About Caffeine
Caffeine is the world's most widely consumed psychoactive substance and one of the most extensively studied ergogenic aids. A 2018 umbrella review of meta-analyses confirmed significant improvements in muscular endurance, strength, anaerobic power, and aerobic endurance. Cognitive effects include improved alertness, attention, and reaction time at doses as low as 100 mg. A 2019 meta-analysis found 3–6 mg/kg significantly improved exercise performance across multiple modalities. Tolerance develops to some effects but not all. Half-life is 3–5 hours but varies significantly by CYP1A2 genotype. Withdrawal causes headache and fatigue after 12–24 hours of cessation.
What Caffeine supports
- Improves alertness, attention, and reaction time
- Proven ergogenic aid for strength and endurance
- Enhances physical and mental energy
How much Caffeine to take
Clinical studies typically use 100–400 mg of Caffeine. FDA considers 400 mg/day safe for most adults. Ergogenic studies use 3–6 mg/kg body weight. Cognitive benefits at 100–200 mg.
- Upper limit (UL)
- 400 mg
- Effective range
- 100–400 mg
Clinical evidence
Strong clinical evidence. One of the most extensively studied ergogenic aids with umbrella reviews of multiple meta-analyses
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