Caffeine and energy drinks

Caffeine is the best-proven stimulant: it raises strength, endurance and focus.

• Effective dose: 3 mg/kg 30–60 minutes before training (~200 mg at 70 kg, about 2 cups of coffee).
• Healthy adults: no more than 400 mg a day in total; in pregnancy up to 200 mg.
• Stop 6–8 hours before sleep.
• Energy drinks are full of sugar — coffee or a pre-workout is better.

Racing heart, anxiety or headache? Lower the dose. Avoid with heart or blood-pressure problems.