Should Climbers Take Collagen Supplements? (Make an Informed Decision) | Research Review
Hooper’s Beta Ep. 100
INTRO
As a physical therapist, I spend most of my time helping people heal from injuries. To do this, I prefer to take a research-based approach, because I believe the scientific method is usually our best bet for arriving at useful conclusions.
As a climber/YouTuber, I like to take the same approach to making these videos, so when we decided we wanted to join the rather polarizing discussion on collagen supplementation for climbers, my first thought was simple: “show me the research.”
Who cares if my buddy swears by collagen supplements? Who cares if that influencer says it cured his tendinitis? Who cares if pro athletes are sponsored by collagen companies? Just show me the science and the decision will be obvious!
Ugh, well, as usual, it’s not quite that easy. In fact, this was one of the toughest videos we’ve ever made. Let’s do a brief run-down of what collagen actually is so we have some context, and then we’ll get into the real nitty gritty stuff.
Emile: Bro, hold on. What if, instead of doing it the hard way with all the research and analysis and blah blah blah…what if we just did it the easy way, the way the influencers do it??
see video for skit
Jason: Yeah, I don’t know, I mean on one hand I like sick beats, but on the other hand: science, honesty, accurate information, integrity, not misleading people with false promises...
Just to be clear: this video is not sponsored in any way by collagen companies and I have no conflicts of interest to declare.
ALSO! Just a note: I recommend watching/reading to the very end of this video, because we left a nice little thought bomb for you all.
WHAT IS COLLAGEN?
Collagen is a protein that helps make up the structure of bones, skin, muscles, and most important for us climbers, connective tissues. In fact, collagen typically makes up over 70% of the dry weight of ligaments and tendons!
Like other proteins, collagen is made up of amino acids. The exact amino combination depends on the type of collagen (of which there are 28 different kinds), but all collagen is made up of high amounts of proline, glycine, and hydroxyproline. For climbers, the most important types of collagen are Type I, II, III, V, and XI, as those are the kinds in tendons and ligaments.
A tendon is formed in layers. The tendon itself is the largest unit, which is made up of fascicles, which is made up of fibers, which is made up of fibrils. A fibril is made up of collagen fibrils which are made from collagen molecules. This is an important distinction BECAUSE, collagen type I, II, & III are all distinguished by the fact that they are fibril forming, AND, those are the 3 types of collagen we will focus on in this video!
Quick side note: those are not the only fibril forming ones, but are the most abundant ones also found in tendons and ligaments. The entire family of fibril forming collagens that are found in tendons and ligaments are: Type I, II, III, V, and XI.
Type I collagen makes up 90% of the connective tissue found in tendons and ligaments. Type II and III can also be found in tendons and ligaments, with III having a larger quantity than II. This heterogeneity can be important in the molecular makeup of tendons and ligaments and can improve the health of the connective tissue. In fact, it was found that although Type V and XI make up a small percent of the connective tissue in a tendon/ligament, their disruption can alter the structure, number, and organization of the fibrils which ultimately affects the health of the tendon/ligament! Additionally, Collagen VI is involved in the development of tissue-specific extracellular matrices, repair processes, and in the maintenance of tissue homeostasis (Mienaltowski MJ, Birk DE). Finally, it is also important to also note that Amino Acids plays a role here! Having the proper amino acids available, such as Leucine, is required to help regulate linear fibril growth (keep it well organized) and may even boost collagen production!
The takeaway here is that it is important to recognize that even though those nutritional supplements may focus on Type I and III, they are not as effective without the full complement of necessary collagens and even amino acids! It’s a team effort, after all! Just like this channel: you may see my face on this screen more often, but without Emile putting in countless hours editing and helping to organize these show notes, as well as directing the filming and producing such excellent videos, these videos simply wouldn’t exist!
HOW DO OUR BODIES USE COLLAGEN?
Collagen is produced naturally in our bodies by breaking down the proteins we eat into amino acids and then using those to create collagen.
