Dehydroepiandrostrone (DHEA) and its sulfated ester (DHEAS) are high circulating weak androgens which have been associated with conditions that accompany age-related decline such as sarcopenia, hyperinsulinemia, osteopenia, and cardiovascular disease. The decline in DHEA with age is particularly marked in postmenopausal women. Exercise has always been advocated in women; benefit has been demonstrated inmuscle, bone and lipid physiology, as well as perception of energy and sense of well-being. This study aims to explore the combined effect of both DHEA and exercise in postmenopausal women, age range 55-75 years old. Subjects will receive DHEA (50mg/day) or placebo for a 12-week period. At the beginning and conclusion of the study patients will undergo testing for muscle strength, body composition, VO2 max, insulin sensitivity, muscle biopsy with mitochondria enzyme measurements, and psychological analysis. Blood samples pre and post intervention will also be obtained and the level of selected anabolic markers, lipids, and androgenic and sex steroid levels will be assessed. For the twelve-week period, both placebo and DHEA treated participants will be involved in a resistance and aerobic exercise program coordinated through the GCRC and the Dan Abraham Healthy Living Center. Several correlations have been established with respect to exogenous DHEA administration in postmenopausal women. None have evaluated oral DHEA therapy in the setting resistance and aerobic exercise, key therapies advocated in postmenopausal women. As a plausible anabolic hormone DHEA is hypothesized to accentuate the effects of exercise as has been shown for testosterone. This study, as a randomized double-blind placebo controlled trial, will investigate the effects, if any, of a regimented exercise program and DHEA supplementation in postmenopausal women, specifically for evidence of enhancement of exercise effect by oral supplementation with DHEA in attenuating age-related decline