Caffeine is the world's most widely consumed psychoactive substance and one of the most well-researched ergogenic aids in sports science. Here's how to use it optimally.
How Caffeine Works
Caffeine blocks adenosine receptors in the brain. Adenosine accumulates throughout the day and makes you feel sleepy. By blocking these receptors, caffeine increases alertness, reduces perceived effort during exercise, and delays fatigue.
Performance Benefits
- **Endurance**: 2-4% improvement in time trial performance
- **Strength**: 3-5% increase in maximal strength
- **Power**: 3-7% increase in peak power output
- **Focus**: Improved reaction time and decision-making
- **Fat oxidation**: Modest increase in fat burning during exercise
Optimal Dosing
Performance dose: 3-6mg per kg bodyweight
- 70kg person: 210-420mg (roughly 2-4 cups of coffee)
Timing: 30-60 minutes before exercise for peak blood levels
Important: More is NOT better. Above 6mg/kg, side effects increase (anxiety, jitteriness, GI distress) without additional performance benefit. Above 9mg/kg can cause dangerous side effects.
Tolerance and Cycling
Regular caffeine users develop tolerance, reducing the ergogenic effect. Two strategies:
Option 1: Caffeine cycling — Use caffeine strategically (only pre-workout, 3-4 times per week) and take a full 7-14 day washout period every 8-12 weeks.
Option 2: Strategic abstinence — Reduce or eliminate caffeine for 7-10 days before important competitions or training blocks, then use your full dose for maximum effect.
Sleep Protection
Caffeine has a half-life of 5-6 hours. A 200mg dose at 2 PM still leaves 100mg in your system at 7-8 PM. Rule: No caffeine within 8-10 hours of bedtime. Poor sleep negates any performance benefit caffeine provides.
Best Sources
- Coffee: 80-100mg per cup (most antioxidants)
- Caffeine pills: precise dosing, cheapest per mg
- Pre-workout supplements: variable dosing, often combined with other ingredients
- Green tea: 30-50mg per cup (plus L-theanine for calm focus)