Caffeine as an Ergogenic Aid

Caffeine is a central-nervous-system stimulant and one of the most consistently effective legal ergogenic aids. It works mainly by blocking adenosine receptors, reducing perceived exertion and fatigue, and improving alertness and neuromuscular function.

Dose (ISSN 2021): ergogenic effects are consistent at 3–6 mg/kg of body mass; the minimal effective dose may be as low as ~2 mg/kg. Higher doses (≥9 mg/kg) add side effects without extra benefit and are not recommended.

Timing: most commonly ~60 minutes before exercise (depends on the source — e.g., chewing gum acts faster).

Benefits: small-to-moderate improvements across muscular endurance, strength, movement velocity, sprinting, jumping, and throwing, and a wide range of aerobic and anaerobic sport actions; aerobic endurance shows the most consistent moderate-to-large benefit. Response varies between individuals (partly genetic).

Cautions: can cause jitteriness, elevated heart rate, GI upset, anxiety, and impaired sleep if taken later in the day — so time it away from bedtime. It has a mild diuretic effect but does not cause meaningful dehydration at normal exercise doses (see hydration). It is no longer banned by WADA but is monitored. Common sources: coffee, tea, anhydrous caffeine pills, gum, and pre-workout/energy drinks.

• CNS stimulant; blocks adenosine, lowering perceived exertion.
• ISSN: ergogenic at 3–6 mg/kg; minimal effective ~2 mg/kg; ≥9 mg/kg adds side effects, not benefit.
• Take ~60 min pre-exercise (faster via gum).
• Helps strength, power, sprint, and especially aerobic endurance; response varies.
• Avoid late-day use (sleep); not meaningfully dehydrating at normal doses.

• pre-workout-nutrition — caffeine in the pre-workout plan.
• nutrient-timing — timing the dose.
• supplements-skeptical-note — caffeine as a proven supplement.
• vo2max-intervals — endurance benefit context.