Effect of 4 Weeks of Supramaximal Sprint Interval Training on Physiological, Hormonal and Metabolic Factors

Supramaximal sprint interval training is an efficient means of improving physical fitness within a short period of time. However the effects of this type of training which cause hormonal and physiological adaptations to increase enhanced aerobic and anaerobic performances, are not well known. Thus, the purpose of the present study was to examine the effects of four weeks of supramaximal sprint interval training on some hormonal and physiological variables. Fifteen trained wrestlers were randomly assigned into two groups, the experimental (EXP=8) and controls (CON=7) groups. Before and after training, subjects performed (a) a graded exercise test and (b) four consecutive Wingate tests with 4-min recovery intervals between each. Resting blood samples were collected before and after training. Both groups followed the same wrestling training program for 4 weeks additionally, the EXP group performed a running-based anaerobic sprint test (RAST) as a supramaximal sprint interval training protocol for 4 weeks, two sessions per week. The EXP group showed improvements in VO2max (+5.4%), Peak power output (34.9%) and Mean Power Output (29.3%) after the training (P<0.05), along with significant increases in total testosterone, total testosterone/cortisol ratio (TCR) and free testosterone/cortisol (FTCR) ratio in the EXP group, but there were no significant differences between groups. Cortisol was tended to decrease in both groups (P>0.05), but none of the variables were changed in the CON group after the training. The current findings suggest that the supramaximal sprint interval training program with short recovery can increase both aerobic and anaerobic performances. The changes observed in FTCR and TCR suggest exercise training-induced anabolic adaptations.