Comparable effects of diet and exercise on body composition and lipoproteins in older men.Med. Sci, Sports Exerc., Vol. 26, No. 11, pp. 1307–1315, 1994. Changes in body composition, fat distribution and lipoprotein lipids in response to weight loss elicited by a 10-month program of hypocaloric diet (HD) therapy alone or combined with aerobic exercise training (AEX+HD) were examined in sedentary obese older males. Body composition was assessed by hydrodensitometry and fat distribution was evaluated with skinfold thickness and circumference measures. The HD group underwent a dietary/behavioral modification program to reduce caloric intake. The AEX+HD group underwent a similar dietary modification program combined with aerobic exercise training. Following completion of the study, 15 subjects from each group were individually pair matched based on age (57.1 ± 1.7 vs 61.3 ± 2.4 yrs) and their reduction in body mass (−7.6 ± 1.3 vs −8.0 ± 1.1 kg). Reductions in fat and fat-free mass and skinfold thickness and circumferences were similar in both groups. In both the AEX+HD and HD groups there were significant reductions in the ratio of low-density lipoproteins to high-density lipoproteins (HDL-C) and triglycerides and a significant increase in HDL2-C. There were no differences in final values or absolute and relative changes in the various lipoprotein values between the two groups. These results suggest weight loss induced by diet alone or combined with aerobic exercise cause similar changes in body composition and lipoprotein lipids.