It’s actually kind of a round-about process; if you were to eat a big chunk of collagen, like a cow hoof, your body can’t just transfer that collagen directly into your tendons. First it would have to break down the hoof into amino acids and then it would use them for various purposes, including collagen production.
Also, amino acids aren’t the only things needed for collagen production. Research has shown nutrients like vitamin C, zinc, and copper need to be present in sufficient amounts in order for collagen production to even happen. Your body also needs energy to do…well, anything! So you have to be eating enough calories to allow it to repair and build with collagen.
So if our bodies produce their own collagen from the food we eat, why would we need to take a collagen supplement? Let’s find out.
THE THEORY BEHIND TAKING COLLAGEN SUPPLEMENTS
The idea behind collagen supplementation is simple: the more the better! Give me an easily digestible source of collagen building blocks so I’ll never be lacking!
Us climbers are constantly pushing our connective tissue to the limit, some of us don’t eat very healthy diets or may not be consuming the right proteins, and there’s always the looming issue of under-eating in this sport. So why not take a collagen supplement to make sure we have what we need? Heck, even if we’re not lacking any of the collagen building blocks, maybe some extra would help our bodies fortify those tendons faster!
And let’s take the supplement a step further: on top of the amino acids, we’ll add in those other nutrients like vitamin C so there’s even more reason for our bodies to be collagen-producing powerhouses.
More collagen intake = more building blocks available = more collagen production = faster recovery and stronger fingers, right? The logic is simple, so let’s see if there’s some research out there to verify it.
NEW MERCH FOR EPISODE 100!
By the way, in celebration of 100 episodes of Hooper’s Beta, we’ve got new t-shirts! There are some sweet new designs AND they’re all available in hoodies, long-sleeves, tank tops, etc. Link in description!
THE RESEARCH
Scientific research generally needs to meet specific criteria to be considered valid and conclusive (by anyone other than salesmen, that is). Among other things, studies should have large, representative sample sizes, control groups, randomized assignment, objective measurements, and a double-blind approach to maximize statistical relevance.
To do all that is a tall order. Here are my summaries and opinions on the five most climbing-relevant research I could find. For citations and more in-depth analysis, check out the full show notes on our website (link in description).
Article I: Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis
The first article is: Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis.
Overview: In this randomized, double-blinded 2017 study, researchers gave 5 or 15 grams of gelatin or a calorie-equivalent placebo to a group of 8 participants one hour prior to exercise. The gelatin and placebos were delivered in a beverage containing vitamin C, and they used blood markers to measure collagen synthesis.
Result: Increases in blood markers in all groups after exercise, with the greatest increase in the 15 gram group. (53.9% increase in placebo group, 59.2% in 5g, and 153% in 15g group.)
Researchers’ Conclusion: Consuming gelatin and a vitamin C supplement increases the appearance of collagen-related amino acid components collected in blood serum. Subjects who consumed high amounts of gelatin one hour before exercise showed twice as much collagen synthesis as the placebo or low gelatin group.
My Take: These results show that consuming gelatin and vitamin C prior to exercising can potentially improve your training results and collagen synthesis, and that consuming 15 grams of gelatin may be better than 5. However, I have two issues with this study.
First, the placebo they used was a simple carbohydrate, meaning they were comparing the collagen synthesis of people consuming collagen vs. people eating a bit of sugar. I think there’s already lots of evidence out there that eating protein is more beneficial for recovery than sugar, so to me this study doesn’t provide as much new information on collagen as it could. In my opinion a more useful comparison would have involved a common dietary protein source as the placebo, like eggs or meat.
My second issue, and this is a big one, is that the number of participants was miniscule. There were eight in total, and since they were split into three groups, there were only a few participants per group. By scientific standards that is extremely weak, to the point where I personally don’t find this study to be at all conclusive.
The next article is: Breaking down, starting up: can a vitamin C-enriched gelatin supplement before exercise increase collagen synthesis?
Overview: Is this a glitch in the matrix or does that sound eerily familiar? Turns out, a different researcher analyzed the data from the last article and published their own conclusions.
