Quick Arginine Summary Points
- Arginine is historically one of the most popular amino acids in bodybuilding
- Arginine is classified as a conditionally-essential amino acid, meaning that the body can manufacture it but it may become limited during times of demand or stress
- The high interest in arginine stems from its metabolic link with the production of nitric oxide
- Arginine also serves as a precursor to citrulline and creatine; both important substances in the context of sports performance
- Arginine is most commonly found in pre workouts, however, it can also be found in growth hormone boosters, where it is most commonly combined with lysine
What is Arginine?
Arginine is an amino acid that has been investigated for its potential properties in enhancing athletic performance. It is of interest to bodybuilders as it may increase "the pump", as well as athletes for its possible effects on improving endurance.
Under normal circumstances, arginine is synthesised in the body by a complex chain of reactions. Consequently, it is not strictly considered to be an essential amino acid. However, it's generally not synthesised in adequate amounts to meet the demands of most people, and a dietary source may also be necessary. It can be found in supplements, in lot of animal products such as meat and dairy, as well as plant sources such as nuts, seeds, and wheat.
Arginine & Nitric Oxide
One compound that is of a lot of interest to bodybuilders is nitric oxide (NO). Nitric oxide is a natural vasodilator, which means it is synthesised by your body to temporarily widen your blood vessels. This allows more blood to reach your muscles and give you what is known as "the pump". The pump make your muscles look larger, feel firmer, and the additional blood supply may aid in increasing endurance and weight lifting. Nitric oxide as a substance is considered a drug, is unstable, and is therefore not available to most people. However, arginine is the precursor to nitric oxide in the body, and being an amino acids means that it is readily available to everyone.
Arginine & Creatine
Creatine phosphate is a naturally produced molecule within the body that breaks to make more ATP (the currency for energy needed for muscle contractions). Arginine is involved in the body's process of making creatine. However, if you are looking to increase your creatine levels, it is better to be more direct in your approach and use a creatine supplement.
Arginine Vs Citruline
Citruline is the precursor to arginine. It has been said that supplementation with citruline may be more effective in producing nitric oxide than using arginine directly. Read more about this in our article on Arginine Vs Citruline.
Arginine Benefits for Growth Hormone
Studies have suggested that arginine, given along with its precursor, ornithine, is a strong stimulant for the secretion of human growth hormone (hGC) and other anabolic agents in untrained subjects (Butterfield, 1999). However, when given to trained individuals such as bodybuilders and weight lifters, arginine does not appear to help increase the already high levels of hGC within these people (Williams, 1999). However, this may be due to inappropriate mixtures and doses, as it has been found that arginine in combination with lysine is needed (Isidori et al, 1981). Thus, in regards to the effect of arginine on increasing anabolic hormones, it may be more effective if you are a beginner, looking to start bodybuilding or weight training. Once you become experienced, arginine supplementation alone may not significantly boost your hormone levels.
Arginine Benefits for Strength & Endurance
There has been some evidence in the scientific literature to support arginine as a performance enhancer. Elam et al (1989) reported that arginine along with ornithine was successful in being able to increase strength, lean mass, as well as experiencing improved recovery parameters. A more recent study found that a commercial arginine supplement, also containing vitamins C and E, was effective in increasing the endurance threshold of an elderly group of cyclists (Chen et al, 2010). It has been speculated that this works because of the effect arginine has on increasing nitric oxide synthesis, thereby causing vasodilation and increases in endurance.
It has been suggested that arginine may be beneficial in building lean mass when consumed in conjunction with other amino acids. As a result of the increased nitric oxide production, increased blood flow may help deliver additional amino acids to muscles needed for muscle anabolism and growth (Paddon-Jones et al, 2004).
Arginine Benefits for Erectile Dysfunction
Nitric oxide plays a major role in penile erection. Thus, it has been thought that arginine may be able to elevate erectile dysfunction. There have been numerous studies that have reported that arginine supplementation improved the condition of men suffering from erectile dysfunction. This effect also seems to be amplified when arginine is given in combination with pycnogenols (a pink bark extract) (MacKay, 2004).
Arginine Safety and Side Effects
Arginine is a common amino acid with the body and the food we eat. Consequently it is a very safe compound. Excess arginine is easily eliminated from the body, and few side effects are reported. It has been estimated that a 70 kg man would be able to tolerate up to 20 g arginine per day over a long period of time (Wu et al, 2007).
Arginine Recommended Doses and Ingredient Timing
Doses as low as 1 or 2 grams of arginine may help to increase exercise performance. This should be taken between half to an hour before training.
Arginine supplements come in three forms:
- Stand-alone – just a pure, good old arginine supplement. This can be taken pre workout to potentially increase nitric oxide synthesise and the pump.
- Protein and amino acid blends – some are considered to be "specialty and muscle building proteins" the arginine present in these products can help to deliver amino acids muscle tissue, which may fuel muscles for anabolism and rapid recovery.
- Pre workout supplements – many pre workout mixtures include arginine, as well as other amino acids, for the above mentioned reason. However you may also find ingredients such as caffeine and creatine to complement the potentially ergogenic effects of arginine.
Arginine can be stacked with other amino acids to help improve amino acid incorporation into muscles. It can also be stacked with citruline to increase pump during workouts.
Butterfield (1999), Amino acids and high protein diets. In Lamb DR, Williams MH (eds): Ergogenics: Enhancement of Performance in Exercise and Sports. Dubuque, IA, Brown and Benchmark, pp 87-122
Chen et al (2010), Arginine and antioxidant supplement on performance in elderly male cyclists: a randomized controlled trial. Journal of the International Society of Sports Nutrition, 7: 13
Elam et al (1989), Effects of arginine and ornithine on strength, lean body mass and urinary hydroxyproline in adult males. J Sports Med Phys Fitness, 29: 52-56.
Isidori et al (1981), A study of growth hormone release in man after oral administration of amino acids. Current Medical Research and Opinion, 7: 475-481
Paddon-Jones et al (2004), Potential Ergogenic Effects of Arginine and Creatine Supplementation. J. Nutr, 134: 2888S-2894S
MacKay (2004), Nutrients and botanicals for erectile dysfunction: examining the evidence. Altern Med Rev, 9: 4-16
Williams (1999), Facts and fallacies of purported ergogenic amino acid supplements. Clinics in Sports Medicine, 18: 633-649
Wu et al (2007), Pharmacokinetics and Safety of Arginine Supplementation in Animals. J Nutr. 137: 1673S-1680S