Effects of specific collagen peptide supplementation combined with resistance training on Achilles tendon properties

Jerger S, Centner C, Lauber B, Seynnes O, Sohnius T, Jendricke P, Oesser S, Gollhofer A, König D · Scandinavian Journal of Medicine & Science in Sports

The strongest positive tendon result: Achilles tendon cross-sectional area rose 11.0% on collagen against 4.7% on placebo (p=0.002), with greater plantar flexor muscle thickness too (p=0.014). Read the omission though — tendon STIFFNESS and muscle strength increased in both groups with no significant difference, so the tissue got bigger without measurably performing better.

Population

Healthy male volunteers, mean age 26, completing a 14-week high-load resistance training programme

Intervention

5 g specific collagen peptides daily

Comparator

5 g placebo, same training

Limitations

Healthy young men, so it tests augmentation of normal training adaptation rather than repair. Co-author Oesser is at the Collagen Research Institute, the GELITA-linked arm. Directly contradicted on mechanical outcomes by the independent 15-week MRI trial (pmid-37436929), which found nothing on either size or stiffness.