EFFECTS OF EXERCISE MODALITY ON METABOLIC-RATE AND BODY-COMPOSITION

This study was designed to investigate the effects of exercise as a st rategy for weight management in overweight women. Specifically, the ef fects of exercise modality on resting energy expenditure (REE) and bod y composition [sum of skinfolds and fat-free mass (FFM)] were examined . Participants included 41 overweight, sedentary women aged 25-49 year s who had a defined history of dieting. Experimental (n = 26) and cont rol (n = 15) participants were recruited separately. Participants in t he experimental group were randomly assigned to either an endurance- o r a resistance-training exercise class. Exercise classes designed for a sedentary population were scheduled three times per week for a durat ion of 3 months. Results indicated that exercise modality had no effec t on REE. Exercise, regardless of modality, had a significant effect o n body composition (p = 0.0001) as shown by a significant decrease in the sum of skinfolds for the two exercise groups relative to the contr ol group (p < 0.0001). No differences in fat-free mass were observed b etween groups. Regardless of modality, exercise also resulted in an in creased estimated maximum oxygen uptake (VO2max), based on a 1-mile wa lking test (p = 0.012). The pattern of weight change of the groups was different (p = 0.029) over the 3-month period. Whereas the exercise g roups maintained their weight, the control group gained weight (simila r to 2.5 kg). Thus, although exercise modality had no effect, the bene fits of exercise per se, such as decreased body fat, increased fitness level, and weight maintenance, were observed in this population.