L-Arginine isn’t anything new. I mean, it’s been used by men for decades mostly for treatment of erectile dysfunction (ED) – a case where places that are meant to harden now remain “soft” and “mushy” if you catch my drift. Yeah, it’s true. Ask your grandpa.
All kidding aside though, L-Arginine is a supplement that holds great potential for manly health. As I’ve said, it’s been used to treat none-standing penises but it’s also added to some testosterone boosters for the same reasons. What are these reasons, you ask? How about we get to the research review first.
WHY TEST BOOSTER SUPPLEMENTS USE L-ARGININE
There’s so much more to L-Arginine than just erecting penises. In fact, the same reason why it’s able to do this is the same reason why it’s used not just in testosterone boosters but also in bodybuilding supplements. I’ll get to that in a sec but first, allow me to shed more light on what L-Arginine is.
What is L-Arginine?
L-Arginine, or Arginine as others may call it, is a semiessential or conditionally essential amino acid. This means that it can also be produced by our own bodies but is typically found in low concentrations, and thus the need for external sources. Speaking of external sources, L-Arginine can be found in protein rich foods such as beef, chicken, turkey, eggs, fish, and even dairy products such as milk and cheese.
As all amino acids are, L-Arginine is a building block for protein. Additionally, L-Arginine can be converted into Nitric Oxide which can be used by our bodies to improve circulation via vasodilation.
And now that you know what L-Arginine is, let’s get to the good parts of that blue box above and focus on circulation and vasodilation. These effects can be taken advantage of by our bodies in a few things such as influencing cardiovascular and cerebral function which makes it a pretty good supplement for both heart and mental health.
But that’s not what you’re here for, isn’t it? In terms of bodybuilding and testosterone boosting, L-Arginine enhances blood flow to our manly parts. And by that, I don’t just mean our sexual organs but also to our muscles. Strictly in terms of testosterone though, the pathway that L-Arginine takes is somewhat an indirect way to boost our manly hormone. Let’s jump on the researches and find out some more.
STUDIES ON L-ARGININE SUGGEST:
Before we get to that, I’d just like to point out that there really isn’t much human trials done on this amino acid. However, there is quite a bit of animal research that surrounds L-Arginine. This is bad in a sense that neither me nor the scientists who conducted these researches can say for sure if the results of these animal studies cater to human physiology as well. On the bright side though, these researches can be used to somewhat make a hypothesis on how it might work for us, too.
Regulate testicular blood flow and testosterone
A research was conducted on male Sprague-Dawley rats to determine the effects of L-Arginine on testicular blood flow and serum steroid hormones. After taking baseline measurements, the rats were then given L-Arginine at a rate of .50 mg/kg per minute for 10 mins. After 24 hours, measurements were taken again and compared to the baseline values. These are the results of the research:
- Significantly increased heart rate, testicular blood flow, and Nitric Oxide
- Insignificant difference to progesterone and corticosterone
- Significantly increase in the concentration of testosterone
As you can see from those results, L-Arginine was already able to markedly increase levels of nitric oxide, testosterone, and blood flow to the testicles in just a matter of 24 hours. According to the research, these results “indicate that the synthesis of NO through NO synthase may play a role in the regulation of testicular blood flow and the serum levels of testosterone”.
Another research was done to study the influence of dietary arginine on the anabolic effect of androgens. Yes! Anabolism and androgens in one sentence! That basically means that the research was done to observe the muscle building benefits of boosted testosterone via L-arginine supplementation. Unfortunately though, this research was (again) done on mice but the concept still is pretty cool.
The research was conducted by simply feeding mice an arginine deficient diet and then measuring the effects of arginine depletion. Results of the study are as follows:
- Decreased arginine, citrulline, and ornithine in females
- Decreased arginine in males
- Decreased body and renal weight in males
- Opposite effect in IGF-I and IGF-binding protein 1 expression in the liver and kidney
In addition to these, the researchers also found that the arginine restricted diet “prevented the body weight gain induced by testosterone treatment of female mice fed the standard diet”. That plus the observed decrease in arginine and body weight in males, and the observed change in the IGF, suggests that L-Arginine might play an essential role in the anabolic effects of testosterone by mediating “changes in the insulin-like growth factor system”.
