The type of training program affects appetite-regulating hormones and body weight in overweight sedentary men

Abstract

Exercise-induced weight loss can occur for several reasons, including changes in circulatory levels of appetite-regulating hormones. The purpose of this study was to compare the effect of various training programs on fasting serum levels of acylated ghrelin, peptide YY 3-36 (PYY3-36) and glucagon-like peptide-1 (GLP-1), as well as weight and body mass index (BMI) changes. Forty-four overweight men were randomly assigned into 4 groups of 11 individuals, which included (i) endurance group (3 sets of 10 min with 80%–90% of maximum heart rate), (ii) resistance group (4 sets of 8 repetitions with 80% of 1-repetition maximum), (iii) concurrent group (combination of programs of endurance and resistance groups in an alternate manner), and (iv) control group. Training protocols were conducted for 12 weeks for 3 sessions per week. Results showed that all 3 types of training programs resulted in weight loss (p = 0.000, p = 0.000, and p = 0.036 for resistance, concurrent, and endurance groups, respectively), BMI reduction (p = 0.000, p = 0.000, and p = 0.034), decreased serum acylated ghrelin (p = 0.000, p = 0.000, and p = 0.004), and increased PYY hormone levels (p = 0.028, p = 0.035, and p = 0.036). However, the effect of resistance training on these changes was more pronounced. Moreover, none of the exercise programs had any effect on serum levels of GLP-1. In addition, there was a significant positive correlation between weight (p = 0.003) and BMI (p = 0.009) changes with ghrelin while a negative correlation was observed between weight (p = 0.003) and BMI (p = 0.03) changes with PYY. The findings suggest that regular exercise training, in particular resistance training, is likely to reduce body weight and improve body composition of overweight inactive people by suppressing orexigenic hormones and stimulating the anorexigenic hormones.