Caffeine
A pre-workout staple. Alongside alertness and focus, it gives a small boost to strength, power and endurance. Tolerance builds with habitual use, so timing matters.
An ingredient with growing research
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Effects reported in research
Small gains in maximal strength and power
Improved endurance performance
Greater alertness and lower perceived exertion
Dosage & timing
- 3–6 mg/kg body weight, 30–60 min before training.
- Avoid late in the day to protect sleep.
Cautions
- •Excess causes palpitations, insomnia and anxiety.
- •Consult a doctor if pregnant or with heart conditions.
- •Watch total intake when combining with energy drinks.
Supporting research
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Beetroot (Dietary Nitrate)
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Citrulline
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