Appetite regulating hormones and body composition responses to resistance training and detraining in men with obesity: a randomized clinical trial

Purpose The aim of this study was to determine the responses of appetite regulating hormones and body composition to different periods of resistance training (RT) and subsequent detraining in men with obesity. Methods Thirty obese males were randomly assigned into two groups of 15 individuals which included the RT group (3 sessions per week, 4 sets of 8 repetitions with 80% of 1RM) and control group. Measurements were performed in five steps and each time after 10 h overnight fasting: before the start of the training program, after the 8, 16, and 24 weeks of RT, and finally after 2 weeks detraining. Results Between groups comparisons showed plasma concentrations of acylated ghrelin and insulin hormones, as well as body weight, BMI, WHR, and body fat percentage were significantly lower in the experimental group compared to the control group after 2, 4, and 6 months of RT (in all cases, p <= 0.05). However, after 4 and 6 months of RT, the levels of peptide YY was higher in the training group in comparison to the control group (p = 0.001 and p = 0.001, respectively). Within group changes indicated acylated ghrelin reduced (mean difference, -9.27 pg/dl; P = 0.001), while PYY increased (mean difference, 2.66 pg/dl; P = 0.001) after 6 months of RT compared to the pre-test. By increasing the duration of training, changes in the variables were more perceptible. After detraining, most of the changes were reversed. Conclusion Performing RT by regulating appetite-related hormones can lead to weight loss and improvement of BMI in men with obesity.