Collagen Peptides for Tendon Recovery: A Skater's Practical Protocol

I wrote a broader piece on this site about joint supplements generally — glucosamine, omega-3s, turmeric, the whole shelf. Collagen got a paragraph in that one, which undersold it. For tendons and ligaments specifically — the tissues most likely to be nagging at you after a hard landing or an ankle roll — collagen is the supplement with the most specific, mechanistically sensible evidence behind it, and it deserves its own protocol rather than a passing mention.

This is that protocol: what the research actually supports, how to time it, and what it’s realistic to expect.

Why tendons and ligaments are a different problem

Muscle repairs itself relatively quickly because it has a rich blood supply. Tendons and ligaments don’t — they’re built from densely packed collagen fibers with comparatively poor circulation, which is exactly why a rolled ankle or a cranky Achilles tends to linger for weeks or months rather than days. Skating loads these tissues in a specific way: repetitive impact through the ankles and knees, and sudden sideways or twisting loads through the wrists on falls. That’s a lot of collagen-dependent tissue getting asked to do a lot of work, with a relatively slow repair mechanism supporting it.

That mismatch is the actual case for paying attention to collagen specifically, rather than joint supplements generally.

What the research supports

Hydrolyzed collagen peptides — collagen broken down into a more easily absorbed form — push collagen’s signature amino acids to peak levels in your bloodstream roughly an hour after you take them (between one and two hours for a standard hydrolysate; faster for the newer low-molecular-weight products). That timing matters, because the research points to combining that window with mechanical loading. The study everyone cites is Shaw, Baar and colleagues’ 2017 trial in the American Journal of Clinical Nutrition: 15 g of vitamin C-enriched gelatin taken one hour before six minutes of skipping roughly doubled a blood marker of new collagen synthesis compared with placebo, and 5 g did not. That is a marker in healthy young men, not a healed tendon — but it is the reason the advice is to take collagen shortly before the activity that loads the tissue, rather than at a random time of day disconnected from your session.

Vitamin C’s role is more specific than “general immune support.” It’s a required cofactor for the enzymes that stabilize newly formed collagen and hold its structure together — without adequate vitamin C, the body’s collagen-building machinery doesn’t function properly, which is part of why collagen and vitamin C are usually studied together rather than collagen alone.

The clinical evidence in injured tissue is smaller than the supplement industry implies, but it points the same way. Praet and colleagues’ 2019 crossover trial in Nutrients gave a small group of people with chronic mid-portion Achilles tendinopathy 5 g a day of a specific collagen peptide (split into two doses) alongside a twice-daily calf-strengthening programme, and the three months on collagen produced a larger improvement in pain and function (the VISA-A score) than the three months on placebo. Dressler and colleagues’ 2018 study in the Journal of Sports Science and Medicine gave 50 athletes with chronic ankle instability 5 g a day for six months and reported better self-rated ankle stability than placebo. Closest to this site’s readers, Nulty and colleagues’ 2025 trial in the European Journal of Sport Science found that middle-aged men taking 30 g of hydrolysed collagen a day alongside 12 weeks of resistance training got larger patellar tendon adaptations than training alone — although their strength gains were no bigger. A larger trial of collagen plus vitamin C in athletes with patellar tendinopathy (the Dutch JUMPFOOD study) had not published results when this was written, so “it works for jumper’s knee” is still a hypothesis. In every one of these, the supplement was tested as an addition to loading exercise, never as a standalone fix — and the exercise is doing real work in each trial where collagen showed a benefit.

It’s worth being precise about what’s actually been tested, because the individual pieces below come from different kinds of studies. The one-hour pre-exercise timing comes from acute research measuring a blood marker after a single dose, not from the tendinopathy trials themselves. Those clinical trials tested daily collagen alongside a rehab exercise program over three to six months, generally without pinning the dose to that exact pre-exercise window, and used different products and amounts — anywhere from 5 g to 30 g a day — rather than one standardized dose.

A realistic protocol

Nobody has run a single trial testing this exact combination as a unit. What follows is a reasonable synthesis of the two bodies of evidence above — the timing from the pharmacokinetic research, the daily consistency and pairing-with-loading-exercise from the clinical trials — not a protocol that was itself directly tested:

• 10–15 grams of hydrolyzed collagen peptides (a scoopable powder, usually flavorless, dissolves in water or coffee) — this sits in the middle of the range the trials used, and 15 g is the dose that moved the collagen-synthesis marker in the timing study
• Alongside 50mg or more of vitamin C — the timing study used about 48 mg; a small glass of orange juice covers this, or a low-dose supplement if you’re not near citrus
• Taken about an hour before your skate session or rehab exercises — this timing is drawn from research on when blood collagen peaks, not from the clinical tendinopathy trials directly
• Daily, consistently, for at least 12 weeks before judging whether it’s helping — this part does match how the clinical trials were run, which lasted three to six months

That last point is the one people skip. Taking collagen occasionally, or only on days your ankle feels bad, isn’t close to how any of this was studied, and it’s unlikely to produce the same result.

Who this is actually for

This makes the most sense for adults managing a slow-recovering strain or sprain, ongoing tendinopathy (a nagging Achilles or patellar tendon that flares with activity), or general connective-tissue resilience given how much repetitive load skating puts through ankles, knees, and wrists. It is not a treatment for an acute injury — a fresh, significantly swollen sprain or anything with sharp, severe pain needs an actual diagnosis before you’re thinking about supplements at all. See a doctor or physiotherapist first; add collagen to a recovery plan, not in place of one. If the injury in question is an ankle, this site’s ankle sprain guide covers what that plan should actually look like.

What it won’t do

Collagen doesn’t reverse existing tendon damage overnight, and it isn’t a substitute for the loading exercises that are the actual proven treatment for tendinopathy — it’s a supporting addition to them. If you’re not also doing the structured strengthening work a physiotherapist would recommend for a tendon issue, the supplement alone is unlikely to move the needle much. Set your expectations at “one useful piece of a recovery plan,” not “the fix.”

Safety notes

Hydrolyzed collagen is generally well tolerated, but check the source if you have food allergies or dietary restrictions — most commercial collagen is derived from bovine or marine (fish) sources, and occasionally porcine. Vitamin C at the doses used here is low risk for most adults, though very high doses from supplements generally (well beyond what’s in this protocol) can cause digestive upset in some people. As with any new supplement, if you’re managing a chronic condition or taking regular medication, it’s worth a quick check with your doctor or pharmacist before starting — not because collagen has significant known interactions, but because that’s a five-minute conversation worth having before you start rather than after.

Give it the full twelve weeks, pair it with actual loading exercise, and treat it as what it is: a reasonably well-supported, low-risk addition to a recovery plan — not a replacement for one.