Regular exercise and the age-related decline in resting metabolic rate in

A low resting metabolic rate (RMR) is a risk factor for future weight gain. We tested the hypothesis that the age-related decline in RMR in sedentary women is not observed in women who exercise regularly. Sixty-five healthy, weight-stable women, aged 21–35 or 50–72 yr, were studied: 12 premenopausal and 15 postmenopausal sedentary women, 13 premenopausal and 15 postmenopausal distance runners, and 10 endurance-trained postmenopausal swimmers. RMR was measured by indirect calorimetry (ventilated hood system) after an overnight fast, and values were adjusted for fat mass and fat-free mass (RMRadj). The RMRadj was;10 % lower in the postmenopausal vs. premenopausal sedentary women (52 6 2 vs. 57 6 2 Cal/h; P, 0.002). In contrast, RMRadj was not significantly different in the premenopausal (59 6 2 Cal/h) and postmenopausal (57 6 1 Cal/h) distance runners. The postmenopausal swimmers had a RMRadj (57