Effects of two and five days of creatine loading on muscular strength and anaerobic power in trained athletes

J Strength Cond Res. 2009 May;23(3):906-14. doi: 10.1519/JSC.0b013e3181a06c59.


The purpose of this study was to establish the effects of 2 and 5 days of creatine loading, coupled with resistance training, on muscular strength and anaerobic performance in trained athletes. Seventeen trained men were randomly assigned to a creatine or a placebo group. The creatine supplementation group consumed 20 g of creatine per day (4 doses of 5 g per day), whereas the placebo group was given a placebo similar in appearance and taste over the 5-day supplementation duration. Anaerobic power and strength performance measures, in addition to blood and urine analysis, were conducted in the morning before the supplementation began and on the third and sixth day to establish the effect of 2 and 5 days of creatine loading, respectively. The study found that a 5-day creatine loading regime coupled with resistance training resulted in significant improvements in both average anaerobic power, as measured by the 30-second Wingate test and back squat strength compared with just training alone. However, 2 days of supplementation was not sufficient to produce similar performance gains as that observed at the end of 5 days of loading in trained men, despite increases in creatine uptake in the body. The standard 5-day loading regime should hence be prescribed to individuals supplementing with creatine for enhanced strength and power.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Anaerobic Threshold / drug effects*
  • Analysis of Variance
  • Anthropometry
  • Blood Chemical Analysis
  • Creatine / administration & dosage*
  • Double-Blind Method
  • Exercise Test
  • Humans
  • Male
  • Muscle Strength / drug effects*
  • Placebos
  • Resistance Training / methods*
  • Urinalysis


  • Placebos
  • Creatine