Mixed

Acute caffeine ingestion (2.5–7 mg/kg) significantly improves performance in short-term high-intensity exercise (sprinting, team sports, resistance training), with effects being more pronounced in trained athletes and non-habitual users.

If you are a trained athlete engaging in short, high-intensity efforts (like sprinting or heavy lifting), taking 3-6 mg of caffeine per kg of body weight about 45-60 minutes before exercise can improve performance by roughly 6-9%. This benefit is strongest if you are not a heavy daily coffee drinker. If you are untrained or doing long endurance, the benefit is less clear. Avoid doses above 9 mg/kg to prevent side effects like anxiety.