L-Citrulline Malate
Citrulline bonded to malate, taken to raise plasma arginine and nitric-oxide precursors more effectively than arginine itself. Some evidence for reduced muscle soreness and modest gains in training volume; ergogenic effects are real but smaller than the marketing implies.
01 Overview
L-citrulline is an amino acid that is converted to arginine in the kidney, raising plasma arginine and nitric oxide more reliably than oral arginine, which is largely destroyed by first-pass metabolism. The malate component is a citric-acid-cycle intermediate sometimes credited with an additional metabolic role.
Controlled trials report reduced perceived soreness and modest increases in resistance-training repetitions, plus small aerobic effects in some designs. Results are inconsistent across studies, and effect sizes are generally small, so it sits in the mid-range of the evidence hierarchy.
02 Mechanism
Raises plasma arginine and nitric-oxide availability (vasodilation, blood flow) and supplies malate as a TCA-cycle intermediate, with claimed benefits to substrate delivery and fatigue.
03 Dosing
| Tier | Dose | Route | Notes |
|---|---|---|---|
| Common | 6–8 g | Oral | Taken ~60 min pre-exercise; doses often cited as a 2:1 citrulline:malate ratio. |
04 Effects
| Effect | Magnitude | Evidence | |
|---|---|---|---|
| Reduced muscle sorenessSeveral trials report reduced perceived soreness after resistance exercise. | Lower DOMS 24-48 h post | Clinical | |
| Increased training volumeModest increases in repetitions-to-failure in some resistance-training studies; results are inconsistent. | A few extra reps | Clinical |
05 Side effects
| Effect | Severity | Frequency | Evidence | Countermeasures |
|---|---|---|---|---|
| Gastrointestinal discomfortMild stomach upset at larger doses. | Mild | Occasional | Observational | |
| Blood-pressure loweringSmall reductions in blood pressure via nitric-oxide-mediated vasodilation, relevant to those on antihypertensives. | Mild | Occasional | Observational |