Whether you're male or female, if you lift weights, you're likely to gain muscle and strength at about the same rate — even though guys usually start with more testosterone than girls.

A 12-week, double-blind, randomized controlled trial comparing muscle mass and strength gains in healthy adult males and females matched for age, training experience, and caloric intake, all undergoing identical progressive resistance training protocols, with DEXA and isometric strength testing as primary outcomes.

A prospective cohort study tracking natural muscle and strength gains over 6 months in a large, diverse sample of males and females performing unsupervised resistance training, with serial measurements of testosterone and body composition.

A meta-analysis pooling effect sizes of relative muscle and strength gains from published RCTs comparing males and females undergoing standardized resistance training protocols.

A cross-sectional analysis comparing muscle mass and strength levels in males and females with known baseline testosterone levels who have trained consistently for a fixed duration.

A case-control study comparing individuals with high vs. low testosterone levels within each sex to determine if testosterone level, not sex, predicts relative muscle gain.