Everything You Need to Know About L-Arginine Supplements

Reading time: < 7 min

L-arginine is probably one of the most well-known supplements in the world.

Unlike some of the other supplements that you might be aware of in the marketplace, L-arginine is a “pre-workout” substance. That means that you take it before you to the gym, to improve your energy levels, enhance your stamina, and help you accomplish more in your Marc Dressen fitness sessions.

Of course, pre-workout supplements haven’t always been an essential part of the fitness routine. In fact, there was a time when the only thing you’d do to prepare for your exercise regimen, is drink a glass of water or grab a cup of coffee.

So, why do we use these supplements now?

The simple answer is that studies were conducted which told us that taking the right enzymes and nutrients before a workout (such as L-arginine for instance) could potentially help us to improve physical performance without all the threats associated with standard stimulants.

Since we learned that pre-workout supplements can be helpful to the average fitness enthusiast, countless new options have hit the market. That means that many people are left wondering whether L-arginine is still worth the effort. By the time you reach the end of this article, you’ll know the answer.

Defining L-Arginine: The Classic Pre-Workout Supplement

L-arginine is an essential amino acid commonly found in the human diet. It comes in pretty much any food that contains protein, and it isn’t really associated with any deficiency state that’s linked to the modern world.

This substance is used in dietary supplement pills because it interacts with a molecule in your body called “nitric oxide”. This gas exists in your blood vessels for short periods of time, where it can improve blood flow, and even enhance stamina.

L-arginine was the first “nitric-oxide” boosting solution to hit the market. Although research found that this substance was useful for workout purposes, later studies also proved that L-arginine might not be as good at helping you achieve your goals as other compounds that can be used to increase the production of nitric oxide in the bloodstream.

How Does L-Arginine Work?

People supplement with L-arginine because the substance helps to enhance blood flow during exercise routines. This can be useful when it comes to reducing things like muscle soreness and ensuring that you have enough nutrients flowing throughout your body at any given time.

Commonly, L-arginine is sold in the form of L-Arginine AAKG. There’s nothing particularly fancy about this substance, but studies show that while it does work in some cases, it might not be effective all the time.

Instead, experts in the health and fitness industry are beginning to suggest that if you want to get all the benefits of a nitric-oxide boosting substance into your system using supplementation, then you might be better served using L-citrulline instead.

The Difference Between L-Arginine and L-Citrulline

When you take an L-arginine supplement and your body uses that substance, it’s transformed into L-citrulline. This new molecule then goes down into the kidneys, where it can be transformed back into L-arginine. That combination of amino acids, along with L-ornithine – are all important players in regulating the levels of ammonia and nitrogen in your body during a workout.

If you increase your levels of L-arginine, then the levels of L-citrulline in your system will heighten too, and vice versa. What’s more, when it comes to the receptors that these substances appeal to, both options are equally effective, because L-citrulline transforms into L-arginine, making the molecules the same.

The reason that L-citrulline is better for helping you to achieve measurable results, is that it’s easier for your body to absorb it.

When someone takes an L-arginine pill, the amount they absorb from that pill is generally all over the map. The more you take of the substance, the less you absorb, but most statistics suggest that you end up with a rate of absorption that ranges all the way from 70% to 20%.

Whatever your intestines can’t absorb from your supplement simply goes into your colon, where the substance can begin to cause unwanted side-effects like colon and cramping. On the other hand, L-citrulline is absorbed in a more controlled way, using more transporters with an absorption rate that’s as close to 100% as possible.

The bottom line is that when it comes to nitric-oxide improving substances, you’re less likely to get negative side-effects with L-citrulline than you are with L-arginine.

What are the Main Side-Effects of L-Arginine

Speaking of side effects, if you do decide to take L-arginine, then you should make sure that you know exactly what you’re getting into. The most common side-effect of this substance is diarrhoea. Loose stool is one of the most common reasons why people have started to take L-citrulline more commonly than L-arginine.

When L-arginine ends up in the colon, it can promote nitric oxide production, which draws ions within the colon, followed by water. This pushes for a greater chance of diarrhoea in the same way that magnesium can induce bowel problems.

Because L-citrulline can be absorbed more thoroughly by the intestines and needs to go through the kidneys before it becomes activated, it’s unlikely to cause the same level of stomach problems. However, it’s worth noting that there’s always a risk of side-effects with any supplementation, so keep an eye on any symptoms that might appear when you change your diet.

Finishing Thoughts on L-Arginine

When L-arginine first emerged on the scene as a pre-workout supplement, exercise professionals thought it was the best thing ever for improving performance and endurance. The substance carried a lot of information into the fitness world about the importance of nitric oxide, and how this simple gas can improve our wellbeing.

However, though L-arginine did change the fitness world as we know it, it’s not necessarily the best option for supplementation anymore. The evidence seems to suggest that L-citrulline is clearly a better choice if you’re looking for a nitric oxide booster that’s unlikely to cause any dangerous or unwanted side effects.


Marc Dressen
Personal Trainer London

★ SC: marcdressen
★ IG: http://instagram.com/marcdressen
★ FB: http://facebook.com/marcdressenpt
★ TW: http://twitter.com/marcdressenpt
★ G+: https://plus.google.com/+marcdressenpt
★ YT: http://goo.gl/VJT31c

Image Source: Pixabay