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 .
The effect of testosterone aromatization on high-density lipoprotein cholesterol level and postheparin lipolytic activity.
Stanozolol , an oral 17 alpha-alkylated and rogen , increases hepatic triglyceride lipase activity ( HTGLA ) and decreases high-density lipoprotein cholesterol ( HDL-C ) levels , whereas intramuscular testosterone has comparatively little effect . In the present study , we tested the hypothesis that aromatization of and rogen to estrogen blunts the lipid and lipase effects of exogenous testosterone . Fourteen male weightlifters received testosterone enanthate ( 200 mg/wk intramuscularly ) , the aromatase inhibitor testolactone ( 250 mg four times per day ) , or both drugs together in a r and omized cross-over design . Serum testosterone level increased during all three drug treatments , whereas estradiol level increased only with testosterone alone ( + 47 % , P < .05 ) , demonstrating that testolactone effectively inhibited testosterone aromatization . Testosterone decreased HDL-C(-16 % , P < .05 ) , HDL2-C(-23 % , NS ) , and apoprotein ( apo ) A-I ( -12 % , P < .05 ) levels , effects that were consistently but not significantly greater with simultaneous testosterone and testolactone administration ( HDL-C , -20 % ; HDL2-C , -30 % ; apo A-I , -15 % ; P < .05 for all ) . In contrast , both testosterone regimens decreased HDL3-C levels by 13 % ( P < .05 for both ) . HTGLA increased 21 % during testosterone treatment and 38 % during combined testosterone and testolactone treatment ( P < .01 for both ) . Lipoprotein lipase activity ( LPLA ) increased only during combined testosterone and testolactone treatment ( + 31 % , P < .01 ) , suggesting that estrogen production may counteract the effects of testosterone on LPLA . Testolactone alone had little effect on any lipid , lipoprotein , apoprotein , or lipase concentration . ( ABSTRACT TRUNCATED AT 250 WORDS
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 .