Does L – arginine help with health and sports?
L-arginine (abbreviated to arginine only) is a positively charged amino acid that is classified as semi-essential or essential in certain conditions. Every fitness enthusiast has heard of L-arginine, but few know that it neutralizes free radicals.
Arginine is most popular among exercisers due to its claims that it increases nitric oxide, which in turn stimulates muscle growth and athletic performance. While these properties can be defined as controversial, arginine has some health effects, which we will discuss in more detail.
Table of Contents
What is L-arginine?
In principle, the body can synthesize enough arginine to meet its own needs. However, there are several cases in which this is not the case.
Arginine is an essential amino acid for young children.
In stressful conditions such as trauma, burns and inflammation, arginine also becomes an essential amino acid for the adult body and it is therefore very important to get enough of it through food and / or supplements.
How is it produced / isolated?
Arginine is produced by fermentation using the bacteria Corynebacterium (Brevibacterium), Bacillus, Serratia and Escherichia coli.
Main physiological effects of arginine
Participates in the building of muscle tissue, being included in the composition of proteins, but there are many other actions.
How is arginine absorbed by the body?
After digestion, arginine is absorbed from the small intestine by active transport and enters the enterocytes, with a portion metabolized in them. The remaining absorbed part of arginine is transferred to the liver, where again one part is metabolized. The remaining amount of arginine is transferred to the great circle of blood circulation, from where it is distributed to various tissues in the body. The highest concentration of arginine in the blood plasma is observed about 1-2 hours after eating / taking a supplement.
Smaller doses of arginine are better absorbed.
When taking 6 grams of arginine, the bioactivity is about 68%. At a dose of 10 grams, the bioactivity drops dramatically to 20%. The intake of the amino acid as a dietary supplement successfully increases the plasma concentrations of arginine. Intake of 6 grams leads to an increase of 336% within an hour. Intake of 10 grams leads to the same increase, and intake of more than 12 grams does not lead to change. This is directly related to the decrease in bioactivity with increasing dose.
Why to take it?
Everyone needs to get enough arginine, and the groups with increased needs for this amino acid are adolescents, athletes, overweight people and the elderly.
Taking arginine by exercisers can boost the immune system, allowing them to exercise harder and avoid the unpleasant effects of overtraining.
Steroid users can also benefit from extra arginine intake, as these people often have elevated levels of “bad” cholesterol – a condition that improves with arginine intake. Overweight people, recovering from trauma, and those with erection problems would also feel better if they took arginine.
Proven and potential benefits in humans
Even when it is not an essential amino acid for the body, arginine has many other physiological effects because it:
- Moderate effect in increasing blood flow volume. It was thought to be a side effect of the increase in nitric oxide, but once this property was rejected, it was most likely due to another factor;
- It lowers blood pressure, but the effect is relatively weak. Studies that combine arginine with citrulline have found a more significant effect, especially in people with high blood pressure;
- Increases growth hormone at rest and after exercise. The effect is short-lived (1-2 hours) and there is no evidence of a general effect on the body;
- Increases plasma arginine levels. Peak levels increase dramatically, but L-citrulline is recommended for longer concentrations;
- Increases adiponectin levels and improves the ratio of adiponectin to leptin, but only in people with impaired glucose tolerance;
- It may improve anaerobic endurance, but has been found not to be due to increased nitric oxide levels;
- It is possible to increase the time to reach fatigue during exercise;
- It exhibits antioxidant properties and increases the levels of the antioxidant superoxide dismutase (SOD). Reduces oxidative processes. It is most pronounced in individuals with impaired glucose tolerance and type II diabetes;
- Improves endothelial function; It may improve fat burning with long-term use, but mainly in people with metabolic diseases and diabetes;
- Increases insulin secretion;
- Improves pancreatic function and insulin sensitivity, especially in people with metabolic diseases;
- Stimulates weight gain, but mainly in people with metabolic diseases;
- Improves the condition of claudicatio intermittens. This is a condition in which there is a sudden tiredness when walking;
- In combination with L-lysine suppresses anxiety, which is caused by severe stress;
Proven and potential benefits in animals and in vitro
- Significant benefits have been found in the protection of beta cells in the pancreas, leading to increased insulin secretion;
- In tests on rats, arginine was found to enhance the healing of skin layers in superficial wounds;
Optimal doses and route of administration
As a supplement arginine is taken from 3.5 to 15 grams per day. People with impaired heart function should consult a doctor before taking arginine.
A single dose of 3 to 6 grams is recommended before training.
To maintain arginine levels throughout the day, a total daily dose of 15 grams, divided into at least three doses, is recommended. As safe daily doses for arginine supplementation have not yet been established, take a low dose for one week, note the positive and negative effects, and then increase the dose until the positive effects are maximal and the negative effects are minimal.
Possible harmful / side effects
In case of overdose, diarrhea, general weakness and nausea may occur. Usually such effects occur at a dose above 10 grams. Due to the fact that arginine has poor degradability in the small intestine, the release of water and electrolytes can be provoked. This condition is called osmotic diarrhea. To minimize this effect, it is recommended to take up to 9 grams on an empty stomach or in the worst case with a snack.
It is possible that smaller doses of 3-5 grams provoke going to the toilet. 20 grams per day is the highest safe dose ever tested. You should take special care with arginine if you are taking the following medicines: ibuprofen, organic nitrates, sildenafil citrate. If you are taking yohimbine, you should know that arginine enhances its action.
Which foods contain arginine?
The main sources of L-arginine are plant and animal proteins. A small amount of free arginine is found in vegetable juices and fermented foods such as miso (soy cheese) and yogurt. Soy and other plant proteins are richer in arginine than animal proteins, which are richer in lysine. It is believed that at least in part the property of soy protein to lower blood cholesterol levels is due to the high content of arginine. Arginine is also found in large quantities in nuts and seeds such as peanuts and almonds, as well as in raisins and chocolate. You can see more about the content of arginine in food in the special section of our publication.
Forms of L-arginine
The most common form of the amino acid is L-arginine (free form). However, L-arginine is also the least digestible and least effective form.
Many sports products use Arginine Alpha-Ketoglutarate (AAKG).
It is a compound of arginine with an anionic salt that enhances the stability of the amino acid in the intestinal tract. Chloride salts such as aspartate, pyroglutamate and malate can have a similar effect. Although not a form of arginine, Citrulline Malate is considered its main alternative.
While arginine is superior to citrulline in increasing peak plasma levels, citrulline appears to be a more effective means of increasing total arginine levels throughout the body. If the goal is to maintain arginine levels throughout the day (erection problems, heart problems), then citrulline is a more reliable and effective supplement.
With what additives to combine arginine?
Arginine can be used in two main ways as a dietary supplement.
As a pre-workout, arginine can be successfully combined with dietary supplements such as ornithine, citrulline malate or nitrates (red beets).
To maintain amino acid levels during the day, arginine can be conveniently combined with the amino acid L-lysine. The two amino acids have synergistic properties and enhance the effect on each other. From BB-Team we are convinced that arginine can have its benefits as a pre-workout supplement, especially in combination with other similar substances such as citrulline malate, beta-alanine, acetyl L-carnitine and others.
In which products can we find arginine?
Arginine is often sold as a stand-alone dietary supplement. Its most popular forms are L-arginine (free form) and AAKG. Powder and tablet variants are available, but the powder has an unpleasant taste and smell. The latter is especially true of free-form arginine, something the Stayfitlonger – Team can attest to from personal experience. Arginine is almost always used in all pre-workout products and nitrogen boosters. In this case, the preferred forms are AAKG and Di-arginine malate.
Sources used :
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