Acute exercise increases GH release, BMR, and diet induced thermogensis; improves insulin sensitivity and postprandial lipemia; and reduces nocturnal serum leptin. These responses may be altered in the obese. Recent data suggest that bouts of exercise spread throughout the day may be more effective than a single bout of exercise if total duration is the same. We will evaluate the effects of a single-session vs. multiple sessions of exercise on the aforementioned variables in normal weight and obese subjects.