Coffee Before a Workout: What Caffeine Studies Show

A landmark 2020 review in the British Journal of Sports Medicine analyzed 21 meta-analyses spanning thousands of trials and concluded that caffeine reliably improves muscular endurance, strength, sprint performance, and aerobic capacity at doses between 3 and 6 mg per kilogram of body weight — roughly one to two strong cups for most adults.

The effect sizes are not enormous in absolute terms — typically 2 to 7 percent — but in elite competition that margin is often the difference between the podium and a footnote.

Evidence specific to brewed coffee is smaller than the evidence for isolated caffeine. One study comparing coffee with an equivalent caffeine dose reported a difference on a sprint measure, but a single protocol does not establish that coffee generally outperforms caffeine supplements.

Brew method, bean, serving size, and preparation make a cup's caffeine dose harder to standardize than a measured capsule, which limits direct comparison.

Sports-nutrition position statements discuss timing and weight-based caffeine ranges, but brewed coffee varies substantially in caffeine content. Individual response, medications, heart conditions, anxiety, sleep, pregnancy, and sport rules all matter; this article is not a dosing recommendation.

The practical implication is to distinguish evidence about measured caffeine from claims about an unmeasured cup of coffee. Preference and convenience do not establish superior performance.