The present analysis provides an estimate of the average treatment effects of testosterone therapy in middle-aged men .
OBJECTIVES Ageing in men is associated with a gradual decline in serum testosterone levels and a concomitant loss of muscle mass , accumulation of central adiposity , impaired mobility and increased risk of bone fractures .
Whether and rogen treatment might be beneficial in these subjects is still under debate .
We have carried out a systematic review of r and omized controlled trials ( RCTs ) evaluating the effects of testosterone ( T ) administration  to middle-aged and ageing men on body composition , muscle strength , bone density , markers of bone metabolism and serum lipid profile .
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 men failed to demonstrate improvement in muscle strength . The effects of resistance exercise combined with testosterone supplementation in HIV-infected men are unknown . OBJECTIVE To determine the effects of testosterone replacement with and without resistance exercise on muscle strength and body composition in HIV-infected men with low testosterone levels and weight loss . DESIGN AND SETTING Placebo-controlled , double-blind , r and omized clinical trial conducted from September 1995 to July 1998 at a general clinical research center . PARTICIPANTS Sixty-one HIV-infected men aged 18 to 50 years with serum testosterone 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 r and omly 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 exercise ( 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 receiving 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 testosterone and exercise ( 0.7 kg ; P = .08 ) . Men treated with testosterone alone , exercise alone , or both experienced significant increases in maximum voluntary 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 cm3 ; P<.001 vs zero change ) or exercise alone ( 62 cm3 ; P = .003 ) than in men receiving placebo alone ( 5 cm3 ; P = .70 ) . Average lean body mass increased by 2.3 kg ( P = .004 ) and 2.6 kg ( P<.001 ) , respectively , in men who received testosterone alone or testosterone and exercise but did not change in men receiving placebo alone ( 0.9 kg ; P = .21 ) . Hemoglobin levels increased in men receiving testosterone but not in those receiving placebo . CONCLUSION Our data suggest that testosterone and resistance exercise promote gains in body weight , muscle mass , muscle strength , and lean body mass in HIV-infected men with weight loss and low testosterone levels . Testosterone and exercise together did not produce greater gains than either intervention alone
The present analysis provides an estimate of the average treatment effects of testosterone therapy in middle-aged men .
OBJECTIVES Ageing in men is associated with a gradual decline in serum testosterone levels and a concomitant loss of muscle mass , accumulation of central adiposity , impaired mobility and increased risk of bone fractures .
Whether and rogen treatment might be beneficial in these subjects is still under debate .
We have carried out a systematic review of r and omized controlled trials ( RCTs ) evaluating the effects of testosterone ( T ) administration  to middle-aged and ageing men on body composition , muscle strength , bone density , markers of bone metabolism and serum lipid profile .