Performance

Arginine and citrulline support nitric oxide (NO) production — wider blood vessels, more blood and oxygen to the muscles and that pump feeling; in studies citrulline has proved more effective than arginine. Beta-alanine raises muscle carnosine and delays fatigue during intense efforts lasting 1–4 minutes.

Take them on their own or add them to your own pre-workout mix — ideal if you like full control over doses.