Effects of oral creatine-pyruvate supplementation in cycling performance

A double-blind study was performed to evaluate the effects of oral creatine-pyruvate administration on exercise performance in well-trained cyclists. Endurance and intermittent sprint performance were evaluated before (pretest) and after (posttest) one week of creatine-pyruvate intake (Cr-pyr 2 x 3.5 g x d(-1), n = 7) or placebo (PL, n = 7). Subjects first performed a 1-hour time trial during which the workload could be adjusted at 5-min intervals. Immediately they did five 10-sec sprints interspersed by 2-min rest intervals. Tests were performed on an individual race bicycle that was mounted on an ergometer. Steady-state power production on average was about 235-245 W, which corresponded to blood lactate concentrations of 4-5 mmol x l(-1) and heart rate in the range of 160-170 beats x min(-1). Power outputs as well as blood lactate levels and heart rates were similar between Cr-pyr and PL at all times. Total work performed during the 1-h trial was 872 +/- 44 KJ in PL versus 891 +/- 51 KJ in CRpyr. During the intermittent sprint test power peaked at about 800-1000 watt within 2-3 sec, decreasing by 15-20% towards the end of each sprint. Peak and mean power outputs were similar between groups at all times. Peak lactate concentrations after the final sprint were similar to11 mmol x l(-1) in both groups during both the pretest and the posttest. It is concluded that one week of creatine-pyruvate supplementation at a rate of 7 g x d(-1) does not beneficially impact on either endurance capacity or intermittent sprint performance in cyclists.