The Effects of Exercise Training on Resting Metabolic Rate in Youth with Overweight or Obesity

Resting metabolic rate (RMR) is the largest component in energy expenditure and is often reduced with weight loss. Exercise training has been shown to attenuate RMR reductions in adults. However, little is known about the effects of exercise training and body composition changes on RMR in youth with overweight or obesity. A secondary analysis of sedentary youth (18 years, BMI percentile > 85%), randomly assigned to either a control group or one of 3 exercise intervention groups: aerobic, resistance or combined, was conducted. Absolute RMR change did not differ between exercise modalities compared to control. Changes in fat free mass (FFM), but not fat mass, visceral fat or skeletal muscle was significantly associated with changes in RMR independent of exercise modality. Thus, in youth with overweight or obesity, although exercise modality was not associated with different changes in RMR, FFM change appears to be a modest predictor of RMR change.