Coffee beans, the most common source of caffeine

Coffee beans, the most common source of caffeine

Mike Kenneally · Unsplash

Strong evidence27 studies

Caffeine

One of the most widely studied stimulants in the world: alertness, endurance and a reduced perception of exertion during training.

EnergyEndurance

Benefits

  • Improves alertness and reduces the feeling of exertion
  • Supports endurance and performance during training
  • May slightly increase energy expenditure

Precautions

May cause nervousness, palpitations and sleep disturbances. Avoid taking it late in the day. Use with caution if you have high blood pressure, heart problems, anxiety or are pregnant.

Recommended dosage

3 to 6 mg per kg of body weight, 30 to 60 minutes before exercise

Did you know?

A habitually high intake of caffeine does not appear to negate the benefits of acute caffeine supplementation on endurance performance.

What the studies say

  • This study reveals that a genetic polymorphism (CYP1A2) can significantly influence the ergogenic effect of caffeine. Individuals who are homozygous for the A allele of this gene showed a greater improvement in performance (4.9 per cent) following supplementation with 6 mg/kg of caffeine compared with those carrying the C allele (1.8 per cent). These results suggest that genetics plays a key role in the individual response to caffeine.

    Womack CJ, Saunders MJ, Bechtel MK, Bolton DJ, Martin M, Luden ND, Dunham W, Hancock M. — (2012)View the source study

Pairs well with

For information only: not a substitute for medical advice. Dietary supplements are not a replacement for a varied, balanced diet. Learn more