The effect of oral creatine supplementation on maximal exercise performance in competitive rowers

Abstract

The effect of oral creatine (Cr) supplementation on maximal 2500m rowing ergometer performance (MREP) in trained oarspeople was examined in this study. Twenty subjects were tested on two occasions. Baseline measures of timed performance, VO 2.peak, VO2 total and HR were taken during the initial MREP exercise task. Capillary blood drawn pre‐ and post exercise was assayed for pH and [La−]. Subjects were then matched in two equal groups. One group of subjects was administered a Cr supplement while the other group received a placebo (Pl) these were taken 4 times a day for 5 days, in double blind fashion. The supplement dose was based on the result of a pilot study indicating that a dose of 60 mg·kg−1 body mass of CrH2O provided at least a 2 hour plasma Cr concentration above a threshold accepted as that required for the absorption of Cr from blood into skeletal muscle. Subjects were then re‐tested using the same experimental protocol as in the initial testing session. A significant difference in MREP between the two groups (p ≤ 0.05) was observed following supplementation. A group mean (±sd) improvement in performance time of 3.46 ± 4.00 seconds was observed in the Cr group while the Pl group was 3.19 ± 6.08 seconds slower in the second trial, however no significant within group change in performance was identified. Of the 10 matched pairs 8 had a change indicating improved performance following Cr supplementation. The change in post exercise blood pH following supplementation was significantly (p ≤ 0.05) better for the Cr group, however, there was no significant within group change. No significant change occurred in VO 2, body mass, HRmax or [La−] pre‐ and post exercise due to the ingestion of Cr supplement. It was concluded that Cr supplementation is potentially of benefit to rowing ergometer performance. Further research is required to investigate the trend towards performance improvement identified in this study.