Plasma levels of leptin in overweight adults undergoing concurrent training

Objective: To assess the acute effects of concurrent training (CT) on plasma leptin levels in overweight adults. Material and methods: Quasi-experimental research methods were used. A sample of twenty individuals (27.7 ± 5.1 years-old, BMI 27.08±1.42) was randomly divided between the experimental group (EG: n=10) and the control group (CG: n=10). After subjects had fasted for 12 hours, blood samples were collected from both groups, and plasma leptin levels were assessed. Forty minutes after breakfast, the EG performed CT which included an indoor cycling class (40min, OMNI 57) followed by resistance training (3 series performed until exhaustion in the supported row machine, leg press, straight bench press, knee extensor, elbow flexor, knee flexor and elbow extensor, 85% 1RM, 2-3min interval). The CG did not perform the physical exercises. At the end of the CT, blood samples were collected from the EG. Descriptive statistics were used and for the inferential analysis a two-way ANOVA was undertaken. The Shapiro-Wilk test was used to check homogeneity and Tukey’s Post-Hoc test was used for normality analysis. The significance level adopted was p<0.05. Results: The EG (Δ% = 2.92; p = 0.01; 15.05±3.32ng/mL for 12.13±3.01ng/mL) and CG (Δ% = 5.32; p = 0.00; 26.04±9.13ng/mL for 20.72±8.51ng/mL) had significant reductions in plasma leptin levels. Conclusion: In its acute phase, CT causes a reduction in the plasma leptin levels of overweight individuals. Keywords: leptin, physical exercise, resistance training, aerobic training, hormones