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 .
Dose-response effect of oxygen on hyperinflation and exercise endurance in nonhypoxaemic COPD patients.
Dynamic hyperinflation contributes to exertional breathlessness and reduced exercise tolerance in chronic obstructive pulmonary disease ( COPD ) patients . This study examined whether oxygen supplementation results in a dose-dependent decrease in hyperinflation associated with functional and symptomatic improvement . Ten severe COPD patients without clinical ly significant oxygen ( O2 ) desaturation during exercise , and seven healthy subjects , performed five exercise tests at 75 % of maximally tolerated work rate . Inspired oxygen fraction ( FI , O2 ) was varied ( 0.21 , 0.3 , 0.5 , 0.75 and 1.0 ) among tests in a r and omized order . Ventilation ( V'E ) was measured , and end-inspiratory ( EILV ) and end-expiratory ( EELV ) lung volume changes were assessed from inspiratory capacity manoeuvres . In the patients , compared to room air , endurance time increased with FI , O2=0.3 ( mean+/-SEM 92+/-20 % ) and increased further with FI , O2=0.5 ( 157+/-30 % ) . At isotime , compared to room air , there were significant reductions in dyspnoea score , EELV , EILV , V'E and respiratory frequency ( fR ) with FI , O2=0.3 . Improved endurance time negatively correlated with change in EELV ( r=0.48 , p=0.002 ) and EILV ( r=0.43 , p=0.005 ) . The dyspnoea rating decrease correlated with fR decrease . In healthy subjects , smaller V'E and fR decreases were observed at FI , O2=0.5 , accompanied by more modestly increased endurance .  Oxygen supplementation during exercise induced dose-dependent improvement in endurance and symptom perception in nonhypoxaemic chronic obstructive pulmonary disease patients , which may be partly related to decreased hyperinflation and slower breathing pattern . This effect is maximized at an inspired oxygen fraction of 0.5
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 .