Caffeine

Caffeine is a stimulant found in coffee, energy drinks, tablets, and many pre-workouts. People usually use it for alertness, focus, endurance, power, and reduced perceived effort.

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Acute aid for endurance, muscular endurance, power, alertness, and perceived effort in many trained users.

Strong evidence Potential health risk strength / endurance / focus 7 linked sources Content audit 2026-05-16

Headline Finding

Umbrella review: 21 meta-analyses; benefits across tasks, stronger for aerobic performance.

Dose Context

Common research range is 3-6 mg/kg about 60 minutes pre-training; many users should start lower.

Important Caveat

Sleep disruption, anxiety, blood pressure response, and tolerance can outweigh the performance benefit.

Source Drawer

Linked Research

7 papers and evidence links - audit 2026-05-16

Position stand ISSN caffeine position stand
Review PubMed record
Meta-analysis Caffeine umbrella review
Meta-analysis Resistance power meta-analysis
Meta-analysis Endurance time-trial meta-analysis
Meta-analysis CYP1A2 genotype meta-analysis
Meta-analysis Carbohydrate/caffeine meta-analysis

Product recommendation

Evidence-Matched Product Links

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Caffeine option on Amazon
Caffeine is evidence-backed for acute performance, but dose discipline matters; check the current caffeine amount per serving before use.
Checked 2026-05-04 - Amazon
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How To Read This Rating

The score reflects evidence that the supplement does its stated job. Some jobs are direct, such as strength, endurance, or recovery; others are indirect, such as sleep, mood, appetite, or health support. A real effect can still receive a cautious practical rating when dose, safety, product quality, or audience fit remain uncertain.

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