OnePin Peptide Library · Performance
L-Citrulline
Citrulline Malate · Citrulline
L-Citrulline is a non-essential amino acid that the body converts to L-Arginine in the kidney, bypassing intestinal arginase metabolism. This makes oral L-Citrulline more effective than L-Arginine at raising plasma arginine and supporting nitric oxide production. Citrulline Malate (1:1 or 2:1 ratio with malic acid) is the most-studied form, used widely in pre-workout supplements and clinical research.
30-60 min pre-workout.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
L-Citrulline produces higher plasma arginine than equimolar L-Arginine:
Bypassing Intestinal Arginase
Oral L-Citrulline is absorbed intact (no intestinal metabolism) and converted to L-Arginine in the kidney via the urea cycle. Plasma arginine rises ~50% higher than from equimolar L-Arginine.
Sustained NO Substrate
The renal conversion provides sustained substrate for NOS - extends NO availability vs L-Arginine's peak-and-fall pattern.
Performance Effects
Pre-workout citrulline malate (6-8g) consistently improves bench press reps, reduces soreness, and improves perceived exertion in resistance training.
Cardiovascular
Sustained NO support produces modest BP reduction (~5-10 mmHg) and improved endothelial function.
Malate Component (in Citrulline Malate)
Provides Krebs cycle intermediate - may contribute to performance benefit beyond NO mechanism.
Better Tolerability
Citrulline does not produce the GI upset common with L-Arginine - much better tolerated at therapeutic doses.
What to expect
Acute pre-workout effect within 30-60 min.
Weeks: cumulative cardiovascular benefits.
Long-term: sustained effects with continued use.
Evidence
Interactions & stacking
What's safe to combine, and what belongs in a separate pin.
Keep separate
Side effects & safety
Commonly reported
- Generally well-tolerated
- Possible mild GI at very high doses
Less common & notes
- Allergic reactions rare.
- Better tolerated than L-Arginine.
- Long-term safety good.
Pharmacokinetics
Storage. Powder/capsule. Cool dry location.
Regulatory status
Dietary supplement (US, DSHEA). Naturally found in watermelon.
Put it to work
Calculate, log & track
Open L-Citrulline straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open L-Citrulline in the app →Go deeper
The guide & community
The complete L-Citrulline walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
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