Dawson, B., Vladich, T., & Blanksby, B. A. (2002). Effects of four weeks of creatine supplementation in junior swimmers on freestyle sprint and swim bench performance. Journal of Strength and Conditioning Research, 16, 485-490.

This study determined whether four weeks of oral creatine supplementation could enhance single freestyle sprint and swim bench performance in experienced competitive junior swimmers (M = 10; F = 10). Ss participated in a 27-day supplementation period and pre- and post-testing sessions. In session 1 (pre-supplementation testing), Ss swam one 50-m freestyle and then (after approximately five minutes of active recovery) one 100-m freestyle at maximum speed. Blood lactate was measured before and one minute after each swim trial. Forty-eight hours later, height, mass, and the sum of six skinfolds were recorded, and a Biokinetic Swim Bench total work output test (2 x 30-second trials, with a 10-minute passive recovery in between) was undertaken. After the pretests were completed, Ss were divided into two groups of 10 by means of matched pairs on the basis of gender and 50-m swim times. A creatine-loading phase of 20 g/d for five days was then instituted, followed by a maintenance phase of 5 g/d for 22 days. Post-supplementation testing replicated the pre-supplementation tests.

Four weeks of creatine supplementation did not influence single sprint swimming performance or body mass and composition. However, 30-second swim bench total work scores for trial 1 and trial 2 increased after creatine but not placebo ingestion. Post-exercise blood lactate values were not different after supplementation for the 50- and 100-m sprint trials either within or between groups.

Implication. Four weeks of creatine supplementation did not significantly improve single sprint performance in competitive junior swimmers, but did enhance swim bench test performance.

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