Amino Acid
L-Citrulline Malate (2:1)
Also known as: Citrulline Malate, Citrulline Malate 2:1, CM2:1
A non-protein amino acid bound to malic acid (2:1 ratio) that enhances nitric oxide production and ATP regeneration in muscle tissue. Emerging evidence suggests superior bioavailability and endurance benefits compared to L-arginine.
Primary uses
- Nitric oxide and vasodilation
- Exercise endurance and fatigue reduction
- Muscle soreness (DOMS) reduction
- Blood flow and oxygen delivery
- ATP/energy recovery
How it works
- L-citrulline converts to L-arginine in kidneys, bypassing hepatic degradation for superior NO production
- Malic acid supports ATP synthesis in mitochondria (TCA cycle intermediate)
- Enhanced ammonia clearance, reducing fatigue metabolites
- Improved vascular endothelial function and blood flow
- Reduced protein degradation in muscle tissue
Dosage
- Typical range
- 6-8 grams daily (providing 4-5.3 g citrulline and 2-2.7 g malate)
- Timing
- 60-90 minutes before exercise for endurance; can divide daily dose
- With food
- Better absorbed on empty stomach; take with water or beverage
- Duration
- Benefits may appear within 7-14 days of consistent use; full effects by 2-4 weeks
- Special populations
- Generally very well-tolerated; safe for most populations including athletes; minimal contraindications
Forms
- Malic acid chelate 2:1 ratio· 70/100
Safety
Common side effects
- Gastrointestinal upset (rare at recommended doses)
- Mild nausea (more common at doses >8 g daily)
- Diarrhea (dose-dependent)
Contraindications
- None significant; well-tolerated across populations
- Theoretical caution with severe renal dysfunction (as with all amino acids)
Evidence notes
Good RCT evidence for endurance performance, fatigue reduction, and DOMS. Multiple studies show citrulline malate 2:1 improves exercise output and recovery better than placebo. Better evidence base than arginine for athletic performance.
Grade B: Some human trials support key claims; further confirmation needed.
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