the gelatin and vitamin c trick athletes use on tendons

I found this study while looking for something else entirely, and it is the one that moved collagen from the beauty aisle to the sports shelf in my head.

the study

Shaw, Lee-Barthel, Ross, Wang and Baar, American Journal of Clinical Nutrition, 2017. Eight healthy men, three arms, placebo or 5 grams or 15 grams of vitamin C enriched gelatin, taken one hour before six minutes of jump rope, three times a day for three days.

They measured a marker of collagen synthesis in blood. The 15 gram group roughly doubled it compared with placebo. They also ran the participants' blood over an engineered ligament in the lab and saw improved mechanical properties.

Eight people is small and it was men only. But the design is unusually smart, and it has shaped how sports scientists think about connective tissue ever since.

why the hour matters

Tendons and ligaments have a poor blood supply. That is why they heal slowly and why an ankle sprain outlasts a bruise by weeks.

Poor blood supply means the delivery window is narrow. You want circulating amino acids at their peak at the exact moment mechanical load is telling those tissues to rebuild.

Loading is the signal. Amino acids are the supply. The hour lines them up. Take the same amount at a random time and you have supply without signal.

and why vitamin c is in the study name

Because without it the rest does not happen. Two enzymes, prolyl hydroxylase and lysyl hydroxylase, need vitamin C as a cofactor to modify collagen strands so they can wind into a stable triple helix. No vitamin C, no stable collagen, regardless of how many amino acids are circulating.

They did not add vitamin C for a health halo. They added it because the reaction requires it. There is a separate piece on this blog about why that single fact reorganised how I think about this whole category.

what this looks like in a normal week

You do not need jump rope and you do not need to be an athlete. The mechanism is about loading connective tissue, and walking, lifting, running, tennis, a long day on your feet all count.

If joints are your reason for being here, the practical version is a real dose of collagen with vitamin C about an hour before you move. That is it.

Worth pairing with Clark and colleagues' 24 week trial in athletes with activity related joint discomfort, which is the outcome study to Shaw's mechanism study. One shows why it should work. The other followed people for six months and found it did.

why our can is built the way it is

Twenty grams of collagen protein and vitamin C in the same cold can, which is roughly the pairing the study used, without the mixing.

An hour before you train, or an hour before whatever counts as loading in your life. And on the days you do nothing, drink it anyway, because the skin and bone and nail research was never about timing at all. It was about every day.

the research i leaned on

• Shaw G, Lee-Barthel A, Ross ML, Wang B, Baar K. Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. American Journal of Clinical Nutrition. 2017;105(1):136-143.
• Clark KL, Sebastianelli W, Flechsenhar KR, et al. 24-week study on the use of collagen hydrolysate as a dietary supplement in athletes with activity-related joint pain. Current Medical Research and Opinion. 2008;24(5):1485-1496.
• Zdzieblik D, Oesser S, Gollhofer A, König D. Improvement of activity-related knee joint discomfort following supplementation of specific collagen peptides. Applied Physiology, Nutrition, and Metabolism. 2017;42(6):588-595.

LÉS is a beverage, not medicine, and nothing here is medical advice.