The Claim
In low-caffeine-consuming female handball players aged 18–19, a single dose of 6 mg/kg of caffeine administered in the morning produces greater improvements in agility and repeated sprint performance compared to 3 mg/kg, while both 3 mg/kg and 6 mg/kg of caffeine produce similar enhancements in jump performance.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
In young female handball players who rarely consume caffeine, taking 6 mg of caffeine per kilogram of body weight in the morning improves agility and repeated sprint performance more than taking 3 mg per kilogram, but both doses improve jumping performance equally.
See the scientific wording
In low-caffeine-consuming female handball players aged 18–19, the ergogenic effect of caffeine is dose-dependent in the morning, with 6 mg/kg producing greater improvements in agility and repeated sprint performance than 3 mg/kg, while both doses similarly enhance jump performance.
Caffeine blocks natural sleep-promoting signals in the brain, which makes the brain send stronger signals to the muscles. This makes the muscles contract harder and faster during quick movements like sprinting and changing direction. A larger dose of caffeine blocks more of these signals, leading to even stronger muscle activation. For jumping, the muscles already reach their maximum force output with a smaller dose, so a larger dose doesn't make it any better.
What the research says
1 studyIn young female athletes who don’t usually drink caffeine, a bigger caffeine pill (6 mg/kg) helps them run and change direction faster in the morning than a smaller pill (3 mg/kg), but both pills help them jump about the same.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.