Caffeine
The world's most widely consumed stimulant. Improves aerobic performance, strength, focus, and alertness.
What the science says
- Improved physical performance Strong evidence
An umbrella review of 21 meta-analyses confirms ergogenic effects on aerobic exercise, muscle strength, power, and anaerobic endurance.
- Increased alertness and focus Strong evidence
Reduces perceived fatigue and improves reaction time and vigilance, especially under sleep deprivation.
Dosage & safety
Studied dose3–6 mg/kg of body weight, 30–60 minutes before exercise. Avoid consumption late in the day.
SafetyHigh doses can cause insomnia, anxiety, and rapid heart rate. Individual tolerance varies widely (slow metabolizers feel more side effects). Up to 400 mg/day is generally cited as safe for healthy adults.
Scientific references
Where to buy
ALLMAX, Essentials, Caffeine, 200 mg, 100 Tablets
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Related in Physical performance
- Creatine (monohydrate) Strong evidence
- Whey Protein Strong evidence
- Beta-Alanine Moderate evidence
- BCAA (Branched-Chain Amino Acids) Limited evidence
- EAA (Essential Amino Acids) Moderate evidence
- L-Leucine Moderate evidence