The majority of citrulline benefits for health result from its capacities to increase nitric oxide (NO) synthesis and induce vasodilation.
L-citrulline is an alpha amino acid which is nonessential. It is manufactured in the body and can be gained from certain dietary sources.
People use citrulline to address medical conditions including diabetes mellitus, heart disease, erectile dysfunction, high blood pressure, vascular disease, postoperative pulmonary hypertension and dementia.
It is also used to improve immunity, reduce muscular fatigue, increase strength, boost energy levels and enhance physical performance.



- Shown to raise blood arginine levels
- Increases Nitric Oxide & Growth Hormone
- Delays onset of fatigue during intense training
Citrulline Benefits for Bodybuilding
Related Topics
- L-Citrulline
- Citrulline Malate
- L-Citrulline Supplements
- L-Citrulline Benefits
- Citrulline Malate Effects
- L-Citrulline Dosages
- Citrulline Malate Dosages
- L-Citrulline Foods
- Potential Side Effects
- Citrulline for Bodybuilding
- L-Citrulline for Depression
- Citrulline Malate Reviews
- Primaforce Citrulline Malate
- L-Arginine vs. L-Citrulline
Citrulline malate is L-citrulline combined with malic acid. Bodybuilders and other strength-training athletes use this supplement to enhance certain performance markers and support gains in lean muscle mass.
Research shows that citrulline malate is effective for increasing the production of nitric oxide. It also is helpful at increasing ATP (adenosine triphosphate) synthesis, reducing ammonia and lactic acid accumulations, and facilitating phosphocreatine recovery.
In 2015, two double-blind, randomized trials were completed by 15 trained female weightlifters. All subjects were between 20 and 26 years of age.
The effects of daily 8 g doses of citrulline malate (CM) plus 8 g of dextrose were compared to those of 8 g daily doses of dextrose alone. Dextrose was used as a placebo agent in these studies.
One hour after supplement administration, all subjects performed 6 sets of upper body exercise (bench press) and 6 sets of lower body exercise (leg press). The exercises were performed to failure at 80% of given subjects’ one-rep maximums.
Upon muscular failure in each of the twelve sets performed, rating or perceived exertion (RPE), heart rate and number of repetitions were recorded. Results included:
- Decreased RPE during upper-body exercise;
- Enhanced performance in both upper and lower body exercises;
- No significant effects on heart rate during exercise periods;
These studies concluded that acute supplementation with citrulline malate can help to improve athletic performance in events which require sustained muscular endurance.
Citrulline Benefits for ED
Erectile dysfunction (ED) may be improved with routine L-citrulline administration. Citrulline benefits include natural inhibition of of PDE-5 (phosphodiesterase-5).
PDE-5 is an enzyme that degrades cGMP (cyclic guanosine monophosphate); a nucleotide which relaxes smooth muscle tissues.
Many men used pharmaceutical drugs like Cialis, Viagra and Levitra to prevent or treat certain symptoms of erectile dysfunction.
These substances work by relaxing the smooth muscle cells which line the corpus cavernosum of the penis. Corpus cavernosum are the shafts inside the body of the penis which flood with blood to produce erections.
L-citrulline works in a similar way to these drugs, though the effects will not be as significant as with the prescription medications.
In one single-blind study involving 24 men with mild ED, L-citrulline administration was tested for its effects on erection hardness. Mild ED is marked in part by erection hardness score of 3.
All subjects received only a placebo for one month, and then 1.5-gram daily doses of L-citrulline for the next month.
Results from the study included significant changes in erection hardness scores (from 3 to 4 (normal). Also, then mean number of intercourses per month increased.
All subjects reported being very satisfied with the citrulline benefits they experienced. They reported strong psychological benefits as well.
Short-term L-citrulline benefits for ED are not as pronounced as the benefits of PDE-5 inhibitor drugs like Viagra. L-citrulline may provide a safer approach to managing and preventing erectile dysfunction symptoms, especially for long-term usage scenarios.
Natural Sources of Citrulline
The term “citrulline” comes from the botanical name for the watermelon plant: Citrullus vulgaris. It is also known by the scientific name, 2-amino-5-(carbamoylamino)pentanoic acid.
Watermelon is the most concentrated food source of L-citrulline. However, even multiple daily servings of watermelon do not significantly increase serum L-citrulline levels.
For those who want to experience the health benefits of L-citrulline, dietary supplementation may be required.
Safe Dosages of L-Citrulline
There are no adverse effects associated with using citrulline supplements. In healthy adults, 0.13 g/kg/day doses have been used without causing side effects for as long as 9 months. 15-gram single doses have also been used without ill effects.
Infants have had 0.17 g/kg/day doses delivered safely. There is a single case report of a 2-year old who received 5.7-gram daily intravenous doses over 20 months. No side effects were reported.
There is not enough data pertaining to citrulline benefits and side effects for pregnant or nursing women. Usage is not recommended for those groups.
Conclusions
Citrulline benefits for athletic performance, erectile dysfunction, heart disease and certain other conditions and diseases continue to be researched.
Usage is well tolerated in most healthy individuals and no adverse effects have been reported. L-citrulline may interact negatively with drugs and herbs that cause blood pressure levels to drop.
- Glenn JM1,2,3, Gray M4,5, Wethington LN4, Stone MS4,5, Stewart RW Jr4,5, Moyen NE5. Acute citrulline malate supplementation improves upper- and lower-body submaximal weightlifting exercise performance in resistance-trained females. Eur J Nutr. 2015 Dec 11. [Epub ahead of print]
- Cormio L1, De Siati M, Lorusso F, Selvaggio O, Mirabella L, Sanguedolce F, Carrieri G. Oral L-citrulline supplementation improves erection hardness in men with mild erectile dysfunction. Urology. 2011 Jan;77(1):119-22. doi: 10.1016/j.urology.2010.08.028.
- Pérez-Guisado J1, Jakeman PM. Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res. 2010 May;24(5):1215-22. doi: 10.1519/JSC.0b013e3181cb28e0.
- Figueroa A1, Trivino JA, Sanchez-Gonzalez MA, Vicil F Oral L-citrulline supplementation attenuates blood pressure response to cold pressor test in young men. Am J Hypertens. 2010 Jan;23(1):12-6. doi: 10.1038/ajh.2009.195. Epub 2009 Oct 22.
- Ochiai M1, Hayashi T, Morita M, Ina K, Maeda M, Watanabe F, Morishita K. Short-term effects of L-citrulline supplementation on arterial stiffness in middle-aged men. Int J Cardiol. 2012 Mar 8;155(2):257-61. doi: 10.1016/j.ijcard.2010.10.004. Epub 2010 Nov 9.
- Orozco-Gutiérrez JJ1, Castillo-Martínez L, Orea-Tejeda A, Vázquez-Díaz O, Valdespino-Trejo A, Narváez-David R,Keirns-Davis C, Carrasco-Ortiz O, Navarro-Navarro A, Sánchez-Santillán R. Effect of L-arginine or L-citrulline oral supplementation on blood pressure and right ventricular function in heart failure patients with preserved ejection fraction. Cardiol J. 2010;17(6):612-8.
Article last updated on: March 12th, 2018 by Nootriment