD.