The effect of longer-term creatine supplementation on elite swimming performance after an acute creatine loading

J Sports Sci. 1999 Nov;17(11):853-9. doi: 10.1080/026404199365416.


We investigated the effect of an acute creatine loading (25 g per day for 4 days) and longer-term creatine supplementation (5 g of creatine or 5 g of placebo per day for 2 months) on the performance of 22 elite swimmers during maximal interval sessions. After the acute creatine loading, the mean of the average interval swim times for all swimmers (n = 22) improved (44.3+/-16.5 s before vs. 43.7+/-16.3 s after supplementation; P<0.01). Three of the 22 swimmers did not respond positively to supplementation. After 2 months of longer-term creatine supplementation or placebo, neither group showed a significant change in swimming performance (38.7+/-13.5 s before vs. 38.7+/-14.1 s after for the creatine group; 48.7+/-18.0 s before vs. 48.7+/-18.1 s after for the placebo group). We conclude that, in elite swimmers, 4 days of acute creatine loading improves swimming performance significantly when assessed by maximal interval sessions. However, longer-term supplementation for 2 months (5 g of creatine per day) did not benefit significantly the creatine group compared with the placebo group.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Adult
  • Analysis of Variance
  • Cardiotonic Agents / administration & dosage*
  • Dietary Supplements
  • Drug Administration Schedule
  • Female
  • Humans
  • Male
  • Phosphocreatine / administration & dosage*
  • Physical Endurance / drug effects*
  • Reference Values
  • Swimming / physiology*
  • Time Factors


  • Cardiotonic Agents
  • Phosphocreatine