L-arginine has several names: Arginine Ethyl Ester HCL, arginine HCL, arginine hydrochloride, di-arginine malate, di-arginine orotate, di-l-arginine-l-malate, di-arginine, l-arginina, l-arginine ethyl ester dichloride, l-arginine HCL- l-arginine hexanoate, l-arginine hydrochloride, l-arginine ketoisocaproic acid and R-Gene 10. This isn’t a comprehensive list of all the names of l arginine.
L-arginine is used for cardiovascular conditions including congestive heart failure (CGF), angina pectoris, hypertension and coronary artery disease. There are several other medical conditions that arginine is used to treat; however, we are interested in the use of l-arginine for improving athletic performance and we are interested in its ability to improve immune function.
In clinical studies, l-arginine has been used safely with only minor side effects lasting as short as a few days and as long as 3 months. There is insufficient evidence for long-term safety of arginine when used past 3 months since it hasn’t been studied longer than 3 months in the clinical studies.
In pregnant women, 12 grams of arginine has been used safely in women for up to 2 days that have a gestational length of 28 to 36 weeks. Lower doses have also been used for up to 3 weeks. Avoid using arginine during lactation.
In a study published in the Journal of Applied Physiology it was found that 6 grams of l-arginine dissolved in 500 ml of a beverage taken one hour before exercise reduced the O2 cost of moderate-intensity exercise and blunted the VO2 slow component and extended the time to exhaustion during severe-intensity exercise.
Systolic blood pressure and diastolic blood pressure were also reduced in the group supplementing with arginine compared to placebo. L-arginine works by increasing nitric oxide availability. These results are consistent with a previous study that proved arginine supplementation improves exercise efficiency and exercise tolerance in healthy humans. That’s two studies confirming the dietary benefit of arginine supplementation. It is believed that the mechanism responsible likely has to do with an increased muscle oxygen supply and direct effects of nitric oxide on muscle contractile efficiency and/or mitochondrial function but this remains to be researched in more depth.
Because arginine supplementation results in the production of nitric oxide it is useful in the treatment of conditions such as chest cramping (angina), high blood pressure, heart disease and sexual dysfunction. It does this by its ability to cause what is known as vasodilation. When you vasodilate, your blood vessels swell open allowing more oxygen to transport more readily. For example, angina results when your coronary arteries are blocked preventing oxygen flow to the heart. When nitric oxide is available your coronary arteries will open up wider, allowing more oxygen to flow to the heart, which improves angina. With weightlifting, it is believed that the increased vasodilation experienced helps people gain healthy and large pumps. Pumps results when nutrients and oxygenated blood flow into the muscles making them appear much fuller and bigger than usual.
What is interesting is supplementation with l arginine and the growth hormone response. Studies have shown that resting levels of growth hormone increase with ingestion of 5-9 grams of arginine. Resting growth hormone levels increase at least 100%; however, exercise increases growth hormone by 300-500%. When exercise and arginine are combined, growth hormone levels diminish to only 200% compared to resting levels.
Is having your growth hormone levels elevated at rest by at least 100% worth having a diminished growth hormone response to workout? That is the question. It is difficult to measure that and we’d need to know how long growth hormone is elevated following exercise with arginine and without arginine to make up an answer.
know that many bodybuilders are fond of their supplementation of l-arginine
especially since it can improve your pump. I would tend to think that you are
better off supplementing with arginine than without just because of how popular
it is with the bodybuilding community. I would be highly surprised if
bodybuilders such as Ronnie Coleman and Jay Cutler didn’t take l arginine.
Another interesting fact has to do with growth hormone. Bodybuilders such as Jay Cutler and Ronnie Coleman take a lot of growth hormone. It is possible that they can afford to take in less growth hormone from arginine and exercise because they supplement directly with injectable growth hormone. To answer this we’d need to know if more growth hormone is always better. With some drugs, when you add more, there is no more added benefits because we reach a point in which more drug has no added benefit except for more side effects. If this were the case then you wouldn’t be hurt be losing a little growth hormone because you already have a saturated maximum level reached with the use of exogenous growth hormone. If you are a natural bodybuilder, you may not want to take l-arginine if you workout everyday because it may diminish the total amount of growth hormone you have circulating at any given time.
L-arginine is a controversial supplement. A lot of people take it but it is difficult to tell if it is really worth it unless you take it yourself. From my supplementation with it, I wasn't disappointed in the benefits. I felt fuller pumps and improved exercise capacity from it. I also even feel a little better as if it causes euphoria. The expensive supplements that cause you to get fuller pumps are simple supplements that increase nitric oxide production in the body.
By buying l-arginine directly and taking it as a supplement you avoid the cost of those expensive supplements that are doing basically the same exact thing.
The clinical research supports the use of l-arginine improving exercise efficiency and tolerance; however, the clinical research also shows that you don't produce as much growth hormone when exercising while supplementing with l-arginine compared to just exercising without l-arginine. We want growth hormone because it results in increased lean muscle mass by burning fat and promoting muscular gains.
It may not really be worth supplementing with if you aren't exercising every single day with quite a few reps but for those taking it more seriously, I don't think it is such a bad idea to use l-arginine. It is definitely not a subtle difference, it is quite a noticeable difference and it is fast acting. It also supports cardiovascular health by decreasing blood pressure and by allowing more oxygen to flow towards the heart.
If you are wondering what dose to take, from the clinical studies, it looks like an effective dose is 6 grams of arginine taken one hour before exercise. This should increase your exercisability. You may not be disappointed with l-arginine supplementation.