||07-10-2010 04:45 AM
Changes in Hormones and Fat Oxidation with Weight Loss & Regain in Obese Adolescents.
Quite a nice little study demonstrating the beneficial effect of exercise on lipid oxidation in a weight loss program.
Changes in adipocyte hormones and lipid oxidation associated with weight loss and regain in severely obese adolescents.
OBJECTIVE: To investigate changes in adipocyte hormones and lipid oxidation during and after a weight-reduction programme in severely obese adolescents.
DESIGN: Longitudinal-clinical investigation including a 9-month multidisciplinary weight-reduction programme in a specialised institution with lifestyle education, moderate energy restriction and regular physical activity, followed by a 4-month period at home.
SUBJECTS: A total of 26 (12 boys and 14 girls) severely obese adolescents (mean BMI: 33.9 kg/m2; 41.5% fat mass (FM)).
MEASUREMENTS: Before starting (M0), at the end (M9), and 4 months after the end (M13) of the intervention blood samples were collected at fast, body composition was assessed by dual X-ray absorptiometry, and energy expenditure (EE) and substrate oxidation were assessed by whole-body indirect calorimetry over 24 h.
RESULTS: At M9, adolescents had lost 19.0% body weight (BW), 41.3% FM (P<0.001), with a minor fat free mass (FFM) loss in girls (6.4%, P<0.001) but no significant FFM changes in boys. Plasma leptin concentration at M9 was 70% lower (P<0.001), whereas plasma adiponectin concentration was 26.6% higher (P<0.001). The results also suggest that after adjustment for FFM and energy balance, sleeping and sedentary activity lipid oxidation rates were higher at M9 than at M0. At M13, plasma adiponectin, insulin, glucose and LDL concentrations returned to the initial levels, and leptin to an intermediate level in the 10 adolescents who had regained BW. Adjusted lipid oxidation rate decreased in both groups of subjects but it was not correlated to any change in plasma adipocyte hormones, which rather changed in relation to FM modifications.
CONCLUSION: Moderate energy restriction and regular moderate and high intensity physical activities in obese adolescents induced beneficial changes in BW and composition, lipid oxidation and blood parameters, especially adipocyte hormones.
|All times are GMT -7. The time now is 01:02 PM.
Powered by vBulletin® Version 3.8.9 Beta 3
Copyright ©2000 - 2015, vBulletin Solutions, Inc.