Effects of caffeine ingestion on exercise testing: a meta-analysis.
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.
Doherty
Mike
M
Dept of Sport, Exercise and Biomedical Sciences, University of Luton, Beds LU1 3JU, UK.
Smith
Paul M
PM
D000328:Adult; D002110:Caffeine / Q000008:administration & dosage*; D016001:Confidence Intervals; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D016017:Odds Ratio; D010807:Physical Endurance / Q000502:physiology*; D016032:Randomized Controlled Trials as Topic
D002110:Caffeine