Increase in exercise related hormones except testosterone
The first research is about the effects of arginine and ornithine on hormones after heavy resistance training. The study was done by comparing the results of a placebo group and another group supplementing L-arginine and L-Ornithine. Serum levels of hormones including testosterone, cortisol, growth hormone, IGF-1 and insulin were recorded on both groups. Here are the results of the L-Arginine plus L-Ornithine group as compared to placebo:
- Significant increase in growth hormone and IGF-1
- No differences were observed in other hormones
The next research is on the influence of chronic arginine supplementation on endurance athletes. The research was done by dividing the participants into three groups depending on how much L-Arginine they are given:
- High concentration using 5.7 g arginine
- Low concentration using 2.8 g arginine
Similar to the previous study, hormones were measured including growth hormone, testosterone, and cortisol. After the study, the researchers found that L-Arginine supplementation did not produce any significant change to exercise performance and hormonal levels and further said that regardless of dosage, they did not see any “apparent reason why the supplementation of arginine aspartate should be an effective ergogenic aid”.
As you can see, the animal research and the human research sort of contradict each other but if you really think about it, there’s a way to make sense of all these. As the rat research has shown, L-Arginine promoted testicular blood flow and had a pretty clear influence on anabolism as evidenced by the loss of body weight in the male rats.Next, the two human studies showed that while L-Arginine didn’t increase levels of testosterone, one research was able to show an increase in levels of human growth factor.
Here’s my take on this. L-Arginine does not have ANY direct testosterone boosting capabilities but might be able to do so through indirect ways. Simply speaking, it increases levels of growth factor leading to more muscle. And with more muscle, your body might also produce more testosterone. The potential boost in testosterone might also be due to the enhanced circulation to your testicles as suggested by the rat study.
How Do I Take L-ARGININE?
Personally, I’d say take around 15-18 g of L-Arginine per day for maximum effects. Also, you might want to divide the total dose to 3x per day as taking in more than 10 g in one serving have been observed to cause side effects like diarrhea and gastrointestinal discomfort and no one really wants that.
In my observation during my time writing reviews for testosterone boosters, supplements may dose L-Arginine to somewhere around 3-9 mg. Taken 3x per day, that’s 9-18 mg per day. Like I said though, I’d personally aim for at least 15 just because L-Arginine is known to be a poorly absorbed amino acid.
Well, to end this, the testosterone boosts it potentially has on humans is purely theoretical at this point. While it does show some promise in animal research, more human trials still need to be conducted. As such, don’t expect too much boost in testosterone if you’re only taking L-Arginine.
Thankfully though, L-Arginine is usually part of pre-workout bodybuilding formulas. If it doesn’t satisfy your need for boosts in testosterone, maybe some of the ingredients in the formula will while L-Arginine helps “pump” your muscles with the needed nutrients for anabolic muscle growth.
In testosterone boosting formulas, the nitric oxide boosts that it provides is there to help out health-seeking men as well. By inducing vasodilation and enhancing circulation, your man parts get the blood flow it needs to satisfy your woman in bed. Also, the increased blood flow to the testes could potentially increase testosterone, too.
TESTOSTERONE BOOSTERS THAT USE L-ARGININE
- Testogen XR – A product of Ronnie Coleman himself, using a branded compound derived from Arginine
- Vitrix – More libido enhancer than testosterone booster, Vitrix uses L-Arginine in its sexual performance blend
- BioXGenic – A solid testosterone booster for sex and muscle using L-Arginine in its Hormone Releasing X Complex.
- Test X180 – Using Avena Sativa as a possible source of L-Arginine.
- HighT Black – Has 3 three forms of L-Arginine in A-AKG, A-KIC, and L-Arginine Monohydrate