Mixed
Caffeine supplementation (3-6 mg/kg body mass) taken 60 minutes before exercise consistently improves endurance performance by approximately 3.2% and high-intensity sprint performance by approximately 6.5%.
Take 3-6 mg of caffeine per kg of body weight about an hour before your event. For a 70kg athlete, this is roughly 210-420mg. This dose is proven to improve endurance by ~3% and high-intensity efforts by ~6.5%. Do not exceed this dose, as higher amounts increase side effects like anxiety and nausea without improving performance. This works regardless of whether you are a regular coffee drinker.
caffeine supplementation achieved an average performance benefit of ~3.2% (±4.3%) when provided before and/or during endurance-based TT activities... a systematic review of caffeine ingestion and high-intensity efforts of ≤5 min duration reported that ~65% of studies resulted in performance benefits, with a mean task improvement of ~6.5% (±5.5%)
Why this rating
Supported by systematic reviews of 33 trials and multiple high-quality studies across various exercise modalities.
Source
Evidence-Based Supplements for the Enhancement of Athletic Performance
Peter Peeling et al. · International Journal of Sport Nutrition and Exercise Metabolism · 2018
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