Hanson, E. D., Walts, C. T., Delmonico, M. J., Yao, L., Wang, M. Q., & Hurley, B. F. (2008). Do sex or race differences influence strength training effects on muscle or fat? ACSM 55th Annual Meeting Indianapolis. Presentation number 617.

This study examined the influence of sex and race on the effects of strength training (ST) on thigh muscle volume, mid-thigh subcutaneous fat. and intermuscular fat. Previously inactive healthy Caucasian (N = 117) and African-American (N = 54) men (N = 82) and women (N = 99), aged 50-85 yrs, underwent ~10 weeks of unilateral knee extension strength training.

Training-induced increases in absolute muscle volume were greater in men than in women, although both genders increased muscle volume significantly with strength training (the relative (%) increases were similar). There were significant increases in muscle volume within race groups but no significant differences between races. There were no significant changes in subcutaneous fat or intermuscular fat whether sex and racial groups were separated or combined. Strength training did not produce any sex by race interaction for changes in muscle volume, subcutaneous fat, or intermuscular fat.

Implication. Strength training does not alter subcutaneous or intermuscular fat regardless of sex or racial differences. Men exhibit a greater muscle hypertrophic response to strength training compared to women, although the difference is small. Race does not influence this response.

Return to Table of Contents for this issue.