Whey protein but not collagen peptides stimulate acute and longer-term muscle protein synthesis with and without resistance exercise in healthy older women: a randomized controlled trial

Oikawa SY, Kamal MJ, Webb EK, McGlory C, Baker SK, Phillips SM · The American Journal of Clinical Nutrition

The highest collagen dose ever given in a controlled human trial, at 60 g/day. Muscle protein synthesis rose with whey both at rest and after exercise; with collagen it rose only in the exercised leg acutely and was not significantly above baseline over six days in either leg. Between-protein differences favoured whey at every comparison (P<0.001 for the longer-term measure).

Population

Healthy older women, mean age 69

Intervention

30 g collagen protein TWICE daily — 60 g/day — for 6 days, with unilateral resistance exercise

Comparator

30 g whey protein twice daily

Limitations

Muscle protein synthesis, not connective tissue and not cartilage, so this bounds the protein-quality claim rather than the joint claim. Eleven women per group, six days. CIHR-funded at McMaster; the senior author reports research funding and honoraria from the US National Dairy Council and Dairy Farmers of Canada, and the comparator is whey.