When athletes consume 4 to 6 milligrams of caffeine per kilogram of body weight, their endurance time-trial finish times are 2.18% faster on average compared to when they do not.
See the scientific wording
Caffeine doses of 4–6 mg/kg improve endurance time-trial performance by an average of 2.18% faster finish times.
Very strong evidence
Randomized trials4 good-quality studies support this claim.
What the research says
4 studies reviewedSupporting (4)
Systematic Review With Meta-AnalysisMeta-analysis2024
When cyclists drank a moderate amount of caffeine (about 4–6 mg per kg of body weight), they finished their races about 3.2% faster on average — which means the claim that caffeine helps athletes go faster is correct.
Systematic Review With Meta-AnalysisMeta-analysis2026
When athletes take 4 to 6 mg of caffeine per kg of body weight, they finish endurance races about 2.18% faster on average — and this study found exactly that, based on many well-run experiments.
Systematic Review With Meta-AnalysisMeta-analysis2025
The study found that taking caffeine in the 4–6 mg per kg range makes athletes faster in endurance races, just like the claim says — though the best dose was actually a little lower at 3 mg/kg. Still, the higher dose worked too.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
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Score breakdown, mechanism chain, raw evidence, ideal studies needed & 4 supporting studies
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