[Effects of resistance exercise intensity on adipokines and insulin resistance index]

ABSTRACT

Adipose tissue secretes multiple proteins known as adipokines that modulate various biological functions. The present study was designed to determine the effect of resistance exercise intensity on leptin, adiponectin and the insulin resistance index in young healthy men. Fifteen healthy male subjects [Mean +/- SD; age 26.2 +/- 4.1 years; weight 75 +/- 9.1 kg; height 174 +/- 7.0 cm] voluntarily participated in the study. After two familiarization sessions and determining of maximal strength, all subjects completed three resistance exercise trials at an intensity corresponding to 30%, 55%, and 80% of 1-RM randomly. The three resistance exercise protocols included the performance of 1] 3 sets of 20 repetitions at 30% of 1-RM, 2] 3 sets of 11 equated for volume and one minute rest was allowed between exercises and sets. Two blood samples were obtained before exercise and immediately after exercise and analyzed for leptin, adiponectin, plasma insulin and glucose. To determine the effect of resistance exercise intensity, data were analyzed using two-way repeated measures of ANOVA. Data analysis revealed that resistance exercise increase adiponectin [F1, 12=47.2], insulin [F1, 11=19.7], glucose [F1,13=9.6], concentrations and the insulin resistance index, while reducing the leptin concentration [F1,12=31.1] significantly. However, resistance exercise intensity had no significant effect on any of the above variables [P>0.05] except for leptin concentration [F2,24=5.5, P=0.01]. Based on the findings of the present study it could be concluded that resistance exercise induces significant changes in adipokines and insulin resistance index but when the resistance exercise volume is equal, except for changes in leptin, these changes are not related to the intensity of exercise