Addition of aerobic exercise to dietary weight loss preferentially reduces abdominal adipocyte size

Objective: To determine if hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise differentially influence subcutaneous abdominal and gluteal adipocyte size in obese individuals. Design: Longitudinal intervention study of hypocaloric diet, diet plus low-intensity exercise, and diet plus high-intensity exercise (calorie deficit 2800 kcal/week, 20 weeks). Subjects: Forty-five obese, middle-aged women (BMI 33.0 +/- 0.6 kg/m(2), age 58 +/- 1 years). Measurements: Body composition testing and adipose tissue biopsies were conducted before and after the interventions. Subcutaneous abdominal and gluteal adipocyte size was determined. Results: All three interventions reduced body weight, fat mass, percent fat, and waist and hip girths to a similar degree. Diet only did not change subcutaneous abdominal adipocyte size, whereas both diet plus exercise groups significantly reduced abdominal adipocyte size. Changes in abdominal adipocyte size in the diet plus exercise groups were significantly different from that of the diet group. Gluteal adipocyte size decreased similarly in all three groups. Conclusion: Addition of exercise training to dietary weight loss preferentially reduces subcutaneous abdominal adipocyte size in obese women. This may be of importance for the treatment of health complications associated with subcutaneous abdominal adiposity.