Across 14 trials and 763 women, adding protein, amino acids, or creatine to exercise did not clearly increase muscle mass

What the research found

Study (systematic review and meta-analysis). A review in the International Journal of Medical Sciences (16 Apr 2026; 23(6):1933–1951; DOI 10.7150/ijms.130435) pooled 14 trials and 763 women across reproductive stages. Five trials used whole-protein supplements, six used amino acids, and three used creatine monohydrate. Together, the supplements plus exercise did not show a clear effect on skeletal muscle mass (Hedges g 0.065), appendicular lean mass (g 0.197), or fat-free mass (g 0.069). Adverse events did not rise. The authors report selective upper-body strength improvements, particularly in the creatine trials, and say exercise alone had the reliable musculoskeletal benefit. The products were mixed, so this is not a verdict on one supplement. It is a different question from the postmenopausal creatine review in this same farm, which found a small lean-mass difference at 5 grams a day or more with resistance training. Not medical advice. Not a substitute for a prescribed medicine.

Evidence level: Review of studies. This is among the stronger kinds of evidence, but one study rarely settles a question.

Read the original at International Journal of Medical Sciences