Outcome
    Limited

    L-Citrulline for VO2 Max Improvement

    Citrulline improves blood flow measures with inconsistent aerobic capacity effects.

    Overview

    Citrulline improves blood flow measures with inconsistent aerobic capacity effects.

    Verdict

    Insufficient evidence

    How It Works

    Raises nitric oxide availability, improving vasodilation and oxygen delivery.

    Dosing & Protocol

    Typical dose

    Recommended dose
    6-8 g citrulline malate pre-exercise or 3-6 g/day L-citrulline (studied doses)
    Expected timeframe
    Not applicable — benefit not demonstrated

    Protocol

    dose
    6-8 g pre-exercise or 3-6 g/day chronic
    form
    Citrulline malate or L-citrulline
    timing
    Pre-exercise or daily
    duration
    Not applicable — benefit not demonstrated

    Evidence

    What the studies say

    Trials show improved exercise tolerance and reduced soreness. VO2 max improvements are not consistently demonstrated.

    Effect of food sources of nitrate, polyphenols, L-arginine and L-citrulline on endurance exercise performance: a systematic review and meta-analysis of randomised controlled trials

    Score: 9/10
    2021
    meta_analysis

    d'Unienville NMA, Blake HT, Coates AM +1 more

    No effect on exercise performance following consumption of foods rich in L-citrulline was identified (SMD=-0.03, p=0.24).

    View source

    Safety

    Caveats

    INSUFFICIENT verdict — trials using these doses have not shown consistent VO2-max increases; structured aerobic training remains the proven intervention. Do not market as a VO2-max supplement. Nitrate/PDE5 interaction applies.

    Less likely to help if

    Essentially all users, based on current data

    Medical Disclaimer

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    Individual results may vary. The statements on this website have not been evaluated by the Food and Drug Administration. Products and information are not intended to diagnose, treat, cure, or prevent any disease.