Effects of Caffeine Ingestion on Exercise Testing: A Meta-Analysis

Int J Sport Nutr Exerc Metab. 2004 Dec;14(6):626-46. doi: 10.1123/ijsnem.14.6.626.

Abstract

This study used the meta-analytic approach to examine the effects of caffeine ingestion on exercise testing. Forty double-blind studies with 76 effect sizes (ES) met the inclusion criteria. The type of exercise test was classified as endurance, graded, or short-term. In comparison with placebo, caffeine improved test outcome by 12.3 % (95 % CI, 9.1 to 15.4), which was equivalent to an overall ES of 0.41 (95 % CI, 0.31 to 0.51). Endurance exercise significantly improved test outcome (P < 0.05) more than either graded or short-term exercise. When exercise protocol was examined, time-to-exhaustion (Tlim) protocols had a significantly greater (P < 0.05) ES than either the graded or the non-Tlim protocol(s). The results from this meta-analysis confirm the ergogenic effects of caffeine, particularly for endurance testing that use Tlim protocols.

Publication types

  • Meta-Analysis

MeSH terms

  • Adult
  • Caffeine / administration & dosage*
  • Confidence Intervals
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Exercise / physiology*
  • Exercise Test
  • Female
  • Humans
  • Male
  • Odds Ratio
  • Physical Endurance / physiology*
  • Randomized Controlled Trials as Topic

Substances

  • Caffeine