Does Collagen Supplementation Support Musculoskeletal Recovery? A Narrative Review of Tendom, Ligament and Muscle Adaptation

Abstract

Introduction and aim: Collagen accounts for ~1/3 of body protein and forms the structural core of tendons, ligaments, and skeletal muscle extracellular matrix (ECM). Oral hydrolyzed collagen or collagen peptide (CP) supplementation has gained popularity, yet clinical evidence lags marketing claims. Results vary, several trials report null effects, and key questions on dosing, tissue specificity, and cofactors such as vitamin C remain open. This review critically appraises CP effects on tendon morphology and mechanics, ligament remodeling, and post-exercise muscle recovery. Material and method: Searches (April 2026) covered PubMed, Scopus, Web of Science, and Google Scholar. Terms included: collagen peptides, hydrolyzed collagen, tendon remodeling, ligament, exercise-induced muscle damage, DOMS, ECM, and musculoskeletal health. English-language RCTs, systematic reviews, and meta-analyses were prioritized. Results: For tendons, trials report increased cross-sectional area (CSA) and stiffness with 15–30 g/day CP combined with resistance or plyometric training. However, at least two RCTs found no effect on mechanical properties and certainty of evidence is low-to-moderate. Human ligament data are lacking as the field relies on in vitro and biomarker studies. Muscle recovery data are contradictory: some trials show attenuated creatine kinase release and improved neuromuscular function while stable isotope tracer studies found no rise in intramuscular connective protein synthesis after CP ingestion, undermining the proposed mechanism. Conclusions: Evidence for collagen supplementation in musculoskeletal health is weaker than its commercial prominence suggests. A modest signal for tendon CSA exists, but mechanical effects are inconsistent. For ligament repair and muscle recovery, evidence is indirect or negative. Broad recommendations are premature. Future RCTs need longer interventions, female populations, active protein controls, and clinically meaningful endpoints.