Testosterone replacement and resistance exercise in HIV-infected men with weight loss and low testosterone levels

Context Previous studies of testosterone supplementation in HIV-infected me n failed to demonstrate improvement in muscle strength. The effects of resi stance exercise combined with testosterone supplementation in HIV-infected men are unknown. Objective To determine the effects of testosterone replacement with and wit hout resistance exercise on muscle strength and body composition in HIV-inf ected men with low testosterone levels and weight loss. Design and Setting Placebo-controlled, double-blind, randomized clinical tr ial conducted from September 1995 to July 1998 at a general clinical resear ch center. Participants Sixty-one HIV-infected men aged 18 to 50 years with serum test osterone levels of less than 12.1 nmol/L (349 ng/dL) and weight loss of 5% or more in the previous 6 months, 49 of whom completed the study. Interventions Participants were randomly assigned to 1 of 4 groups: placebo , no exercise (n = 14); testosterone enanthate (100 mg/wk intramuscularly), no exercise (n = 17); placebo and exercise (n = 15); or testosterone and e xercise (n = 15). Treatment duration was 16 weeks. Main Outcome Measures Changes in muscle strength, body weight, thigh muscle volume, and lean body mass compared among the 4 treatment groups. Results Body weight increased significantly by 2.6 kg (P<.001) in men recei ving testosterone alone and by 2.2 kg (P = .02) in men who exercised-alone but did not change in men receiving placebo alone (-0.5 kg; P = .55) or tes tosterone and exercise (0.7 kg; P = .08). Men treated with testosterone alo ne, exercise alone, or both experienced significant increases in maximum vo luntary muscle strength in leg press (range, 22%-30%), leg curls (range, 18 %-36%), bench press (range, 19%-33%), and latissimus pulls (range, 17%-33%) . Gains in strength in all exercise categories were greater in men assigned to the testosterone-exercise group or to the exercise-alone group than in those assigned to the placebo-alone group. There was a greater increase in thigh muscle volume in men receiving testosterone alone (mean change, 40 cm (3); P<.001 vs zero change) or exercise alone (62 cm(3); P = .003) than in men receiving placebo alone (5 cm(3); P = .70). Average lean body mass incr eased by 2.3 kg (P = .004) and 2.6 kg (P<.001), respectively, in men who re ceived testosterone alone or testosterone and exercise but did not change i n men receiving placebo alone (0.9 kg; P = .21). Hemoglobin levels increase d in men receiving testosterone but not in those receiving placebo. Conclusion Our data suggest that testosterone and resistance exercise promo te gains in body weight, muscle mass, muscle strength, and lean body mass i n HIV-infected men with weight loss and low testosterone levels. Testostero ne and exercise together did not produce greater gains than either interven tion alone.