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Does L-Citrulline Impact Muscle Protein Synthesis?
Madhura Mohan
L-Citrulline Malate is making waves in sports nutrition as a potential game changer. Today’s question: does L-Citrulline actually impact muscle protein synthesis?
What is L-Citrulline?
L-Citrulline is a non-essential amino acid first identified in watermelon (Citrullus vulgaris). The body can produce it, and it is also found in cucumbers, melons, and pumpkin. L-Citrulline Malate is citrulline bound to malic acid — a Krebs cycle substrate that boosts cellular ATP energy production.
Which Is Better: L-Citrulline or L-Arginine?
L-Citrulline is superior in absorbability, taste, solubility, and effectiveness. When you consume L-Arginine, it passes through the liver where it is metabolised by arginase. L-Citrulline bypasses the liver to reach the kidneys, where it converts to arginine — producing significantly higher plasma arginine (and thus nitric oxide) levels. L-Citrulline is tasteless and non-hygroscopic; L-Arginine is bitter and highly water-absorbent.
L-Citrulline Enhances Muscle Power Output
L-Citrulline enhances muscle power output by lowering the ATP cost of muscle contractions. It improves muscle function and capacity for heavy workouts through increased nitric oxide production — which improves blood circulation and oxygen/nutrient delivery to muscles. Better oxygen availability enables higher exercise intensities. More reps mean more muscle adaptation, which translates to greater gains in size and strength.
L-Citrulline Increases Time to Fatigue
Blood lactate accumulation and ammonia are primary fatigue contributors during intense exercise. By increasing arginine levels, L-Citrulline plays a key role in increasing muscle phosphocreatine stores — improving the muscle’s ability to resynthesize ATP from ADP. This meets increased muscle energy demands and directly extends time to fatigue.
L-Citrulline Promotes Muscle Protein Synthesis
Muscle protein synthesis has a very high ATP requirement. L-Citrulline upregulates energy metabolism by increasing phosphocreatine regeneration after exercise — maintaining the ATP availability required for active protein synthesis. It also converts to arginine, a precursor for nitric oxide, supporting nutrient delivery during the recovery and synthesis process. Studies show L-Citrulline Malate increases muscle protein synthesis in subjects with low protein intake.
L-Citrulline Promotes Ammonia Clearance
Ammonia is a toxic byproduct of protein metabolism that accumulates during intense exercise, causing fatigue and inhibiting glycogen formation. L-Citrulline participates in the urea cycle, helping convert ammonia to urea for safe excretion by the kidneys. By promoting ammonia clearance, citrulline helps maintain muscle function and delay the onset of fatigue.
ATOM L-Citrulline Malate
ATOM L-Citrulline Malate is a dope-free, stimulant-free, gluten-free, non-GMO, flavourful supplement containing citrulline and malic acid in a 2:1 ratio. Manufactured in a GMP-certified facility and third-party lab-tested for purity and potency. Taking ATOM L-Citrulline before a workout can upgrade your performance, increase muscle power output, extend time to exhaustion, and promote stronger muscle pumps.
Frequently Asked Questions
“L-Citrulline Malate upgrades your performance, increases muscle power output, increases time to exhaustion, and promotes stronger muscle pumps. A few extra reps over time can make an enormous difference in adding muscle mass.”
Stimulant-free, dope-free, 2:1 citrulline-to-malate ratio. 30–60 min pre-workout. Aim for higher reps — and let the compounding effect do its work.