Research summary · Sport psychology
Belief in caffeine and sport performance
Seventeen studies tested deceptive placebo administration in which healthy adults were told that an inactive treatment contained caffeine. Outcomes included cycling, repeated sprint and resistance-exercise performance.
- Publication year
- 2026
- First published online
- Publication type
- Systematic review and meta-analysis
- Journal
- Journal of the International Society of Sports Nutrition
- Population / context
- Healthy adults · Multiple sports and performance tasks
What the publication reports
The pooled estimate favoured placebo caffeine over baseline by a small-to-moderate standardized effect of 0.49 (95% CI 0.28–0.69). Effects varied, and meta-regression signals suggested that blinding and the proportion of male participants may influence estimates.
Limits and interpretation
Nine studies were at high risk of bias and eight had unclear risk; overall evidence certainty was low. Comparisons with baseline, heterogeneous tasks and predominantly male samples limit causal interpretation and generalisation. The result does not show that expectation replaces evidence-based preparation or that caffeine itself was effective.
Read the source
Consult the original record for the full author list, methods, references, funding and competing-interest disclosures.
Placebo effects of caffeine on sport performance: a systematic review and meta-analysis
Original publication / indexed recordPMID: 42897966DOI: 10.1080/15502783.2026.2747142Full text at the sourceReader discussion
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