Alterations In Body Composition, Lipid Profiles And Inflammatory Mediators Based On Leptin Levels Following Exercise Training

Abstract

Many studies have shown that leptin levels are correlated with percent body fat and body mass index. It is well documented that regular exercise reduces leptin levels in obese individuals altering in body fat, body weight and inflammatory factors. However, it is not clear whether regular exercise can affect blood lipid profiles and inflammatory factors among non-obese individuals with leptin levels above or below normal. PURPOSE: To investigate the effect of blood leptin levels on body composition, lipid profiles and inflammatory mediators following 8 week exercise training. METHODS: Total 53 healthy male subjects were recruited in the study and 22 subjects whose percent body fat was normal range (16∼20%) were eligible for either low leptin level (2.03+0.29ng/ml, n=12, LLEG) or high leptin level(5.77+0.56ng/ml, n=10, HLEG). Both groups performed 5 day-walking (30∼50 min with 50% HRR) and 3 day-resistant exercise including leg press, chest press, lateral pull down, leg extension, leg curl, abdomen curl, back extension, biceps curl, and triceps curl at the intensity of 50∼80% 1RM for 8 weeks. One-way ANOVA repeated measures was used to determine group by time effect among variables. RESULTS: A significant decrease was shown in leptin levels in HLEG compared to LLEG(40.21% vs. 21.18%, p < 0.01) following 8 weeks. There was a significant decrease in body weight in HLEG compared to LLEG(3.47% vs. 0.59%, p<0.05) but no significant differences showed in percent body fat (9.95% vs. 7.92%, p=0.28). Although there were significant decreases in triglyceride(24.47% vs. 19.83%), total cholesterol(13.29% vs. 6.76%), and low density lipoprotein(11.55% vs. 11.52%) in both groups following 8 week, there were no statistically differences in group by time effect. No significant difference was shown in TNF-a(15.70% vs. 17.88%) but there was a significant decrease in IL-6 in HLEG compared to LLEG(27.78% vs. 2.47%, p<0.05). CONCLUSIONS: Regular exercise changed body composition, lipid profiles and inflammatory factors but may be more useful modifier to prevent obese-related symptoms when the leptin level is high.