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Browse medicines, supplements, herbs, and health foods. Each profile brings community reports and linked research into one clear view.
Browse medicines, supplements, herbs, and health foods. Each profile brings community reports and linked research into one clear view.
Amino acid named after watermelon (Citrullus) that the kidneys turn into arginine, so it raises blood arginine and nitric-oxide markers. Sold in two forms that are not interchangeable: pure L-citrulline, and citrulline malate, which is citrulline bound to malic acid, so a gram of it contains less citrulline. Most gym trials used citrulline malate: a meta-analysis of 8 studies found about 6% more repetitions before failure, while cycling and endurance trials were mostly negative. Blood-pressure findings are mixed: a 2018 meta-analysis found no effect, while small trials of pure L-citrulline in older, hypertensive or diabetic adults report lower aortic pressure and better artery function.
4 of 15 results reported a benefit, from 4 published studies.
4 studies, including a review of trials
These are the figures the studies reported, not a prediction for any one person. Where several studies measured the same thing in the same unit, we show a simple average and say so. Every individual result is listed below.
See every resultSustained physical performance — cardiovascular capacity, stamina, and oxygen utilisation during prolonged exercise.
Also known as: Citrulline, Citrulline malate, L-Citrulline DL-malate
Every published result for this pair, extracted and audited.
These charts group published studies by what they reported and how they were run — green marks studies that reported a benefit for this pairing. Tiers run from pooled analyses of many trials (strongest) to one-off observational reports.
Direction of reported outcomes for L-Citrulline in endurance.
Study designs behind these findings.
Hand-selected PubMed studies, linked to the originals.
Be the first to share what you noticed with L-Citrulline for endurance. Why counts start empty.
Every measured outcome, one row per finding - numbers exactly as reported.
| Study | Design | n | Duration | Outcome measured | Reported result | Direction |
|---|---|---|---|---|---|---|
| PMID 31977835 2020 | Systematic review | - | - | Acute vasodilation and muscle blood flow (scarce, inconsistent evidence) | reported qualitatively | Unclear |
| PMID 31977835 2020 | Systematic review | - | - | Exercise performance and recovery | reported qualitatively | Unclear |
| PMID 31977835 2020 | Systematic review | - | - | Plasma citrulline, arginine and nitrate/nitrite concentrations | reported qualitatively | Benefit |
| PMID 39417670 2024 | Randomised trial | - | 28 consecutive days | Oxygen uptake (VO2), citrulline-alone group, before vs after 28 days | reported qualitatively (p = 0.04) | Unclear |
| PMID 31994989 2021 | Randomised trial | 28 | - | fatigue index (FI) | reported qualitatively (p>0.05) | No benefit |
| PMID 31994989 2021 | Randomised trial | 28 | - | mean watts | reported qualitatively (p>0.05) | No benefit |
| PMID 31994989 2021 | Randomised trial | 28 | - | peak watts | reported qualitatively (p>0.05) | No benefit |
| PMID 31994989 2021 | Randomised trial | 28 | - | time-to-exhaustion [TTE] | reported qualitatively (p>0.05) | No benefit |
| PMID 31994989 2021 | Randomised trial | 28 | - | Total Work Completed (TWC) | reported qualitatively (p>0.05) | No benefit |
| PMID 26808848 2016 | Randomised trial | 10 | - | Exercise heart rate (higher with citrulline malate) | reported qualitatively | Unclear |
| PMID 26808848 2016 | Randomised trial | 10 | - | Plasma citrulline concentration increase | 8.8-fold (p ≤ 0.05) | Benefit |
| PMID 26808848 2016 | Randomised trial | 10 | - | Plasma glutamine concentration increase | 1.3-fold (p ≤ 0.05) | Benefit |
| PMID 26808848 2016 | Randomised trial | 10 | - | Plasma ornithine concentration increase | 3.9-fold (p ≤ 0.05) | Benefit |
| PMID 26808848 2016 | Randomised trial | 10 | - | Power fatigue index | 36 ± 16% CM vs. 28 ± 18% PL (p > 0.05) | No benefit |
| PMID 26808848 2016 | Randomised trial | 10 | - | Time-to-exhaustion (TTE) | 120 ± 61 seconds CM vs. 113 ± 50 seconds PL (p > 0.05) | No benefit |