This study investigated the effects of acute creatine (Cr) supplementation on the performance of elite female soccer players undertaking an exercise protocol simulating match play. On two occasions, 7 days apart, 12 players performed 5 X 11-min exercise testing blocks interspersed with 1 min of rest. Each block consisted of 11 all-out 20-m running sprints, 2 agility runs, and 1 precision ball-kicking drill, separated by recovery 20-m walks, jogs, and runs. After the initial testing session, subjects were assigned to either a CREATINE (5 g of Cr, 4 times per day for 6 days) or a PLACEBO group (same dosage of a glucose polymer) using a double-blind research design. Body mass (BM) increased (61.7 ± 8.9 to 62.5 ± 8.9 kg, p < .01) in the CREATINE group; however, no change was observed in the PLACEBO group (63.4 ± 2.9 kg to 63.7 ± 2.5 kg). No overall change in 20-m sprint times and agility run times were observed, although the CREATINE group achieved faster post-supplementation times in sprints 11, 13, 14, 16, 21, 23, 25, 32, and 39 (p < .05), and agility runs3,5,and8 (p < .05). The accuracy of shooting was unaffected in both groups. In conclusion, acute Cr supplementation improved performance of some repeated sprint and agility tasks simulating soccer match play, despite an increase in BM.
G. Cox and L. Burke are with the Australian Institute of Sport, Department of Sports Nutrition, Leverrier Crescent, Bruce, Australian Capital Territory, Belconnen, A.C.T. 2616, Australia. I. Mujika is with the Department of Research and Development, Medical Services, Athletic Club of Bilbao, Basque Country, Spain. D. Tumilty is with the Australian Institute of Sport, Department of Physiology, Leverrier Crescent, Bruce, Australian Capital Territory, Belconnen, A.C.T. 2616, Australia.