Performance

Caffeine

Also known as: 1,3,7-Trimethylxanthine, Coffee extract, PURENERGY, caffeine co-crystal

Evidence

Most widely used performance enhancer. Improves endurance, strength, and cognitive function through adenosine antagonism.

Primary uses

Energy
Endurance
Focus
Strength
Thermogenesis
Fat oxidation
Appetite suppression

How it works

Blocks adenosine receptors
Increases catecholamines
Enhances fat oxidation
Central nervous system stimulant

Dosage

Typical range: 100-400 mg daily; 3-6mg/kg for performance
Timing: 30-60 min before exercise
With food: Optional
Duration: Tolerance develops; cycle
Special populations: Athletes, shift workers

Forms

Capsules/tablets
Powder
Coffee
Anhydrous
Natural (guarana, green tea)

Safety

Common side effects

Anxiety
Insomnia
Jitters
Dependency

Contraindications

Arrhythmias
Severe anxiety

Known interactions

Evidence notes

Proven ergogenic aid

Grade A: Multiple well-designed human trials support the main claims.

Related in Performance

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Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider.