title: Effects of aerobic exercise and dietary carbohydrate on energy expenditure and body composition during weight reduction in obese women.
abstract: To test the benefits of aerobic exercise and dietary carbohydrate during reduced-energy feeding, 23 obese women (44 +/- 4% fat) were randomly assigned to either aerobic exercise (Ex) or no exercise (Nx), and to a low-fat (LF) or low-carbohydrate (LC) reducing diet (5.00 +/- 0.56 MJ/d) for 12 wk. Changes in body composition, postabsorptive resting metabolic rate (RMR), thermic effect of a meal (TEM), and total daily energy expenditure (TDEE) were measured by respiratory gas exchange and doubly labeled water. Significant effects of Ex included a greater loss of fat mass (Ex: -8.8 +/- 2.1 vs Nx: -6.1 +/- 2.3 kg, P = 0.008) and maintenance of TDEE (Ex: +0.07 +/- 1.23 vs Nx: -1.46 +/- 1.04 MJ/d, P = 0.004), due to a difference in physical activity (Ex: +0.75 +/- 1.06 vs Nx: -0.61 +/- 1.03 MJ/d, P = 0.006), which was not attributable solely to the Ex sessions. RMR in both groups decreased comparably (-0.54 MJ/d), and TEM (% of meal) did not change. Diet composition did not significantly influence body composition or energy expenditure changes, but a greater weight loss was observed after the LC than after the LF (-10.6 +/- 2.0 vs -8.1 +/- 3.0 kg, P = 0.037) diet. The addition of aerobic exercise to a low-energy diet was beneficial in the treatment of moderate obesity because of its favorable effects on body composition, physical activity, and TDEE.
authors.affiliation: Department of Medicine, University of Chicago, IL 60637.
authors.forename: S B
authors.initials: SB
authors.lastname: Racette
authors.forename: D A
authors.initials: DA
authors.lastname: Schoeller
authors.forename: R F
authors.initials: RF
authors.lastname: Kushner
authors.forename: K M
authors.initials: KM
authors.lastname: Neil
authors.forename: K
authors.initials: K
authors.lastname: Herling-Iaffaldano
mesh_terms: D000328:Adult; D001823:Body Composition; D004040:Dietary Carbohydrates / Q000494:pharmacology*; D002149:Energy Intake; D004734:Energy Metabolism; D015444:Exercise; D005260:Female; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000378:metabolism / Q000628:therapy*; D015431:Weight Loss
chemical_list: D004040:Dietary Carbohydrates