Does collagen help CrossFit athletes?
For the shoulders, elbows, wrists and Achilles that CrossFit loads at high volume, the trial evidence suggests collagen may help, provided you take it before the session and keep it up for months. It will not add kilos to your snatch, and it is not a substitute for whey, creatine or an intelligent programme. What makes CrossFit different from most gym training is the combination of heavy barbell work, gymnastics under fatigue and high-repetition plyometrics, often in the same hour. Muscle recovers from that in a couple of days; tendon and ligament do not, which is why the injuries that keep CrossFit athletes out of the box are overwhelmingly connective-tissue injuries. This page covers what the sport does to those tissues, the dose and timing the research used, what the trials found (with the null result included) and how a 20g ready-to-drink sachet and a collagen + creatine sachet fit a CrossFit week.
What CrossFit does to connective tissue
Start at the top. Kipping pull-ups, toes-to-bar, muscle-ups and butterfly pull-ups move the shoulder through its full range under load at speed, and the rotator cuff and long head of biceps take the strain at the bottom of every rep. Overhead squats, snatches and jerks demand the same joint stay stable at lockout. Elbows and wrists take the front-rack, the handstand walk and the false grip, so medial and lateral elbow tendinopathy and wrist pain are common complaints among people who have added volume quickly. Lower down, double-unders, box jumps and burpees are pure plyometric load through the Achilles and patellar tendon, and a workout with 100 or more of them is not unusual. Heavy squats, deadlifts and cleans load the patellar tendon, the hip and the lumbar spine.
Two features amplify this. First, CrossFit is done for time, so technique degrades under fatigue and tendons take load in positions they were not prepared for. Second, the sport rewards adding skills and volume fast, while tendon collagen turns over on a timescale of months and has a poor blood supply. The muscle keeps up; the tendon lags. Add the sheer volume of muscle damage from high-rep eccentric work (think 150 wall balls) and you have the two things collagen research has actually studied: tendon adaptation to loading, and soreness after damaging exercise.
The protocol: dose and timing for CrossFit
The research protocol is to take 15β20g of hydrolysed collagen with vitamin C 30β60 minutes before the session that loads the tissue, so that glycine, proline and hydroxyproline peak in the blood while the tendon is working, and to keep a smaller daily dose going for months. Creatine belongs in a CrossFit athlete's routine regardless: 3β5g a day supports the repeated high-power efforts that define the sport.
| When | How much | Why |
|---|
| 30β60 min before a metcon, skill session or heavy day | 15β20g hydrolysed collagen with vitamin C | Shaw 2017 pre-loading window; Lee 2023 shows a dose-response up to 30g |
| Rest and active-recovery days | 5β10g | Dose used in the 12- to 24-week tendon and joint trials |
| Creatine monohydrate | 3β5g daily | Kreider 2017 maintenance dose; Antonio 2021 on safety |
| Around a damaging session or competition | 20g daily for the days either side | Clifford 2019 soreness protocol (9 days) |
| Minimum commitment | 8β12 weeks | Tendon adapts slowly; the shortest positive trials ran 12 weeks |
Collagen is low in leucine and does not replace whey or food for muscle recovery. Treat it as a tendon-specific addition on top of a normal protein intake. For more detail see collagen dosage for athletes.
What the trials show
Pre-loading. Shaw 2017 gave 15g of gelatin plus vitamin C an hour before six minutes of jump-rope exercise and found blood markers of collagen synthesis roughly doubled against placebo; the engineered ligaments grown from those athletes' serum were stiffer and contained more collagen. Lee 2023 tested 0g, 15g and 30g and found the response scaled with dose. Double-unders are jump rope, so this is about as close to a CrossFit-specific trial as the literature gets.
Tendons. Jerger 2022 combined 5g of collagen peptides daily with 14 weeks of calf strength training and found a greater increase in Achilles tendon cross-sectional area than placebo. Praet 2019 gave 2.5g a day for six months to people with Achilles tendinopathy alongside eccentric rehab and reported better outcomes and return to running. Dressler 2018 found 5g a day for six months improved ankle stability in people with chronic ankle instability, which matters if you land box jumps badly.
Joints and soreness. Zdzieblik 2017 gave 5g daily for 12 weeks to young, active adults with activity-related knee pain and found greater pain reduction during activity than placebo; Clark 2008 found 10g a day for 24 weeks reduced joint pain in athletes. Clifford 2019 gave 20g of collagen peptides a day for nine days around a bout of drop jumps and found lower soreness at 48 hours, which is the closest thing to a trial on the day after a high-rep metcon.
