“Collagen builds muscle as effectively as whey.”
Collagen does not build muscle as well as whey in trials that compared similar amounts.
If your goal is building muscle, collagen is not a like-for-like swap for whey. Whey has the best support for raising muscle building, and pea protein did better than collagen in one short trial.
If you are buying a protein powder to build muscle, choose whey rather than collagen. If you avoid dairy, pea protein raised muscle building in one short trial.
Trials that gave similar amounts of collagen and whey found that whey raised muscle building more, and in one 10-week training trial whey built more muscle size. A 2026 network review ranked collagen highly, but that ranking rests on indirect comparisons, and the direct trials are small, so confidence is limited.
Collagen does not build muscle as well as whey in trials that compared similar amounts. In head-to-head studies, whey raised the body's muscle-building rate more, and in a 10-week training trial it increased muscle size more. The grain of truth is that collagen still built some muscle in that trial, and strength gains were similar in both groups.
In 22 young adults training for 10 weeks, 35 grams a day of whey increased thigh muscle thickness by 8.4% versus 5.6% with collagen matched for leucine, and upper-arm muscle by 10.1% versus 6.0%. In 22 older women taking 30 grams twice a day for six days, whey raised muscle building at rest and after exercise, while collagen did not raise longer-term rates above baseline. In 31 older men, an extra 50 grams a day of whey or pea protein raised muscle building, but collagen did not. Short-term muscle-building rates are not the same as long-term muscle growth. A 2026 network review of 78 studies ranked collagen above whey, but it compared results across different studies rather than within the same trials.
- Jacinto JL, Nunes JP, Gorissen SHM, Capel DMG, Bernardes AG, Ribeiro AS, Cyrino ES, Phillips SM, Aguiar AF. Whey Protein Supplementation Is Superior to Leucine-Matched Collagen Peptides to Increase Muscle Thickness During a 10-Week Resistance Training Program in Untrained Young Adults. International Journal of Sport Nutrition and Exercise Metabolism. 2022;32(3):133-143. DOI: 10.1123/ijsnem.2021-0265. PMID: 35042187
- Oikawa SY, Kamal MJ, Webb EK, McGlory C, Baker SK, Phillips SM. 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. American Journal of Clinical Nutrition. 2020;111(3):708-718. DOI: 10.1093/ajcn/nqz332. PMID: 31919527. PMCID: PMC7049534
- McKendry J, Lowisz CV, Nanthakumar A, MacDonald M, Lim C, Currier BS, Phillips SM. The effects of whey, pea, and collagen protein supplementation beyond the recommended dietary allowance on integrated myofibrillar protein synthetic rates in older males: a randomized controlled trial. American Journal of Clinical Nutrition. 2024;120(1):34-46. DOI: 10.1016/j.ajcnut.2024.05.009. PMID: 38762187. PMCID: PMC11291473
- Drummond MDM, Silva RAD, Junior NC, Melo MS, Ferreira MHL. Which Protein-Based Dietary Supplements Most Effectively Enhance Fat-Free Mass and Strength Gains in Healthy Adults Undergoing Resistance Training? A Network Meta-Analysis. Translational Sports Medicine. 2026;2026:5557511. DOI: 10.1155/tsm2/5557511. PMID: 41635649. PMCID: PMC12862422