Intramuscular TRT is more effective than transdermal formulations at increasing LBM and improving muscle strength  in middle-aged and older men , particularly in the lower extremities
BACKGROUND Inconsistent fat-free mass ( FFM ) and muscle strength responses have been reported in r and omized clinical trials ( RCTs ) administering  testosterone replacement therapy ( TRT ) to middle-aged and older men .
Our objective was to conduct a meta- analysis to determine whether TRT improves FFM and muscle strength in middle-aged and older men and whether the muscular responses vary by TRT administration route .
The effects of growth hormone and/or testosterone in healthy elderly men: a randomized controlled trial.
CONTEXT Declines in GH and testosterone ( Te ) secretion may contribute to the detrimental aging changes of elderly men . OBJECTIVE To assess the effects of near-physiological GH with/without Te administration on lean body mass , total body fat , midthigh muscle cross-section area , muscle strength , aerobic capacity , condition-specific quality of life ( Age-Related Hormone Deficiency-Dependent Quality of Life question naire ) , and generic health status ( 36-Item Short-Form Health Survey ) of older men . DESIGN , SETTING S , AND PARTICIPANTS A 6-month , r and omized , double-blind , placebo-controlled trial was performed on 80 healthy , community-dwelling , older men ( age , 65 - 80 yr ) . INTERVENTIONS Participants were r and omized to receive 1 ) placebo GH or placebo Te , 2 ) recombinant human GH ( rhGH ) and placebo Te ( GH ) , 3 ) Te and placebo rhGH ( Te ) , or 4 ) rhGH and Te ( GHTe ) . GH doses were titrated over 8 wk to produce IGF-I levels in the upper half of the age-specific reference range . A fixed dose of Te ( 5 mg ) was given by transdermal patches . RESULTS Lean body mass increased with GHTe ( P = 0.008 ) and GH ( P = 0.004 ) , compared with placebo . Total body fat decreased with GHTe only ( P = 0.02 ) . Midthigh muscle ( P = 0.006 ) and aerobic capacity ( P < 0.001 ) increased only after GHTe . Muscle strength changes were variable ; one of six measures significantly increased with GHTe . Significant treatment group by time interactions indicated an improved Age-Related Hormone Deficiency-Dependent Quality of Life question naire score ( P = 0.007 ) in the GH and GHTe groups . Bodily pain increased with GH alone , as determined by the Short-Form Health Survey ( P = 0.003 ) . There were no major adverse effects . CONCLUSION Coadministration of low dose GH with Te result ed in beneficial changes being observed more often than with either GH or Te alone
Intramuscular TRT is more effective than transdermal formulations at increasing LBM and improving muscle strength  in middle-aged and older men , particularly in the lower extremities
BACKGROUND Inconsistent fat-free mass ( FFM ) and muscle strength responses have been reported in r and omized clinical trials ( RCTs ) administering  testosterone replacement therapy ( TRT ) to middle-aged and older men .
Our objective was to conduct a meta- analysis to determine whether TRT improves FFM and muscle strength in middle-aged and older men and whether the muscular responses vary by TRT administration route .