Result: N/A (data provided by Article I)
Researchers’ Conclusion: The previous study does not provide definitive answers to improving tendon and ligament strength after exercise. More conclusive answers will come from studies in which participants are given different foods/supplements in a blinded fashion and with better objective measurements.
My Take: I find it annoying yet unsurprising that collagen companies and influencers continually cite the first article as “proof” that their product works while never mentioning this article, which comes to a very different conclusion using the exact same data.
The next article is: The effects of collagen peptides on muscle damage, inflammation and bone turnover following exercise: a randomized, controlled trial.
Overview: In this randomized, double-blinded 2019 study, researchers split 24 male participants into a treatment group which received 10 grams of collagen peptides before and after exercise and a control group which received a sugar placebo. The exercise performed was a series of jumps. They measured changes in sequential jump height, muscle soreness post-exercise using the Visual Analogue Scale (VAS), and also looked at serum protein release and bone turnover markers post-exercise.
Result: The collagen peptides had little to no influence on serum protein release and bone turnover markers, with possibly some small increases in leukocyte numbers with collagen peptide supplementation post-exercise. The VAS showed a 4-54mm decrease in muscle soreness 24 to 48 hours after exercise, and while the jump height was reduced in both groups after exercise, recovery was faster in the collagen peptide group.
Researchers’ Conclusion: Collagen peptide supplementation improved recovery speed as indicated by jump height performance and reduced muscle soreness following exercise based on the VAS, but had little to no effect on serum protein release and bone turnover markers post exercise.
My Take: The larger sample size of this study is definitely an improvement to me over the previous articles (though still quite small).
It’s nice that they used both subjective and objective measurements to determine their results. Unfortunately, the subjective measurement they used, the VAS, is a flawed research tool in my opinion. Using this system, participants simply draw a line somewhere on a 100mm scale to denote how sore their muscles were, from “not at all” to “extremely.”
Without obvious reference points on the scale, it’s tough for people to have any kind of consistency day-to-day. Like, you could have the same pain level over the course of two days, but the first day you might draw the line at 19mm and the next day you could draw it at 25mm, thinking you’re drawing the line in the same spot.
On the other hand, there can also be issues with subjective questionnaires that use a 0-10 scale, because it does not allow the individual to select more accurate numbers such as 2.5 rather than 3. Issues like this in subjective exams that have not been validated gives me pause, so I personally don’t give much weight to these results.
That leaves me with the objective measurements. The serum protein release and bone turnover markers didn’t show much or any evidence in favor of the collagen, but the jump height testing did! This is exciting, however, it brings up the same issue I had with the first article: the placebo was sugar.
So for me this study really only shows one thing: for exercise recovery, consuming collagen is probably better than eating sugar.
Our next article is: Oral Supplementation of Specific Collagen Peptides Combined with Calf-Strengthening Exercises Enhances Function and Reduces Pain in Achilles Tendinopathy Patients.
Overview: In this 6-month, double-blinded, placebo-controlled study done in 2019, 20 physically active participants with Achilles tendinopathy were split into two groups. One group was given collagen prior to exercising and the other was given a placebo. Halfway through the study, they switched; the first group was switched to the placebo and the second group was given collagen. They used the Victorian Institute of Sports Assessment-Achilles, or VISA-A, to measure results, as well as microvascularity measurements via ultrasound.
Result: Improvement in tendinopathy based on VISA-A subjective questionnaire for collagen groups compared to placebo. Decrease in microvascularity for both groups receiving collagen, indicating no difference in effect between the two interventions and no evidence for a benefit of CP supplementation on tendon vascularisation for the objective portion.
Researchers’ Conclusion: Despite the study not having large statistical power due to the small sample size, supplementation of collagen peptides may accelerate the benefits of exercise, in this case, eccentric strengthening. However, no firm conclusions can be drawn regarding collagen supplements in treating chronic Achilles tendinopathies, and using ultrasound is unlikely to be useful in determining the potential in vivo mechanism of collagen supplementation as a treatment with exercise.
My Take: I like that this was a longer study and that the treatment groups were switched at the midway point. The researchers’ conclusion also seems reasonable to me; they even mention the limited statistical power of such a small sample size.
