RESUMO
This study examined the effects of interval training on serum levels of leptin, cortisol, testosterone, growth hormone [GH]and insulin resistance index [HOMA-IR] in young overweight/ obese men. Eighteen previously sedentary, overweight/ obese men [BMI=31.2 +/- 3.33 Kg/m2, mean age 20 y- 3 mo] in two, the experimental and control groups, participated in 16 weeks of moderate to high intensity interval training [8-10 x 4 minutes sets of running at 60-90% of Reserve Heart Rate and 2 minutes rest interval at 40-50% of Reserve Heart Rate], three days per week. Serum levels of leptin, cortisol, testosterone, insulin, GH and HOMA-IR, and anthropometric indices were measured before and 48 hours after the last training session. Statistical analysis was done by paired and independent t-test and Pearson correlation, P value<0.05 being considered significant. Interval training resulted in decreased in levels of leptin [P=0.007] and anthropometric indices such as body fat percent, body fat mass, waist circumference and waist - to- hip ratio [P<0.05]; testosterone and cortisol levels increased following interval training [P<0.05]. However, no significant correlation was found between primary levels and alterations in leptin levels and the anthropometric indices assessed [P>0.05]. Moderate to high intensity interval training improves lipid metabolism via regulating leptin, testosterone and cortisol levels and body composition, in young overweight/ obese men, changes that may not be in line with changes occuring in insulin and GH.
RESUMO
Intracellular adhesion molecule-1 is one of the factors associating obesity and inflammatory lesions like atherosclerosis. This study examined the effects of resistance [R] and endurance [E] training on serum levels of slCAM-1 and lipid profiles in sedentary obese women. Participants included 24 [8 control, 8 RT and 8 ET] obese [BMI>30] women, studied before and after 10 weeks of resistance training [40-60% of 1RM] and swimming endurance training [at 50-60% of HRmax], 3 days/week. Serum levels of slCAM-1, lipid profiles and anthropometric indices were measured at baseline and again 48 hours after training. Statistical analysis was done by paired t-test. ANOVA and Pearson correlation, and P value<0.05 was considered significant. Levels of slCAM-1 [P=0.042], cholesterol [P=0.006] and HDL-C [P=0.006] changed significantly following 10 weeks of endurance and resistance training compared to those of the control group. There was significant decrease in serum levels of slCAM-1 in the both RT [P=0.012, 21.7%] and ET groups [P=0.017, 18.4%]. Although significant changes did not exist in lipid profiles after resistance training [p>0.05], TG [P=0.001], cholesterol [P=0.043] and HDL-C [P=0.002] changed significantly in the endurance training group. Hence there were significant correlations between the primary level of slCAM-1 and primary values of BF% [P=0.031], pelvic [P=0.005] and waist [P=0.006] circumferences following endurance training, whereas changes in the levels of slCAM-1 or lipid profiles and anthropometric markers did not correlate significantly in the resistance training group [p>0.05]. Although decrease in slCAM-1 level may be associated with the beneficial effects of training on body composition or/and lipid profile, further studies are needed to elucidate the mechanisms responsible for the effects of resistance training on ICAM-1 level