The effects of creatine supplementation on performance during the repeated bouts of supramaximal exercise

Aim. The aim of this study was to investigate the effects of creatine supplementation on performance during the repeated bouts of supramaximal exercise. Methods. Twenty-three untrained young males participated in the study. A double blind design was used to create the creatine and placebo groups. Wingate test was performed 5 times with 90 g(.)kg(-1) body weight load with 2-min intervals. Peak power, mean power (NIP), fatigue index (FI) were calculated. Capillary blood samples for lactate analysis were taken during the initial rest period and soon after the fifth Wingate test. For 6 days the creatine group (n=12) ingested 5 g creatine monohydrate, the placebo group (n=11) a flavored drink without creatine monohydrate 4 times daily. On the 7(th) day, the Wingate tests were repeated, as was the 1(st) day. Results. In the creatine group, NIP in the 3(rd) and 4(th) Wingate test, in the placebo group FI in the 1(st) and 2(nd) Wingate test significantly increased. While the total power output obtained from the five Wingate tests increased 7.6% from 366.3 +/- 65 W to 394 +/- 67.1 W, there was no change in the placebo group. Conclusion. It is concluded that creatine supplementation enhances total power output during the repeated bouts of supramaximal exercise separated by short resting intervals.