Exercise responses in females with anorexia nervosa

Abstract

Exercise responses were evaluated in 42 primary anorexic females (Pri-AN; mean age 18.8 years) and 33 bulimic females (Bul-AN; mean age 19.7 years) and compared with 14 healthy unconditioned lean females (Lean Control; mean age 19.6 years). All subjects performed isometric handgrip at 50% of maximum voluntary contraction (MVC) for 90 seconds and treadmill exercise to subjective exhaustion (Balke Protocol). Resting heart rate (HR) and blood pressure (BP) were not different in the three groups. Maximal grip strength and 90 second isometric handgrip systolic blood pressure (SBP) was significantly lower (p <.05) in Pri-AN compared with Bul-AN and Lean Controls. With treadmill exercise, maximal HR and BP were similar for all groups. However, estimated treadmill work capacity (METs) for Pri-AN (10.7 ± 3) and Bul-AN (10 ± 8.3) was significantly lower (p <.05) than lean Control subjects (12.3 ± 3). There was a positive correlation between maximal SBP and body weight (wt), percent body fat (% fat) and lean body mass (LBM). These findings indicate that Pri-AN and Bul-AN are associated with a substantial reduction in aerobic capacity. The attenuated BP response to exercise seen in both anorexia groups appears to be a general function of tissue mass and may be an appropriate adaptation to weight loss.