RESISTIVE TRAINING INCREASES FAT-FREE MASS AND MAINTAINS RMR DESPITE WEIGHT-LOSS IN POSTMENOPAUSAL WOMEN

Percent body fat increases with age and is often accompanied by a loss in muscle mass, strength, and energy expenditure. The effects of 16 w k of resistive training (RT) alone or with weight loss (RTWL) on stren gth (isokinetic dynamometer), body composition (dual-energy X-ray abso rptiometry), resting metabolic rate (RMR) (indirect calorimetry), and sympathetic nervous system activity (catecholamines) were examined in 15 postmenopausal women (50-69 yr). RT resulted in significant improve ments in upper and lower body strength in both groups (P < 0.01). The nonobese women in the RT group (n = 8) did not change their body weigh t or fat mass with training. In the obese RTWL group (n = 7), body wei ght, fat mass, and percent body fat were significantly decreased (P < 0.001). Fat-free mass and RMR significantly increased with training in both groups combined (P < 0.05). There were no significant changes in resting arterialized plasma norepinephrine or epinephrine levels in e ither group with training. RT increases strength with and without weig ht loss. Furthermore, RT and RTWL increase fat-free mass and RMR and d ecrease percent fat in postmenopausal women. Thus, RT may be a valuabl e component of an integrated weight management program in postmenopaus al women.