Background and aims: The aim of present study was to compare the effects of 12 weeks of nonlinear resistance training (NRT) and aerobic interval training (AIT), and also effects of 4 weeks of detraining after these training on interleukin-6 (IL-6) and insulin resistance in young obese men.
Methods: In this randomized clinical trial, at first 38 obese men were matched by aerobic fitness, age and percentage of body fat. Then, they were randomly assigned to NRT (n=14), AIT (n=12) and control (Con, n=12) groups. The training groups performed 3 weekly sessions for
12 weeks followed by a 4 weeks detraining period. NRT consisted of 40-65 minutes of weight training at different intensities with flexible periodization. AIT consisted of running on a treadmill (4 sets of 4 minutes at 80-90% of maximal heart rate, with 3-minute recovery intervals). Serum levels of IL-6 and insulin resistance were measured by enzyme-linked immunosorbent assay (ELISA) and the glucose oxidase method for serum glucose concentration.
Results: Compared to Con, it was not observed in serum IL-6 levels any change significantly after the NRT (P=0.593) and AIT (P=0.623), but this cytokine worsened significantly after detraining with the NRT (P=0.011) and AIT (P=0.017). Both NRT (P=0.006) and AIT (P=0.046) groups was equally effective at reducing insulin resistance, but these values returned to the pre-training levels after detraining.
Conclusion: The young obese men can use the two exercise programs to reduce insulin resistance. Also, IL-6 increased significantly in both training groups after detraining. Thus, it is recommended that the training programs should not be discontinued to prevent worsening of inflammatory conditions
