Research

Hormonal

Caffeine supplementation (2-9 mg/kg) taken 1 hour prior to exercise significantly improves both endurance and anaerobic performance by stimulating the central nervous system and increasing serum catecholamines.

Take 2-9 mg of caffeine per kg of body weight about one hour before your workout or race. This is a proven way to boost both endurance and sprint performance. If you are sensitive to caffeine, start at the lower end of the dose range to avoid anxiety or sleep issues.

GoodSupportsHIGH confidence
a small quantity of caffeine (≈2 to 9 mg/kg body mass) taken at least 1-h prior to exercise or competition stimulates greater improvements in some measures of strength, and increases serum catecholamine levels and immune responses in runner and cyclist [35].
Maha Sellami et al. · Journal of the International Society of Sports Nutrition · 2018

Why this rating

Multiple studies cited show consistent improvements in performance metrics, though side effects at high doses are noted.

Source

Herbal medicine for sports: a review

Maha Sellami et al. · Journal of the International Society of Sports Nutrition · 2018

DOI 10.1186/s12970-018-0218-y

narrative_reviewCited 174×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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