Effects of oral supplementation of creatine (Cr) on muscle strength and whole body exercise performance such as anaerobic power and/or sprint running were investigated in healthy male university students. The subjects were randomly separated into two groups (n=6 each). One group of subjects ingested 8 g of Cr monohydrate 3 times a day (24 g/day) for 12 days. The remaining subjects served as a placebo group. The Cr concentration in urine and serum and the high-energy phosphate contents in thigh muscle were measured by using an enzymatic assay and ³¹p-nuclear magnetic resonance before and after supplementation. Effects of Cr supply on isokinetic maximal force productions of knee, as well as trunk, flexion and extension at various angular velocities, maximal anaerobic power, and sprint running performance were also determined. The concentration of Cr in both serum and urine, as well as the high-energy phosphate contents in muscle, was increased by Cr loading. The maximal force production, especially in trunk muscles, and anaerobic power output during cycling exercise were improved in Cr-supplied group. No effect was induced in sprint running performance. It is suggested that the maximal force production and short-term anaerobic power may be improved by supplementation of Cr. It is also suggested that more beneficial effects may be induced if Cr supply is combined with strength training.

DESCENTE SPORTS SCIENCE Vol.20/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE