DOES THE ACCUMULATION OF 150 MINUTES OF EXERCISE PER WEEK IMPROVE WEIGHT LOSS AND FAT LOSS IN OVERWEIGHT ADULT WOMEN?

Abstract

256 The Surgeon General's Report on Physical Activity and Health has recommended that individuals accumulate at least 30 minutes of moderate levels of physical activity on most days of the week. The purpose of this study was to examine the exercise threshold associated with improvements in weight loss in overweight adult women. One-hundred thirty nine overweight women(BMI=32.8±4.1 kg/m2, age=36.9±5.4 years) enrolled in a behavioral weight control program participated in this study. Subjects were randomized to one of three exercise groups: 1) long-bout (LB; N=46), 2) short-bout (SB; N=49), or short-bout plus home equipment (SBEQ; N=44). All groups were instructed to exercise 5 d/wk with duration progressing to 40 minutes per day. LB performed 1 exercise bout per day (1 40-min bout per day), whereas SB and SBEQ performed multiple 10 minutes bouts of exercise per day (4 10-minute bouts per day). In addition, SBEQ had a motorized treadmill placed in their homes. All subjects were instructed to reduce caloric intake to 1200-1500 kcal/day. Exercise was recorded in weekly diaries, and both body weight and body composition were assessed at baseline and 24 weeks. Body composition was assessed using dual-energy x-ray absorptiometry (Lunar DPX-L). Subjects were divided into two groups based on their mean level of weekly exercise: <150 min/wk (N=69), ≥150 min/wk (N=70). Results presented in the table showed weight loss and fat loss were significantly greater in individuals reporting at least 150 minutes of exercise per week (p<.001). These results were similar within each exercise condition (LB,SB,SBEQ) (p<.005).TableThese results suggest that the accumulation of at least 150 minutes of exercise per week may enhance weight loss and fat loss in overweight women, and developing strategies to improve adherence to this level of exercise may be advantageous. These subjects are being followed to assess the effect of this level of exercise on long-term weight loss.