Taking L-arginine supplements every day for 8 weeks won’t make highly trained female handball players any better at running for 12 minutes straight.
Claim Language
Language Strength
definitive
Uses definitive language (causes, prevents, cures)
The claim uses 'does not improve', which is a definitive statement asserting a clear absence of effect, implying certainty rather than possibility or association.
Context Details
Domain
exercise_science
Population
human
Subject
L-arginine supplementation at 0.05–0.1 g/kg/day for 8 weeks
Action
does not improve
Target
aerobic capacity in highly trained female handball players, as measured by the 12-minute Cooper test
Intervention Details
Gold Standard Evidence Needed
According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.
Evidence from Studies
Supporting (1)
L-arginine Supplementation Does Not Enhance Anaerobic Performance in Trained Female Handball Players
The study gave handball players L-arginine pills for 8 weeks and checked if they could run farther in 12 minutes — they didn’t get any better, so the supplement didn’t help their stamina.