Summary 

Citrulline Malate has been used for medicinal purposes in Europe for more than 20 years. Its original use was as an antiasthenic, for treatment of patients with fatigue and muscle weakness. [1]

Benefits and Effects 

Improves cardiovascular health

Participants consuming L-Citrulline supplements (available from Citrulline Malate) showed a consistently better blood pressure performance in the CPT than other participants. [2]

Researchers have also investigated the benefits of Citrulline Malate in heart failure patients. The right ventricle ejection fraction increased, while the systolic pulmonary artery pressure decreased. [3]

Increases aerobic energy production

Citrulline Malate increases the rate of muscle ATP while exercising. Sugar and fats are burned up in muscle cells under the influence of weak amino acids. Citrulline Malate helps this process keep going thus improving endurance. [1]

Improves protein absorption in the aged

Citrulline improves the protein metabolism leading to higher protein synthesis and muscle content. Further studies are needed to further evaluate this mechanism of action in humans, but initial signs are promising. [4]

May improve male erectile dysfunction

One study in particular reports that half of the subjects reported an improvement in their erectile hardness. Citrulline Malate may influence the action of enzymes that inhibit the flow of blood to the penis. [5]

May improve cognitive performance in athletes

A selection of Taekwondo athletes participated in three successive fights. Cognitive performance was measured using Taekwondo specific reaction tests. Those athletes taking the BCAA, Arginine and Citrulline stack produced a significantly superior cognitive performance compared to those taking a placebo. [6]

How it Works 

The ‘Malate’ of Citrulline Malate works on the Krebs cycle in the body. This cycle is primarily involved in the conversion of oxygen to energy. Malate seems to reduce the effects of excess ammonia that builds up during exercise. It also uses lactic acid to make pyruvate. Aerobic metabolism continues freely, producing more ATP and therefore reducing fatigue. [7]

Dosage 

Studies show that an optimum dose of Citrulline Malate for improved exercise performance is about 8 g per day. However, from about 3 g per day effects are already noticeable. [7]

Side Effects 

Citrulline Malate should not be taken with medication that treats high blood pressure. [8]

On the other hand, Citrulline Malate may cause a sudden drop in blood pressure when combined with drugs like Viagra and other PDE-5 inhibitors. [8]

If you are already taking medication for a heart condition, it is also advisable to check with your doctor before adding Citrulline Malate to your diet. Its pharmacological action on the heart and arteries could put you at risk. [8]

Pregnant women and nursing mothers should avoid Citrulline Malate.

Stacks 

Citrulline Malate is especially useful as part of a high-level training regime. A typical stack may look like this [9]:

• Whey protein hydrolysate
• whey protein isolate
• micellar casein
• Dextrose
• Creatine
• Glutamine
• L-carnitine
• L-tartrate
• citrulline malate
• beta-alanine
• caffeine

A BCAA, Arginine and Citrulline stack has been shown to improve cognitive and exercise performance in tournament athletes. [6]