Bhasin S, Storer TW, Berman N, Callegari C, Clevenger B, Phillips J, Bunnell TJ, Tricker R, Shirazi A, Casaburi R
New England Journal of Medicine
July 1996
RCT
43 participants
Abstract
Athletes often take anabolic steroids in an attempt to enhance performance. Although many reports of steroid use are anecdotal, the actual physiological and psychological effects have not been rigorously studied. We designed a randomized study to determine whether supraphysiologic doses of testosterone, when administered with or without exercise, increase muscle size and strength.
Methodology
We randomly assigned 43 normal men to one of four groups: placebo with no exercise, testosterone with no exercise, placebo plus exercise, and testosterone plus exercise. The men received injections of 600 mg of testosterone enanthate or placebo weekly for 10 weeks. The men in the exercise groups performed standardized weight-lifting exercises three times weekly.
Results
Testosterone treatment increased fat-free mass by 3.2 kg in the no-exercise group and 6.1 kg in the exercise group. Muscle size increased significantly. The testosterone-plus-exercise group showed the greatest increases in strength across all measures. Triceps and quadriceps cross-sectional areas increased significantly.
Conclusions
Supraphysiologic doses of testosterone, especially when combined with strength training, increase fat-free mass, muscle size, and strength in normal men.