Collagen Peptide Supplementation during Training Does Not Further Increase Connective Tissue Protein Synthesis Rates.
Level 2 - randomized trial
Randomized, double-blind, parallel-group controlled trial
PubMed 39086044 · doi:10.1249/MSS.0000000000003519
What was done
In a randomized, double-blind, parallel-group trial, 25 young recreational male athletes (mean age 24 ± 3 years, body weight 76.9 ± 6.4 kg) underwent 1 week of intense resistance exercise training. Participants consumed either 15 g of hydrolyzed collagen peptides twice daily (30 g/day total) or a noncaloric placebo. Daily deuterated water ingestion along with pre- and post-intervention blood and skeletal muscle biopsy sampling was used to measure circulating amino acid concentrations and daily fractional synthesis rates of myofibrillar and muscle connective proteins.
What was found
Post-absorptive plasma concentrations of glycine, proline, and hydroxyproline rose following collagen supplementation and were significantly higher than in the placebo group (P < 0.05). Across the cohort, daily baseline muscle connective protein synthesis rates were higher than myofibrillar protein synthesis rates (1.99 ± 0.38 vs 1.34 ± 0.23%·d⁻¹; P < 0.001). Collagen peptide supplementation did not increase myofibrillar protein synthesis rates (1.34 ± 0.19%·d⁻¹ with collagen vs 1.34 ± 0.27%·d⁻¹ with placebo; P > 0.05) or muscle connective protein synthesis rates (1.97 ± 0.47%·d⁻¹ with collagen vs 2.00 ± 0.27%·d⁻¹ with placebo; P > 0.05).
Why it matters
Despite elevating plasma concentrations of collagen-precursor amino acids, supplemental collagen peptides do not augment intramuscular connective tissue or myofibrillar remodeling during short-term resistance training.
Limits
The study was restricted to a small cohort (n = 25) of young, healthy males over a short duration of 1 week. Measurements were made specifically in intramuscular connective tissue rather than discrete tendons or ligaments, and the comparator was a noncaloric placebo rather than an isonitrogenous protein control. Long-term functional adaptations and clinical outcomes were not evaluated.
Cited by
- supports Ingestion of 20 to 30 grams of collagen protein does not stimulate mixed muscle protein synthesis or intramuscular connective tissue protein synthesis.