Strength training. Kirmse 2019 (young men), Jendricke 2019 (women) and Zdzieblik 2015 (older men) each paired 15g of collagen peptides a day with 12 weeks of resistance training and reported greater gains in fat-free mass and strength than training alone. The effect sizes are modest and not everyone is convinced of the mechanism, but the dose is one a CrossFit athlete would take anyway.
Creatine. Kreider 2017 is the ISSN position stand: 3β5g a day maintains stores, and the safety record across decades of trials is strong. Antonio 2021 works through the myths (kidneys, water retention, cramping, hair loss) and finds no good evidence for them. Avgerinos 2018 reviews evidence that creatine may support cognitive performance under stress and sleep deprivation.
The honest null result. Aussieker 2023 gave 30g of collagen protein immediately after resistance exercise and measured connective-tissue protein synthesis in muscle over the following hours: no increase compared with placebo. That trial is a caution against two things: taking collagen after the session and expecting an acute effect, and treating collagen as a muscle-building protein. The stronger evidence is for months of daily use combined with loading, and the acute evidence is limited to blood markers.
How KUDU fits a CrossFit week
The trouble with the pre-loading protocol is the logistics: a 20g scoop in a shaker an hour before a 6 a.m. class. KUDU's 20g Liquid Collagen Protein is a 63ml ready-to-drink sachet: 20,000mg of hydrolysed bovine collagen (type I and III), 85 kcal, 0g sugar, 0g fat, dairy free and gluten free. It lives in the gym bag and you drink it in the car park. Four flavours (Sour Cherry, Peach, Orange, Strawberry & Vanilla), made in the UK, and Informed Sport certified, which matters for anyone competing in sanctioned events with drug testing.
For strength days the Collagen + Creatine sachet pairs 10g hydrolysed collagen with 5g creatine monohydrate and vitamin C in a 44 kcal mix-with-water sachet (Mixed Berry or Tropical). A box of 14 liquid sachets is Β£34.95, from Β£1.99 a sachet on subscription; the Β£12 Sampler Box lets you try all four flavours. 60-day money-back guarantee, 4.8 stars from 480+ verified reviews.
A CrossFit weekly collagen plan
| Day type | Collagen | Creatine | Timing |
|---|
| Heavy barbell day | C+C sachet (10g) or 20g sachet | 5g (in C+C) | 30β60 min before |
| Gymnastics or skill session (pull-ups, muscle-ups, HS walk) | 20g sachet | 3β5g any time | 30β60 min before |
| High-rep metcon (double-unders, box jumps, wall balls) | 20g sachet before, 20g the next day | 3β5g | Pre-load, then soreness protocol |
| Rest or active recovery | 10g (half a sachet) | 3β5g | Any time |
| Competition week | 20g daily; 20g before each event day | 3β5g daily | Mornings; nothing new on the day |
| Deload week | 10g daily | 3β5g | Keep the habit going |
CrossFit guides
Collagen for CrossFit: FAQs
Should I take collagen before or after a WOD?
Before. The pre-loading trials dosed 30β60 minutes before exercise, and Aussieker 2023 found that 30g after resistance exercise did not raise connective-tissue protein synthesis. Have the sachet before the warm-up and your whey afterwards.
Does collagen help with elbow tendinopathy from pull-ups?
There is no trial on elbows specifically. The tendon trials (Praet 2019, Jerger 2022) were on the Achilles and paired collagen with a loading programme, so the honest transfer is: collagen may support the tendon while you rehab it with appropriate loading and a temporary reduction in kipping volume. It is not a treatment on its own.
Can I take collagen and creatine together?
Yes. They work through different routes (amino acids for connective tissue; phosphocreatine for repeated power output) and there is no interaction. The C+C sachet combines 10g collagen with 5g creatine and vitamin C for exactly this reason.
Is collagen useful for shoulder stability in gymnastics movements?
Indirectly. Ligament and rotator cuff tendon are type I collagen, and Shaw 2017 showed pre-loaded gelatin increased collagen content in engineered ligaments. That is a mechanism, not a clinical trial on shoulders. Shoulder stability comes from strength and control work; collagen supports the tissue that work builds.
How long until I feel a difference?
The soreness trial ran nine days; the knee-pain trial ran 12 weeks; the tendon trials ran 14 weeks to six months. Give it a full training cycle before judging, and be sceptical of anyone promising results in a fortnight.
Other sports: runners, Hyrox, cyclists, rugby and football, the gym. Browse the full liquid collagen range and the Collagen + Creatine collection.
