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 .
Difficulties in measuring the effect of testosterone replacement therapy on muscle function in older men.
Muscle wasting in older men may be related to and rogen deficiency . We have assessed the effect of testosterone replacement therapy on muscle function in the upper and lower limbs of older ( age > 60 years ) men with blood testosterone levels < 14 nmol/L. Subjects ( n = 7 per group ) received testosterone enanthate 200 mg i.m . or placebo every 2 weeks in a double blind study over a 12-week period and underwent muscle testing every 4 weeks . A significant increase in blood levels of testosterone and a reduction in levels of sex hormone binding globulin occurred in the treatment group . Total body mass , haemoglobin and packed cell volume also increased significantly ( p < 0.05 ) . No improvements in h and grip strength , isometric strength of knee flexors and extensors or leg extensor power were seen in either group . Wide variability in all measures of muscle function were observed in these elderly men suggesting that very large study groups would be required to determine potential treatment benefits on muscle function
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 .