The Claim
In healthy, moderately active young adults, 10-day L-citrulline supplementation at 100 mg/kg/day has no significant effect on cardiac output, oxygen uptake, blood lactate, or rating of perceived exertion during high-intensity cycling to exhaustion.
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.
Taking L-citrulline for 10 days at a dose of 100 mg per kilogram of body weight does not change cardiac output, oxygen use, blood lactate levels, or how hard a person feels they are working during intense cycling to exhaustion.
See the scientific wording
In healthy, moderately active young adults, 10-day L-citrulline supplementation at 100 mg/kg/day does not significantly alter cardiac output, oxygen uptake, blood lactate, or rating of perceived exertion during high-intensity cycling to exhaustion, suggesting no measurable physiological mechanism underlies its purported ergogenic effect in this context.
L-citrulline is absorbed and turned into L-arginine in the kidneys, which then fuels the production of nitric oxide in blood vessel walls. Nitric oxide causes blood vessels to widen, increasing blood flow and oxygen delivery to muscles during exercise. Despite this pathway being active, it does not result in measurable changes in heart output, oxygen use, lactate levels, or perceived effort during intense cycling.
What the research says
1 studyThis study gave people L-citrulline pills for 10 days and had them bike until they were exhausted. Their heart, lungs, and how tired they felt didn’t change compared to when they took fake pills — so the supplement didn’t help.
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.