Moreover, while the VISA-A is a subjective measurement, it is supported by research as a valid and reliable questionnaire, so that’s a potential win for collagen in this study. On the other hand, the objective measurements were inconclusive.
This is another possible step in the right direction with fairly promising results, but it still has some shortcomings that once again make it less than conclusive in my eyes.
Article V: Minimizing injury and maximizing return to play: Lessons from engineered ligaments
The final article is: Minimizing injury and maximizing return to play: Lessons from engineered ligaments.
Overview: This article was written in 2017 by Keith Baar, who was also one of the researchers in the first article we analyzed. In this article, he examines research that was performed on engineered tendon-like sinew in relation to loading and sinew function, the effects of hormones on sinew function, and most importantly for this video, nutritional interventions on tissue function. More specifically, it discusses if collagen supplements combined with vitamin C could increase collagen production in vitro.
Result: N/A (used data from other articles)
Researchers’ Conclusion: Amino acids enriched in collagen (proline, hydroxyproline, and hydroxylysine) added with vitamin C can improve collagen synthesis in engineered sinew. Blood flow to tendons is limited when inactive, suggesting collagen needs to be present prior to exercise to be delivered to tendons/ligaments. Recommendation: consume 15 grams of gelatin 30-60 minutes before exercise.
My Take: This now famous (or infamous, depending on who you ask) study was the central pillar of Emil Abrahamsson’s viral video “Hangboard Training 2 Times Per Day for 30 Days,” and is frequently cited by collagen companies as evidence their product works.
On one hand, I think it’s great that the study was able to avoid a lot of the pitfalls of the other articles, like limited participants and subjective measurements, by doing the study in vitro. The results are clearly in favor of collagen supplementation for this engineered sinew. They even give recommendations at the end for how much and when to consume it!
On the other hand, there may be some serious issues with trying to generalize these in vitro results to human beings. If you don’t believe me, here are some of the differences the researchers themselves list between their engineered sinew and real human sinew.
These engineered tissues have more cells and less matrix
Their rate of collagen synthesis is significantly higher
They expres more developmental collagen isoforms
They are much weaker than adult sinews]
I’m definitely not saying the results are useless, just that we can’t yet say with high confidence that they are applicable to humans. In my opinion, this article is at best another “maybe,” but there are far too many variables to say for sure.
OTHER RESEARCH (SHOW NOTES ONLY)
Enough of all this limited research, is there any TRUE article out there about collagen even if it isn’t related to climbing?! Let’s do a speed round and see what we found!
Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis
They selected 19 studies for a total of 1,125 participants (yahoo!) between ages of 20-70.
Their meta-analysis showed favorable results of collagen supplementation compared with placebo.
Usually I love meta analyses, but in this case I think you really need to break down each article. Were the results favorable because of the collagen or just because they now had a healthy diet which improved their skin among other factors? Regardless, that’s a +Plus for collagen
This looks great! Meta analysis of randomized controlled trials. Oh wait, randomized placebo-controlled trials. What was the placebo? This brings up the same argument as before. Are the results going to be positive because one group had all the building blocks and the other didn’t?
They found that collagen is effective in reducing OA symptoms as indicated by changes in WOMAC and VAS scores.
The VAS is the visual analogue scale which is a subjective pain scale. Which we already broke down earlier.
The WOMAC is another self administered questionnaire given to people with hip and knee OA…
Another determination made by a subjective scale. Let me remind you, we cannot say that is NOT significant, it is certainly helpful! It’s just not as ideal as having objective data to also support it.
OK so this is interesting! They have 53 participants now and a much tighter demographic as they were a much closer age range and all had sarcopenia.
It was randomized and double blinded, great!
They all went through a 12-week guided resistance training program and this is also interesting, the collagen peptides were given AFTER exercise. It was also 15grams, cool!
BUT, the other group was just given a silica replacement as a placebo. They described the silica as a safe good additive that induces no metabolic effects…
So once again it shows that yes! If you give someone nothing after exercise vs collagen which has amino acids, they will do better! That makes sense, but it doesn’t prove that collagen is better than say… a serving of black beans or a chunk of chicken.
