Effects of Intermittent Dieting During Resistance Training in Women IV: Quality of Life

Abstract

Dieting has been reported to reduce resting energy expenditure thereby increasing the prevalence of weight gain after weight loss. Intermittent dieting during a weight loss and exercise program may help minimize these adverse effects. PURPOSE: To examine the efficacy of diet cycling with varying macronutrient diet compositions during an exercise and weight loss program on weight loss, markers of health, and fitness. METHODS: 43 overweight and sedentary women (35±8 yr; 89±18 kg; 43±4% fat, 33±6 kg/m2) were assigned to a high carbohydrate (HC, n=23) or high protein (HP, n=20) diet group. During the first 30-days, subjects consumed 1,200 kcals/d for 1-wk followed by ingesting 1,500 kcals/d for 3-wks. Subjects then followed a 2,200 kcals/d maintenance diet for 4-wks before repeating the 30-day diet. Diets were 45:30:25% or 30:45:25% carbohydrate, protein and fat, respectively, for the HC and HP groups, respectively. Subjects also participated in the Curves™ circuit training program 3-d/wk and walked briskly for 30-min 3-d/wk. The SF-36 Quality of Life (QOL) long-version psychosocial inventory was obtained at each testing interval. Data were analyzed by MANOVA with repeated measures and are presented as percent change from baseline after 1, 2, 3, 4, and 5 months respectively. RESULTS: Training and dieting improved Physical Functioning (6.4, 8.3, 9.5, 10.7, 9.5%, p<0.001); Role-Physical (9.8, 9.5, 11.0, 6.9, 10.1%, p=0.05); Role-Emotional (4.7, 7.9, 11.2, 10.4, 10.8%, p=0.001); Vitality (11.4, 10.5, 11.0, 10.5, 10.5%, p=0.04); Mental Health (10.8, 11.7, 11.9, 12.6, 10.0%, p=0.004); Bodily Pain (5.1, 5.2, 5.8, 5.9, 8.1%, p=0.014); and, General Health (6.9, 8.9, 7.6, 7.1, 7.4%, p=0.04). However, no significant differences were seen in Social Functioning (1.8, -0.6, -3.0, -3.0, -1.2%, p=0.31). In addition, no significant differences were observed between diets on QOL when diets were 45:30:25% or 30:45:25% carbohydrate, protein, and fat, respectively. CONCLUSION: Short-term diet cycling during a weight loss and exercise program improves markers of QOL. Diet had no influence when both diets were greater than 30% protein. Supported by Curves International, Waco, TX