Overload Creatine Supplementation Effect On Volleyball Players Strength

Abstract

PURPOSE: To determine the effects of overload oral creatine supplementation during 7 days, on strength gain and delayed muscle fatigue of Volleyball players. METHODS: Twenty four male Volleyball players, with an average age of 21.4 yrs (±2.4) took part in this study: 12 constituted the placebo group (PG) and ingested 20 g of manitol per day, and the others ingested 20 g of creatine monohydrate (CG) per day, distributed by four doses of 5 g each (in the morning, after lunch and before and immediately after the training). To measure strength levels, all the athletes performed a Squat Jump (SJ) and a Counter Movement Jump (CMJ) in the Ergo Jump (Globus Ergo Tester) at the beginning and in the end of the training session, both before the supplementation program started (pretest) and after 7 days (posttest). The groups' strength levels comparisons between pretest and posttest and between the beginning and the end of each training session were made using two-way ANOVA with repeated measures. RESULTS: There were no differences in SJ performance between pretest and posttest either in PG (0.64 + 0.04 vs. 0.66 + 0.07 at beginning, and 0.64 + 0.05 vs. 0.65 + 0.04 at the end of training session) or in CG (0.60 + 0.07 vs. 0.59 + 0.09 at beginning, and 0.59 + 0.07 vs. 0.61 + 0.06 at the end of training session). Similarly, there were no differences in CMJ performance between pretest and posttest either in PG (0.65 + 0.04 vs. 0.67 + 0.03 at beginning, and 0.66 + 0.03 vs. 0.66 + 0.03 at the end of the training session) or in CG (0.61 + 0.07 vs. 0.60 + 0.08 at beginning, and 0.60 + 0.07 vs. 0.61 + 0.07 at the end of the training session). CONCLUSIONS: The overload creatine supplementation failed to induce an increase in strength gain and delayed muscle fatigue of Volleyball players.