Research

Hormonal

Acute ingestion of 3 mg/kg caffeine significantly improves resistance exercise performance (velocity, power, repetitions), jumping height, and sprinting power in resistance-trained men, regardless of CYP1A2 genotype (AA vs. AC/CC).

Take 3 mg of caffeine per kg of body weight about an hour before your workout. This will likely improve your speed, power, and number of reps in resistance training, jumping, and sprinting. You do not need to worry about your CYP1A2 genotype (fast vs. slow metabolizer) as this dose works for everyone. Stick to this moderate dose; you don't need extreme amounts to see benefits.

GoodSupportsHIGH confidence
Compared to placebo, caffeine ingestion enhanced: (a) movement velocity and power output across all loads... (b) the quality and quantity of performed repetitions... (c) vertical jump height... and (d) power output in the Wingate test... We did not find a significant genotype × caffeine interaction effect in any of the analyzed performance outcomes.
Jozo Grgić et al. · Journal of the International Society of Sports Nutrition · 2020

Why this rating

Randomized, double-blind, crossover design with adequate power, though small sample size (n=22).

Source

CYP1A2 genotype and acute effects of caffeine on resistance exercise, jumping, and sprinting performance

Jozo Grgić et al. · Journal of the International Society of Sports Nutrition · 2020

DOI 10.1186/s12970-020-00349-6

crossover · n=22Cited 54×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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