Conclusions and Relevance This systematic review and meta- analysis did not show a significant beneficial or detrimental association of HT with muscle mass .
Importance Hormone therapy ( HT ) has been suggested for protection against age-related muscle weakness in women .
However , the potential for HT-associated health risks necessitates a better underst and ing of the direction and magnitude of the association between HT and health outcomes , such as lean body mass ( LBM ) .
Objective To determine whether HT was associated with reduced LBM loss compared with not receiving HT  among postmenopausal women aged 50 years and older .
Effects of exercise training and hormone replacement therapy on lean and fat mass in postmenopausal women.
BACKGROUND Menopause is associated with decreases in lean mass and increases in fat mass . Serum hormone levels and hormone replacement therapy ( HRT ) may modify the effects of exercise training on body composition in postmenopausal women . METHODS We assessed the changes in total body and regional lean soft tissue and fat mass ( using dual-energy x-ray absorptiometry ) in 94 sedentary postmenopausal women , aged 40 - 65 years , after 12 months of resistance and weight-bearing aerobic exercise training . Women currently on oral HRT ( n = 39 ) and not on HRT ( n = 55 ) were r and omized within groups to exercise and no exercise , result ing in four groups : exercise + HRT ( n = 20 ) , HRT ( n = 22 ) , exercise ( n = 24 ) , and control ( n = 28 ) . Fasting blood sample s were measured for resting serum total levels of estrone , estradiol , cortisol , and rostenedione , growth hormone , and insulin-like growth factor 1 at baseline and 12 months . RESULTS We found significant effects of exercise on increases in total body , arm , and leg lean soft tissue mass , and decreases in leg fat mass and percentage of body fat . There were no interaction effects of exercise and HRT on the changes in muscle strength and body composition . No significant changes in total hormone levels were found after 12 months . CONCLUSIONS Exercise training result ed in significant beneficial changes in lean soft tissue and fat mass in early postmenopausal women . These changes in body composition were neither influenced by prolonged HRT use nor accompanied by changes in total levels of the hormones determined in this study
Conclusions and Relevance This systematic review and meta- analysis did not show a significant beneficial or detrimental association of HT with muscle mass .
Importance Hormone therapy ( HT ) has been suggested for protection against age-related muscle weakness in women .
However , the potential for HT-associated health risks necessitates a better underst and ing of the direction and magnitude of the association between HT and health outcomes , such as lean body mass ( LBM ) .
Objective To determine whether HT was associated with reduced LBM loss compared with not receiving HT  among postmenopausal women aged 50 years and older .