Caffeine

The most effective legal performance aid there is — powerful, and easy to overuse.

EVIDENCE

Strong

TYPICAL DOSE

3–6 mg per kg of bodyweight, taken 30–60 minutes before training

TIMING

Pre-session. Avoid it within about 8 hours of bed — it wrecks sleep quality even when you fall asleep fine, and sleep is where you actually recover.

WHAT IT IS

A stimulant that reduces perceived effort and sharpens focus, letting you train or compete a little harder for the same felt cost.

WHY (OR WHY NOT)

Well-established improvements in endurance, power output and alertness. Tolerance builds, so it works best used deliberately before hard sessions rather than sipped all day.

CAUTIONS

!Anxiety, jitters, racing heart and disrupted sleep are the common downsides — find your dose, don't chase it.
!Interacts with some medications and isn't for everyone; skip it if you have a heart condition without a doctor's okay.

Note:General information, not medical advice. Supplements interact with medications and conditions — check with your doctor before starting anything, especially if you're pregnant, nursing or managing a health condition.

Caffeine

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