Another one starting off strong with 57 participants. Unfortunately, once again just active young men. It would be nice if some of these studies would include women too, but alas they did not.
They gave 15 grams of collagen peptide to one group and placebo to the other.
The placebo was once again silicon dioxide which “does not provide energy”.
Interestingly, they also provided the collagen vs placebo after exercise, but also limited participants to ONLY their collagen or placebo for the first hour post exercise.
Which is… good? At least from a science point of view. They essentially wanted to see if taking collagen vs taking absolutely nothing for 1 hour post exercise would have an effect.
Their results? Both groups showed increases in all strength tests, and “a trend for slightly more pronounced effect in the [collagen group]”
OVERALL TAKEAWAY FROM THE RESEARCH
First I want to mention that there are of course many other articles out there on collagen, but they focus on things like skin aging and arthritis. I think those are a bit outside the scope of this video, but if you’d like to see my summaries and opinions on some of them, I’ve written them up in the show notes on our website.
Overall, I think it’s promising that most of the research we examined found some possibility of benefit from collagen supplementation. However, there are simply too many issues with each study for me to consider them conclusive.
First, the sample sizes are way too small to be statistically powerful.
Second, the subjective measurements are either flawed or do not show the same results as the objective measurements. That isn’t necessarily the fault of the researchers, as objective measurements are difficult in these studies, but it still gives me pause.
Third, the total amount of research we have to look at for this topic is very limited as the field is still in its infancy.
Fourth, collagen research is often funded or partially funded by companies that would benefit from favorable results. That doesn’t mean the research is invalid, but it does raise concerns.
And fifth, even if none of those issues existed and I thought the research was simply incredible, simply delightful, it would not change the fact that the placebo they use for the control groups is usually sugar. That means the only thing the research could tell us for sure is that taking collagen supplements before or after exercise is better than eating sugar.
Now, I don’t know about you, but I’m not in the habit of eating sugar to recover from climbing. I eat food. I eat vegetables, eggs, fruits… Heck, I eat things that contain the building blocks my body needs to repair itself, and none of the current research even attempts to tell me if collagen supplements would be more beneficial than what I already eat.
So where does that leave us? In my opinion, at best, all the research can tell us right now is “maybe collagen supplements can help with exercise recovery compared to sugar (or nothing at all).”
To me, that’s not a compelling or even interesting conclusion. BUT, that doesn’t mean I’m against climbers taking collagen. Before I explain, I’m curious what you all think. Do you find the research convincing or do you think there’s more work to be done? Are there other research articles you think I should have included? Join the discussion down in the comments and if you like this video, consider hitting that thumbs up!
SHOULD CLIMBERS TAKE COLLAGEN OR NOT?
Here are some reasons you might not want to take collagen supplements:
One, they’re usually made from animal parts, so definitely not vegan if you’re concerned about that.
Two, they’re not regulated by the FDA, so it can be hard to know what you’re actually getting. The quality could vary wildly and you could be consuming unhealthy substances. There are some certifications available, but that’s still not the same as FDA regulation.
Sometimes it’s not even banned substances that are the issue. As pointed out by this article, A Dietician’s Guide to Collagen for Climbers, “Gnarly Collagen Pro, which is also heavily marketed toward climbers, has vitamin C and zinc added to it. Worth noting is that long-term zinc supplementation may cause anemia and copper deficiency. It can also interact with some medications, including antibiotics and diuretics.” That doesn’t mean supplements with zinc WILL harm you, it’s just something to look into if it concerns you.
Three, they can be expensive. The marketing on these supplements is intense and prices are all over the place. Are you willing to spend that much money on an unproven, unregulated product?
And four, no matter what, they’re not a magic bullet. We so often want to believe that if we just find the right pill or food or supplement that all our problems will go away and we’ll climb harder than ever! But… Do you have an inconsistent sleep schedule? Do you have a poor diet? Do you train without goals or focus? Do you overtrain? Do you neglect your injuries? Do you have bad technique? Are you dissatisfied or unhappy with your day-to-day life? Because a collagen supplement won’t fix ANY of those things.
