What is Citrulline?
Citrulline is a nonessential amino acid that converts to the amino acid Arginine, the main precursor to Nitric Oxide (NO). Citrulline supplementation increases plasma Arginine levels more effectively and efficiently than Arginine supplementation; supplementing with Citrulline is superior to supplementing with Arginine.
Citrulline supports Nitric Oxide (NO) metabolism and regulation, which promotes increased blood flow to muscle aka “The Pump”.
Citrulline supplementation has been shown to reduce fatigue and muscle soreness, increase power output, and increase the number of repetitions performed on both lower body and upper body weight training exercises.
Clinically studied dosage = 2000-6000mg Citrulline per day, ideally taken pre-workout.
Citrulline vs. Citrulline Malate: What’s the Difference?
Citrulline is a very popular ingredient in pre-workout products. Pre-workouts typically contain either L-Citrulline or Citrulline Malate (L-Citrulline + DL-Malic Acid).
Malic Acid is an organic acid involved in various metabolic processes. With importance to exercise, Malic Acid plays a role in generating ATP/energy production and has anti-fatigue effects.
Commercially available Citrulline Malate is simply L-Citrulline BLENDED with DL-Malic Acid; it is NOT L-Citrulline molecularly bonded to DL-Malic Acid. Does this matter? Not really. When molecularly bonded Citrulline Malate is added to water, the bonds are broken, and you have L-Citrulline and DL-Malic Acid. Whether you start with molecularly bonded Citrulline Malate or blended L-Citrulline with DL-Malic Acid, when you ingest your pre-workout, you are getting L-Citrulline + DL-Malic Acid.
What matters most is the total dosage of L-Citrulline. Citrulline Malate is available in a 1:1 or 2:1 ratio of Citrulline to Malic Acid.
8000mg Citrulline Malate 1:1 = 4000mg L-Citrulline + 4000mg DL-Malic Acid
8000mg Citrulline Malate 2:1 = 5333mg L-Citrulline + 2666mg DL-Malic Acid
The pre-workout formula should list whether the Citrulline Malate is the 1:1 or 2:1 ratio. If a ratio is not listed, assume it is the 1:1 ratio.
While Malic Acid supplementation does have benefits to exercise performance, the total L-Citrulline dosage of 2000-6000mg is most important.
What Kind of Citrulline does MATERIA Pre-Workout Contain?
The original MATERIA formula contained 8000mg of Citrulline Malate 2:1 per serving, supplying 5333mg L-Citrulline + 2666mg DL-Malic Acid. This was a generic Citrulline Malate from China.
The new MATERIA V2.0 upgraded to a premium, higher-quality Citrulline made in the USA by Kyowa. Kyowa’s L-Citrulline is a pure, crystallized Citrulline produced through fermentation (no animal products or genetically modified materials). Kyowa’s Citrulline is truly the highest quality L-Citrulline in the world.
In addition to switching to a higher quality source, we increased to total L-Citrulline dosage from 5333mg to 6000mg per serving.
MATERIA V2.0 also contains 3000mg Malic Acid per serving. The formula still supplies L-Citrulline and DL-Malic Acid in the 2:1 ratio. Since we don’t make any product claims about Malic Acid, this ingredient is listed under “other ingredients” and not in the supplement facts.
Perez-Guisado, J. and P.M. Jakeman, Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res, 2010. 24(5): p. 1215-22.
Wax, B., et al., Effects of supplemental citrulline malate ingestion during repeated bouts of lower-body exercise in advanced weightlifters. J Strength Cond Res, 2015. 29(3): p. 786-92.
Glenn, J.M., et al., Acute citrulline malate supplementation improves upper- and lower-body submaximal weightlifting exercise performance in resistance-trained females. Eur J Nutr, 2015.
Schwedhelm, E., et al. Pharmacokinetic and pharmacodynamic properties of oral L citrulline and L arginine: Impact on nitric oxide metabolism. British Journal of Clinical Pharmacology, 65: 51-59 (2008).
Suzuki, T., et al. Oral L-citrulline supplementation enhances cycling time trial performance in healthy trained men: Double-blind randomized placebo-controlled 2-way crossover study. J Int Soc Sports Nutr, 13, 6 (2016).