The Claim

Caffeine mouth rinsing at a dose of 3 mg/kg produces the same improvement in volleyball-specific technical skills—including spike and serve accuracy—in adolescent male players as oral caffeine capsule ingestion, regardless of time of day, and this effect is attributable to orosensory stimulation without systemic absorption.

Source: Differential Time-of-Day Effects of Caffeine Capsule and Mouth Rinse on Physical Performance and Volleyball-Specific Skills in Adolescent Male Volleyball Players

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
70score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

Rinsing the mouth with a caffeine solution at 3 mg/kg improves volleyball spike and serve accuracy in adolescent male players just as much as swallowing a caffeine capsule, and this improvement occurs without caffeine entering the bloodstream.

See the scientific wording

Caffeine mouth rinsing at 3 mg/kg is as effective as capsule ingestion for improving volleyball-specific technical skills—such as spike and serve accuracy—in adolescent male players across all times of day, indicating that orosensory stimulation alone may enhance psychomotor precision without systemic absorption.

Why this might work

Caffeine in the mouth activates taste receptors that send signals to the brain, making the person more alert and focused. This boosts the brain's ability to control precise movements like spiking and serving a volleyball, without needing caffeine to enter the bloodstream.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Differential Time-of-Day Effects of Caffeine Capsule and Mouth Rinse on Physical Performance and Volleyball-Specific Skills in Adolescent Male Volleyball Players

    Rinsing your mouth with a caffeine solution worked just as well as swallowing a caffeine pill to help young male volleyball players spike and serve more accurately, no matter the time of day. This suggests the caffeine might be working through taste buds in the mouth, not by entering the bloodstream.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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