L-citrulline

Performance

ModerateSeveral human trials, smaller or less consistent.

Nitric-oxide precursor studied for training volume and the pump.

What the evidence says

Multiple small human trials show modest volume gains. Effect sizes are real but small, and study quality varies.

What studies used

6–8 g citrulline malate pre-training in trials. ~60 min before training.

Reported from published studies and product labelling — a record of what was used in research, not a recommendation. What is right for you is a conversation with a clinician.

Evidence base

A79 research papers
emerging literature

Strong human evidence: either a phase 3 or 4 trial report alongside review-level evidence, or ten or more randomised controlled trial reports.

This letter measures how much human research exists, not whether it works for you — the tier above (Moderate) is the read on quality.

Research (12)

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Where next

Every supplement in the catalogThe full shelf, grouped and evidence-tiered.→The compound indexSteroids, nootropics and research chemicals.→The peptide indexInjectable peptides and what trials used.→