Take 6–8 g of citrulline malate (2:1) about 60 minutes before training — about 3.5–4.5 g of pure L-citrulline. Meta-analyses show a small increase in reps across hard sets, but no meaningful 1RM boost. It's safe and cheap, yet clearly behind caffeine and creatine in priority.
Citrulline malate is a nitric oxide precursor used in pre-workouts. Meta-analyses find a small improvement in repetitions and high-intensity performance.
Most strength studies used 6–8 g of citrulline malate 2:1 about 60 minutes before training. Labels differ, so this converts the studied dose to your product.
What's on your label?
Dose
Take before training
6.0–8.0 g
≈ 3.4–4.6 g of actual L-citrulline, 40–60 min before your session.
Educational estimate only, not medical advice. Validate with your doctor before applying it.
Effect sizes on strength-type performance are small for all nitric oxide boosters; caffeine and creatine remain the priority.
| Supplement | Typical dose | Timing | Strength / reps effect | Evidence |
|---|---|---|---|---|
| Citrulline malate | 6–8 g | 60 min before | Small (+ a few reps) | Moderate |
| Beetroot / nitrate | 6–8 mmol (≈ 400–500 mg nitrate) | 2–3 h before | Small | Moderate |
| L-arginine | 3–6 g | Before | None to trivial | Limited |
| Caffeine (reference) | 3–6 mg/kg | 30–60 min before | Small–moderate | Strong |
| Creatine (reference) | 3–5 g daily | Any time | Moderate over weeks | Strong |
60 min before
Take it
Most studies dosed about an hour before the session.
1–2 h
Peak arginine
Plasma arginine peaks after citrulline is converted in the kidneys.
During session
Possible extra reps
Effects appear mainly on repeated sets to failure.
Daily (optional)
Chronic use
A few studies use daily intake for 1–2 weeks; less data for strength.
| Outcome | Effect | Evidence |
|---|---|---|
| Reps to failure | Small increase | Moderate |
| Max strength | No clear effect | Limited |
| Soreness | Possibly reduced | Limited |
| Muscle pump | Subjectively increased | Limited |
+ Form used in most studies.
− Only ~57% of the weight is citrulline.
+ Smaller dose for the same citrulline.
− Fewer strength studies.
+ Convenient with caffeine.
− Often underdosed (1–3 g).
+ Natural source.
− You'd need several pounds for a studied dose.
“Citrulline gives you a big strength boost.”
FalseEffects on 1RM are negligible; benefits are a few extra reps.
“Pre-workouts contain an effective dose.”
Mostly falseMany blends contain 1–3 g, well below the 6–8 g studied.
For: Hypertrophy sessions
For: Anyone curious
Pérez-Guisado & Jakeman · J Strength Cond Res · 2010
For your training: The benefit shows up across many sets, not on a single max.
Trexler et al. · Sports Medicine · 2019
For your training: Expect a small edge, not a game changer.
Vårvik et al. · Int J Sport Nutr Exerc Metab · 2021
For your training: Useful for high-volume sessions.
6–8 g of citrulline malate 2:1 about 60 minutes before training, the dose used in most studies.
Not 1RM strength meaningfully. It may add a few reps across multiple hard sets.
Citrulline. It raises blood arginine more effectively than arginine itself.
Yes, they're commonly combined in pre-workouts and there's no known negative interaction in healthy adults.
Ranked by citations. Metadata from OpenAlex (CC0).
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Timothy Daniel Allerton, David N. Proctor, Jacqueline M. Stephens et al. · Nutrients · 2018 · 231 citations · Study · Open access
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Patrick S. Harty, Megan Lynn Cottet, James K. Malloy et al. · Sports Medicine - Open · 2019 · 161 citations · Review · Open access
Citrulline Malate Enhances Athletic Anaerobic Performance and Relieves Muscle Soreness ↗
Joaquín Pérez-Guisado, Philip M. Jakeman · The Journal of Strength and Conditioning Research · 2010 · 156 citations · Study
Vårvik et al. · Int J Sport Nutr Exerc Metab · 2021 · 0 citations · Meta-analysis
Trexler et al. · Sports Medicine · 2019 · 0 citations · Meta-analysis
Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness ↗
Pérez-Guisado & Jakeman · J Strength Cond Res · 2010 · 0 citations · Study
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