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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.
22 of 36 results reported a benefit, from 8 published studies.
8 studies, including a review of trials
The main strength evidence is an 8-study meta-analysis, mostly of citrulline malate, which found a few more repetitions before failure; single trials disagree. The calf-strength gain comes from one 16-person trial. Pure L-citrulline and citrulline malate are different forms.
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 resultMuscular force production. Influenced by training, protein intake, hormones, and neuromuscular efficiency.
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 strength.
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 strength. 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 31714265 2020 | Systematic review | 250 participants | - | muscle mass | reported qualitatively | Benefit |
| PMID 31714265 2020 | Systematic review | 250 participants | - | muscle strength | reported qualitatively | Benefit |
| PMID 31714265 2020 | Systematic review | 250 participants | - | physical performance | reported qualitatively | Benefit |
| PMID 31714265 2020 | Systematic review | 250 participants | - | upper muscle strength | reported qualitatively | Benefit |
| PMID 31714265 2020 | Systematic review | 250 participants | - | walking speed | reported qualitatively | Benefit |
| PMID 34010809 2021 | Meta-analysis | 137 | - | Total number of repetitions performed before reaching voluntary muscular failure | 3 ± 5 (p = .022) | Benefit |
| PMID 40470618 2025 | Randomised trial | Thirty-three | 6-week | 1-repetition maximum strength (hack squat, bench press), either form | reported qualitatively | No benefit |
| PMID 40470618 2025 | Randomised trial | Thirty-three | 6-week | Lower-body repetitions to failure, L-citrulline vs placebo (trend) | reported qualitatively (p = 0.070) | Unclear |
| PMID 40470618 2025 | Randomised trial | Thirty-three | 6-week | Muscular endurance and nitric-oxide response, L-citrulline vs citrulline malate | reported qualitatively | No benefit |
| PMID 40470618 2025 | Randomised trial | Thirty-three | 6-week | Upper-body repetitions to failure (bench + incline press), citrulline malate vs placebo | reported qualitatively (p = 0.026) | Benefit |
| PMID 40470618 2025 | Randomised trial | Thirty-three | 6-week | Upper-body repetitions to failure (bench + incline press), L-citrulline vs placebo | reported qualitatively (p < 0.001) | Benefit |
| PMID 40944179 2025 | Randomised trial | 16 | 4 weeks | Calf muscle strength | ∆1.5 ± 2.8 vs. ∆-0.3 ± 1.2 kg (p < 0.05) | Benefit |
| PMID 40944179 2025 | Randomised trial | 16 | 4 weeks | Calf muscle strength relative to body weight | ∆0.02 ± 0.03 vs. ∆-0.01 ± 0.02 kg/kg (p < 0.01) | Benefit |
| PMID 40944179 2025 | Randomised trial | 16 | 4 weeks | Endothelial function (reactive hyperaemia index, log) | ∆0.11 ± 0.16 vs. ∆-0.08 ± 0.24 (p < 0.05) | Benefit |
| PMID 40944179 2025 | Randomised trial | 16 | 4 weeks | Forearm muscle oxygenation over 2 minutes (TOI area under curve) | ∆154 ± 187 vs. ∆-41 ± 194%/s (p < 0.01) | Benefit |
| PMID 40944179 2025 | Randomised trial | 16 | 4 weeks | Forearm muscle oxygenation range (TOI) | ∆2.6 ± 3.3 vs. ∆-1.5 ± 4.8% (p < 0.01) | Benefit |
| PMID 40944179 2025 | Randomised trial | 16 | 4 weeks | Forearm muscle oxygenation response (TOI hyperaemic response) | ∆1.2 ± 1.4 vs. ∆-0.6 ± 2.8% (p < 0.05) | Benefit |
| PMID 40944179 2025 | Randomised trial | 16 | 4 weeks | Plasma arginine | ∆43 ± 28 vs. ∆1 ± 16μM/L (p < 0.001) | Benefit |
| PMID 29210953 2018 | Randomised trial | 12 | - | Repetitions and power output on the other sets | reported qualitatively | No benefit |
| PMID 29210953 2018 | Randomised trial | 12 | - | Repetitions performed on set 3 | reported qualitatively (P = 0.015) | Harm / risk |
| PMID 29210953 2018 | Randomised trial | 12 | - | Repetitions performed on set 4 | reported qualitatively (P = 0.089) | Unclear |
| PMID 26658899 2017 | Randomised trial | Fifteen | - | Heart rate during exercise | reported qualitatively | No benefit |
| PMID 26658899 2017 | Randomised trial | Fifteen | - | Lower-body repetitions to failure (leg press), citrulline malate vs placebo | 66.7 ± 30.5 vs. 55.13 ± 20.64 (p = .03) | Benefit |
| PMID 26658899 2017 | Randomised trial | Fifteen | - | Perceived exertion during upper-body exercise, citrulline malate vs placebo | 7.9 ± 0.3 and 8.6 ± 0.2 (p = .02) | Benefit |
| PMID 26658899 2017 | Randomised trial | Fifteen | - | Upper-body repetitions to failure (bench press), citrulline malate vs placebo | 34.1 ± 5.7 vs. 32.9 ± 6.0 (p = .045) | Benefit |
| PMID 29057836 2017 | Randomised trial | Nine | - | Creatine kinase (muscle damage marker) after resistance exercise | reported qualitatively | No benefit |
| PMID 29057836 2017 | Randomised trial | Nine | - | Maximum repetitions during 72-hour recovery after resistance exercise | reported qualitatively | No benefit |
| PMID 29057836 2017 | Randomised trial | Nine | - | Muscle soreness after resistance exercise | reported qualitatively | No benefit |
| PMID 29057836 2017 | Randomised trial | Nine | - | Perceived exertion during recovery tests | reported qualitatively | No benefit |
| PMID 27017895 2016 | Randomised trial | Seventeen | One hour after consumption | ability to sustain power | reported qualitatively | No benefit |
| PMID 27017895 2016 | Randomised trial | Seventeen | One hour after consumption | average grip strength | reported qualitatively (p = .045) | Benefit |
| PMID 27017895 2016 | Randomised trial | Seventeen | One hour after consumption | average vertical power | reported qualitatively (p = .51) | No benefit |
| PMID 27017895 2016 | Randomised trial | Seventeen | One hour after consumption | explosive power | reported qualitatively (p < .001) | Benefit |
| PMID 27017895 2016 | Randomised trial | Seventeen | One hour after consumption | maximal grip strength | reported qualitatively (p = .042) | Benefit |
| PMID 27017895 2016 | Randomised trial | Seventeen | One hour after consumption | peak power | reported qualitatively (p < .001) | Benefit |
| PMID 27017895 2016 | Randomised trial | Seventeen | One hour after consumption | peak vertical power | reported qualitatively (p = .51) | No benefit |