Effects of resistance versus endurance training on serum adiponectin and insulin resistance index

Purpose: The purpose of the present study was to investigate the effects of resistance and endurance training on serum adiponectin and insulin resistance index (S-I) in healthy men. Methods: Twenty-four healthy males (age, 35-48 years) participated in the study. The subjects were randomly assigned to one of three groups: endurance training group (n = 8), resistance training group (n = 8) and control group (n = 8). Blood samples were taken in fasting state from all subjects. The experimental groups performed either endurance or resistance training 3 days a week for 1.2 weeks. The endurance training programme included continuous running at an intensity corresponding to 75-85% of maximal heart rate, while resistance training consisted of four sets of circuit weight training for 11 stations and at an intensity corresponding to 50-60% of one-repetition maximum. The maximum numbers of repetitions in each station was 12. Results: There were significant negative correlations between serum adiponectin and body fat percentage, waist-to-hip ratio, body mass index and the insulin resistance index at baseline, whereas changes in response to training were not significantly correlated. Both endurance and resistance training resulted in a significant decrease in the S, in comparison with the control group. However, serum adiponectin did not change significantly in response to resistance and endurance training. Conclusion: Endurance and resistance training caused an improvement in insulin resistance in healthy men, but this improvement was not accompanied by increased adiponectin levels.