Research

Hormonal

BCAA supplementation activates anabolic signaling pathways (mTORC1) and improves hormonal profiles (testosterone/cortisol ratio) in the short term, but this does not translate to long-term muscle or strength gains if total protein intake is adequate.

BCAAs do trigger muscle-building signals in your body, but this doesn't mean you will gain muscle or strength. If you are eating enough protein from food, BCAAs add no value. Do not use them to try to 'boost' your muscle growth.

GoodQualifiesHIGH confidence
Although BCAAs tended to activate anabolic signals, the benefits on performance and body composition were negligible.
Diogo V. Martinho et al. · Nutrients · 2022

Why this rating

Based on systematic review of molecular and hormonal studies.

Source

Oral Branched-Chain Amino Acids Supplementation in Athletes: A Systematic Review

Diogo V. Martinho et al. · Nutrients · 2022

DOI 10.3390/nu14194002

systematic_reviewCited 57×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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