The Claim
A single dose of L-arginine and citrulline malate has no measurable effect on cardiovascular recovery or endurance capacity during the Harvard Step Test in trained men.
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 one dose of L-arginine and citrulline malate does not change how quickly the heart recovers or how long endurance lasts during the Harvard Step Test in trained men.
See the scientific wording
A single dose of L-arginine and citrulline malate does not improve cardiovascular recovery or endurance capacity during the Harvard Step Test in trained men, indicating no measurable effect on aerobic fitness or heart rate recovery.
When L-arginine and citrulline malate are taken together, the body converts citrulline into arginine, which is then used to make nitric oxide. Nitric oxide relaxes blood vessels, increasing blood flow to muscles. This should improve oxygen delivery and reduce fatigue during exercise, but in trained men performing the Harvard Step Test, this process does not lead to faster heart rate recovery or better endurance.
What the research says
1 studyThe study gave trained men a single dose of L-arginine and citrulline malate before they did a step test, and found it didn’t help them recover faster or perform better — just like the claim says.
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.