Learn More About Citrulline Malate
1. What is Citrulline Malate?
Citrulline Malate is a combination of the non-essential amino acid Citruline, which is involved in the urea cycle and Malate, a tricarboxycylic acid cycle (TCA) intermediate. The TCA cycle is a major producer of aerobic energy within the energy powerhouses of cells, mitochondria. Citrulline Malate has shown many promising positive effects on aerobic exercise performance such as:
- Increased Aerobic Production Of Energy
- Improved Stamina And Fatigue Resistance
- Improved Recovery And Energy Levels
Citrulline, as a non-essential amino acid, is naturally produced in small quantities from the amino acid L-glutamine in the intestines. It is also found naturally in trace amounts in some foods. Citrulline is not a component of most proteins in the body; however, it is found in some specialized proteins in the hair, skin and neural cells.
Citrulline supplied by the diet is efficiently absorbed from the stomach and once it enters the bloodstream, much of it bypasses uptake in the liver and is then circulated for distribution to the kidneys, brain, muscle and other tissues for conversion to L-arginine.
According to cell biologist and researcher Elzi Volk,"Supplemental citrulline malate is a salt form of the amino acid. The malate, or malic acid, is found in fruits such as apples and enhances the effects of citrulline. Malic acid takes part in aerobic cellular respiration where oxygen and a carbon compound (acetyl Co-A) are used to produce immediate energy and CO2 in the mitochondria of the cell. This is called the Kreb’s cycle. Malate conditions the recycling of lactate and pyruvate promoting efficient energy production and protecting muscles from fatigue."
2. What does Citrulline Malate do and what scientific studies give evidence to support this?
Overall, studies suggest that citrulline malate supplementation can boost athletic performance and enhance recovery. This is possible due to the characteristics of citrulline malate. It plays a role in the elimination of amino acid breakdown products of protein metabolism and augmentation of the detoxifying capacity of liver cells in removal of ammonium and lactate from the blood.
As mentioned, Citrulline is a precursor to L-arginine. Thus, supplementation with citrulline malate has been demonstrated to increase levels of arginine and ornithine, which are both important amino acids influencing growth hormone levels and assisting in muscle growth. Nitric Oxide (NO) is synthesized from the amino acid L-Arginine. One of NO's important roles is increasing blood flow and oxygen delivery to muscles.
Because malate is believed to enhance the level of ATP (energy molecules) production through aerobic metabolism, supplemented citrulline malate is sometimes called "aerobic creatine".
Citrulline malate has been studied clinically for its potential to improve recovery from physical activity in patients with acute diseases. Further, research has demonstrated that citrulline malate has a pH balancing effect against increased blood acidity by increasing levels of bicarbonate. This may allow one to increase workout intensity for longer periods of time before the negative effects of increased acidity build up affect exercise performance.
A 1991 study by Callis, et al. demonstrated citrulline malate by oral treatment increased resistance to fatigue in rats, where the fatigue was elicited with bacterial endotoxins.
Citrulline is also involved in the urea cycle and plays a role in the detoxification of ammonia. This was demonstrated in a study showing supplementation with citrulline malate increased the rate of ammonia clearance without affecting ammonia accumulation during bicycle exercise (Vanuxem et al., 1990).
The mechanism of citrulline malate action at the muscular level is not fully known; nevertheless, in a 2002 study by Benedahan, et al., citrulline malate supplementation was shown to increase blood flow into localized regions of skeletal muscle by increasing plasma levels of arginine. It also was shown to enhance aerobic performance by providing a 34% increase aerobic energy (with a dramatic increase in the rate of ATP production during exercise) and improving phosphocreatine recovery by up to 20%. Subjects reported experiencing a significant reduction fatigue and an enhanced rate of recovery compared with aerobic performance without citrulline malate supplementation.
3. Who needs Citrulline Malate and how much should be taken? Are there any side effects or symptoms of deficiency?
Citrulline malate may be useful for all athletes for maintaining energy levels, improving recovery, enhancing exercise performance and resistance against fatigue.
Therefore, anyone who is involved in aerobic exercise (runners, swimmers, cyclists, athletes, etc.) may benefit from citrulline malate supplementation. Since citrulline malate enhances the recovery process it may be useful for bodybuilders or powerlifters as well.
Supplement manufacturers' dosages range; however, some advocate consumption of around 3000 mg of citruline malate on an empty stomach in the morning with supplementation of another 3000 mg 30-40 minutes before training. Nevertheless, for best results, follow the recommendations on the bottle and listen to your body.
Side effects have not been shown to be a problem as citrulline malate is reported as well tolerated. Clinical results have been detected by the third to fifth day after start of administration, which demonstrates citrulline malate is relatively rapidly acting.
Published with permission, by Travis Smith. Original ©
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Bendahan, D., Mattei, J. P., Ghattas, B., Confort-Gouny, S., Le Guern, M. E. and Cozzone, P. J. (2002) Citrulline/malate promotes aerobic energy production in human exercising muscle. British Journal of Sports Medicine. 36 (4), 282-289.
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These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.