Research

Hormonal

Testosterone administration increases muscle strength and mass by enhancing protein synthesis and promoting satellite cell-mediated myonuclear accretion.

Testosterone significantly boosts muscle growth and strength by increasing protein synthesis and adding new nuclei to muscle fibers via satellite cells. This effect is dose-dependent and more pronounced in type I fibers. While effective for enhancement, it carries significant health risks and is banned in sports.

GoodSupportsHIGH confidence
Both long-term and short-term steroid usage accentuates the degree of fibre hypertrophy in human skeletal muscle by enhancing protein synthesis. A mechanism by which testosterone facilitates the hypertrophy of muscle fibres is the activation of satellite cells and the promotion of myonuclear accretion when existing myonuclei become unable to sustain further enhancement of protein synthesis.
Fawzi Kadi · British Journal of Pharmacology · 2008

Why this rating

The paper synthesizes multiple controlled human studies and observational data on steroid users, though it acknowledges some long-term consequences are unknown.

Source

Cellular and molecular mechanisms responsible for the action of testosterone on human skeletal muscle. A basis for illegal performance enhancement

Fawzi Kadi · British Journal of Pharmacology · 2008

DOI 10.1038/bjp.2008.118

narrative_reviewCited 199×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →