ABSTRACT
This study examines the combined effects of caloric restriction on body composition, blood lipid, and satiety in slightly overweight women by varying food density and aerobic exercise. Twenty-three women were randomly assigned to one of two groups for a four-week weight management program: the high-energy density diet plus exercise (HDE: n = 12, 22 +/- 2 yrs, 65 +/- 7 kg, 164 +/- 5 cm, 35 +/- 4 % fat) and low-energy density diet plus exercise (LDE: n = 11, 22 +/- 1 yrs, 67 +/- 7 kg, 161 +/- 2 cm, 35 +/- 4 % fat) groups. Subjects maintained a low-calorie diet (1,500 kcal/day) during the program. Isocaloric (483 +/- 26 for HDE, 487 +/- 27 kcal for LDE) but different weight (365 +/- 68 for HDE, 814 +/- 202 g for LDE) of lunch was provided. After lunch, they biked at 60% of maximum capacity for 40 minutes, five times per week. The hunger level was scaled (1: extremely hungry; 9: extremely full) at 17:30 each day. Before and after the program, the subjects' physical characteristics were measured, and fasting blood samples were drawn. The daily energy intake was 1,551 +/- 259 for HDE and 1,404 +/- 150 kcal for LDE (P > 0.05). After four weeks, the subjects' weights and % fat decreased for both LDE (-1.9 kg and -1.5%, P < 0.05) and HDE (-1.6 kg and -1.4%, respectively, P < 0.05). The hunger level was significantly higher for HDE (2.46 +/- 0.28) than for LDE (3.10 +/- 0.26) (P < 0.05). The results suggest that a low-energy density diet is more likely to be tolerated than a high-energy density diet for a weight management program combining a low-calorie diet and exercise, mainly because of a reduced hunger sensation.