Research

Hormonal

Testosterone supplementation increases fat-free mass and maximal voluntary strength in hypogonadal men, regardless of whether the dose is physiologic or supraphysiologic.

If you are a man with clinically low testosterone, testosterone replacement therapy will reliably increase your muscle mass and strength. This holds true whether you are older, HIV-positive, or even if you have normal testosterone levels but take high doses. However, do not expect this to improve your endurance running or cycling performance, nor does it guarantee a reduction in falls for older adults. Consult a doctor for blood tests before considering treatment.

GoodSupportsHIGH confidence
Testosterone supplementation of HIV-infected men with low testosterone levels and of older men with normally low testosterone concentrations also increases muscle mass... Testosterone increases maximal voluntary strength in a dose-dependent manner
Shalender Bhasin et al. · Journal of Endocrinology · 2001

Why this rating

Multiple randomized, double-blind, placebo-controlled trials are cited, though some have small sample sizes or short durations.

Source

Proof of the effect of testosterone on skeletal muscle

Shalender Bhasin et al. · Journal of Endocrinology · 2001

DOI 10.1677/joe.0.1700027

narrative_reviewCited 293×
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 →