Overall, I’m not actually for or against people taking collagen supplements; I’m for people making informed decisions. I think taking care of your sleep schedule is just as important as getting in an amazing climbing session. I think understanding your own strengths and limitations is better than listening to an influencer telling you to buy something.
For me it all comes down to cost-benefit relationships.
If you’re a pro athlete getting 9.5 hours of sleep every night with a massage therapist on hand and dietician making your food, collagen supplements probably won’t cost you much but also might not really help.
If you’re an average climber trying to juggle sleep with work and friends and diet and, oh, climbing, then maybe you think a collagen supplement would be helpful. In that case, the placebo effect alone could be worth it on top of the potential increase in collagen synthesis!
Or maybe you’ve got all those things totally dialed, but can’t get a solid snack in before your climbing session and you don’t mind paying for collagen with all the certifications…
No matter what, I recommend measuring the cost to benefit ratio to make an informed decision, and then tracking your results to see if it turned out the way you thought!
But enough of my opinions, let’s hear what registered dietician Danielle Roberts has to say on the subject.
EXPERT OPINION FROM A REGISTERED DIETICIAN
(see the video for the full interview!)
RECOMMENDATIONS IF YOU DECIDE TO TAKE COLLAGEN
If you do decide to try some collagen supplements, here are a few recommendations.
One, based on the little research we have to go on, it’s best to consume about 10-20 grams of collagen 30-60 minutes prior to climbing or training.
Two, make sure you’re getting enough vitamin C in your diet or get a collagen supplement with vitamin C added. Some will be quick to point out that heat destroys vitamin C, which they then use to infer that you should never put vitamin C into a hot drink. I don’t know enough about vitamin C to comment on that, but it seems like an easy enough issue to avoid..
Three, for a cheap alternative to expensive supplements you can use plain old gelatin and vitamin C gummies. As Nutrition for Climbers points out once again, “Two unflavored gelatin packets cost about $0.85.”
Four, don’t rely on supplements for all your nutrients! Eat good food!!
CONCLUSION
In conclusion, the problem with collagen supplements for climbers is not that they don’t work -- it’s that, from a scientific perspective, we don’t know if they work…yet! The research is still in its infancy, so despite what the marketing will tell you, no one really knows with a high degree of certainty how effective they are. But that will hopefully change soon if more quality research is performed.
Right now all I can say is: You have the power to decide if collagen supplements are worth trying. Don’t let influencers take that away from you!
Thank you all so much for joining us on our 100th episode, and if you’d like us to make another 100 episodes, hit that like button, subscribe!
Emile: And don’t forget to check out the new merch!!
Jason: Until next time…
Cut back to Emile and Jason still standing in the same spot.
Emie: Wait… Even if all the research WAS perfect and it was completely obvious that collagen supplements increase collagen synthesis compared to eating sugar…
Jason: …that still doesn’t give us much information for climbers in the real world…
Emile: …because climbing mostly relies on strong tendons and ligaments, and those take years and years to strengthen no matter what you do…
Jason: …and who’s to say how much collagen would affect that when combined with hundreds or thousands of variables…
Emile: …like training routines, diet, genetics, and even day-to-day habits…
Jason: …all of which would be compounded over massive time intervals…
Emile: …which means…
Jaon: …even if the research had been conclusive…
Emile: …would we have any idea if collagen supplements actually help you climb better?
They both turn to each other, wide-eyed, like they just had the biggest realization. Then they slowly turn to face the camera.l
Cut to black.
Disclaimer:
As always, exercises are to be performed assuming your own risk and should not be done if you feel you are at risk for injury. See a medical professional if you have concerns before starting new exercises.
Written and Produced by Jason Hooper (PT, DPT, OCS, SCS, CAFS) and Emile Modesitt
IG: @hoopersbetaofficial
RESEARCH
Structure, physiology, and biochemistry of collagens
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