HealthDay News — Exercise-induced weight loss and calorie restriction have addictive benefits, according to study findings published in Diabetes Care.
To test the hypothesis that weight loss from calorie restriction and exercise improves insulin sensitivity more than matched weight loss induced by exercise or calorie restriction alone, Edward P. Weiss, PhD, of Saint Louis University, and colleagues conducted a randomized experiment.
Sedentary, overweight male and female patients (n=52), aged 45 to 65 years, were randomly assigned to undergo 6% to 8% weight loss by calorie reduction, exercise, or a combination of calorie reduction and exercise.
During frequently sampled oral glucose tolerance tests, the scientists measured glucose, insulin, C-peptide, insulin sensitivity, and incretin hormones (glucagon-like peptide 1 [GLP-1] and glucose-dependent insulinotropic polypeptide [GIP]).
Weight losses were similar in all groups, but insulin sensitivity index values increased two-fold more in the calorie reduction and exercise group versus the calorie reduction and exercise groups. In the calorie reduction group only, postprandial GLP-1 concentrations decreased (P=0.04); in all groups, GIP concentrations decreased. There was no change in incretin effects on insulin secretion.
“These findings underscore the importance of promoting both CR and EX for optimal health,” concluded the researchers.
“However, because data from participants who withdrew from the study and from those who did not adhere to the intervention were excluded, the results may be limited to individuals who are capable of adhering to a healthy lifestyle intervention.”