Oral Supplementation of Specific Collagen Peptides Combined with Calf-Strengthening Exercises Enhances Function and Reduces Pain in Achilles Tendinopathy Patients

Praet SFE, Purdam CR, Welvaert M, et al. · Nutrients

Over the first three months VISA-A rose 12.6 points (95% CI 9.7-15.5) in the group taking collagen first against 5.3 (2.3-8.3) in the group taking placebo first, and the randomisation-order interaction across the whole crossover is significant (p<0.0001). By six months the two orders had arrived at the same place — 18.5 points (15.5-21.6) and 23.0 (19.9-26.1) — which is why the authors conclude the peptides may accelerate the benefit of the exercise programme rather than add to it. Tendon microvascularity, the trial's other measured outcome, fell equally in both groups: the paper reports no difference between the interventions and no evidence of a benefit on vascularisation.

Population

Patients with chronic mid-portion Achilles tendinopathy

Intervention

2.5 g specific collagen peptides (TENDOFORTE) twice daily + calf strengthening, 3 months, crossover

Comparator

Placebo + same exercise program

Limitations

A twenty-person pilot designed without a power calculation, in tendon rather than cartilage. The study was financially supported by GELITA AG, whose TENDOFORTE product was tested, and the authors declare no conflicts. Blinding was imperfect: at the crossover, 6 of 10 in one order and 4 of 10 in the other guessed their allocation correctly. Nobody returned to their pre-injury level within the trial.