Effects of Exercise and Diet on Body Composition and Cardiovascular Fitness in Adults with Severe Mental Retardation

Abstract

The present study evaluated the effects of an aerobic fitness program and dietary intervention with external control components (verbal reinforcement and token economy system) on three obese adults with severe mental retardation. Intervention treatment consisted of a 500-kcal daily reduction in diet under that required to maintain present body weight seven days per week and a 1 hour aerobic exercise program 5 days per week. A multiple-baseline across subjects design was employed to evaluate treatment effectiveness on three dependent measures: aerobic capacity (predicted max VO2), body weight, and percent body fat (skinfold measures). Additional subject data were gathered on percent increases on each of the dependent measures. A visual inspection of the data indicated that subjects improved from their baseline scores on all measurements. Subjects' mean body weight and percent body fat decreased 7.73% and 19.31% respectively. Mean max VO2 increased 29.8%. Results indicated that adults with severe mental retardation respond to a program of progressive aerobic exercise (e.g., brisk walking, jogging, or bicycling) and caloric restriction much the same way as their nonretarded peers. Issues relating to program effectiveness, contribution of the externally derived motivation component of the training package, and the future development of physical activity and dietary intervention programs for obese individuals with mental retardation are discussed.