The Claim

In male university rowers, the combined ingestion of 200 mg caffeine and 200 mg paraxanthine is associated with a 3.3-second faster 2000-meter rowing time and an 8 W higher mean power output compared to placebo under evening training conditions.

Source: Comparative effects of caffeine and paraxanthine on rowing performance and sleep quality: a randomized crossover study

What the research says

Supports is higher

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

Supports
62score
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.

Quantitative
1 study reviewed
In plain English

Male university rowers who consumed 200 mg caffeine and 200 mg paraxanthine together rowed 2000 meters 3.3 seconds faster and produced 8 watts more average power than when they took a placebo during evening training.

See the scientific wording

In male university rowers, the combined ingestion of 200 mg caffeine and 200 mg paraxanthine is associated with a 3.3-second faster 2000-meter rowing time and a 8 W higher mean power output compared to placebo, suggesting a potential synergistic or additive ergogenic effect under evening training conditions.

Why this might work

Two compounds block signals that make the brain feel tired, which makes the brain send stronger signals to the muscles to push harder. One of these compounds also widens blood vessels in the muscles, letting more oxygen and fuel reach them during intense effort.

Supported mechanismbased on 1 study

What the research says

1 study
  1. Study: Comparative effects of caffeine and paraxanthine on rowing performance and sleep quality: a randomized crossover study

    When male rowers took both caffeine and paraxanthine together before racing, they rowed faster and pushed harder than when they took a fake pill. This suggests the two substances work better together than alone.

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

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

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