Citrulline Malate (2:1)
Citrulline Malate (2:1) is a unrated form of L-Citrulline, used in 1,085 on-market products and providing 72.3% elemental l-citrulline by weight.
Basis: Provisional: 2:1 citrulline:malic acid (2 x 175.19 / 484.47); the 2:1 salt is the common commercial grade but roughly a quarter of labels that state a ratio print 1:1 (see citrulline--malate-1-1). Bare 'Citrulline Malate' rows are assumed 2:1
Why this tier: The form used in the cited exercise trials (6-8g), but no study showing an advantage for citrulline malate over free L-citrulline exists: in one randomized crossover at matched citrulline dose (5.3 g), neither form improved neuromuscular performance (Martin-Olmedo 2025). The Trexler meta-analysis itself flags the form of citrulline as an unexplored moderator.
Source: Perez-Guisado J, Jakeman PM 2010, J Strength Cond Res 24(5):1215-22, PMID 20386132; Bendahan D et al. 2002, Br J Sports Med 36(4):282-9, PMID 12145119; Trexler ET et al. 2019, PMID 30895562; Martin-Olmedo JJ et al. 2025, Int J Sport Nutr Exerc Metab 35(2):89-98, PMID 39662304