L-arginine Benefits for Bodybuilders

L-arginine, is a semi-essential amino acid. The human body is not able to naturally produce sufficient amounts of L-arginine on its own. This means supplements and foods rich in arginine (raisins, peanuts, almonds, chocolate and other nuts and seeds) are needed to satisfy the body’s requirements.  
Along with bodybuilders, L-arginine is also quite beneficial to growing children, infants, dieters, the elderly, and other athletes. The amino acid helps boost the immune system, increases blood flow, lowers blood pressure and helps repair muscle. 

L-arginine molecule
L-arginine molecule

What is L-arginine?

The amino acid L-arginine helps the body build proteins and release nitric oxide in the bloodstream. Arginine is considered to be a semi-essential amino acid, this means that the human body produces some amount of l-arginine on their own.

Normally, these amounts are sufficient for a human body to function normally. It may be beneficial to consume additional L-arginine in certain circumstances, such as muscle building, vasodilating, and improving fitness performance. 

L-arginine Benefits for Bodybuilders

In the world of bodybuilding, there are numerous different ways to get L-arginine, such as consuming arginine-rich foods or taking Arginine supplements. These will help an individual better attain their fitness or bodybuilding goals. The following are the main ways that L-arginine can benefit bodybuilders:

Nitric Oxide

In the body, L-arginine is converted to a chemical called nitric oxide. Through the formation of nitric oxide, the blood vessels open wide and make it easier for the blood to flow.

The neurotransmitter nitric oxide is highly potent and it is known that it has the ability to relax and dilate blood vessels and this helps improve circulation as well. Since it is one of the most effective supplements to raise levels of nitric oxide, L-arginine is a highly effective supplement for exercise.

It mainly increases circulation and promotes improved blood flow, which is essential for improved endurance. By increasing the blood flow and circulation to the working muscles provides them with an increased supply of oxygenated blood, as well as helping them get rid of lactic acid. This is a byproduct of energy production.


The vasodilating capabilities of L-arginine help boost muscle growth. Vasodilation is a process that causes the blood vessels in the body to widen after the smooth muscle in the vessel wall has become relaxed. In turn, blood pressure is reduced because there is more space for blood to freely flow.

Arginine is an immediate precursor to nitric oxide. The molecule nitric oxide, also known as NO, is an extremely powerful signaling molecule. It has the potential to operate as both a second messenger and an intercellular messenger responsible for regulating vasodilation.

Muscle Building

L-arginine is popular among fitness enthusiasts and bodybuilders because of its ability to improve protein synthesis, which means essential proteins are created, equating to better repair and results from workouts.

Arginine contributes to muscle growth because it acts as a precursor to nitric oxide. It has been suggested that L-arginine may act as a muscle-building supplement because of its functions in the body, such as vasodilation. This is largely due to its relationship with Nitric Oxide (NO). Vasodilation is achieved by releasing nitric oxide, which relaxes and opens blood vessels.

The body makes proteins from arginine, including muscle proteins. L-arginine serves as a building block for most proteins, so it contributes to muscle growth.

Cell research suggests that arginine has similar properties to leucine in triggering muscle building. Arginine stimulates the release of growth hormones and insulin in the muscle cells, which promotes fat metabolism and increases energy levels. As a result, you will gain lean, toned muscles.


Since nitric oxide dilates blood vessels, it contributes to a healthy circulation of blood. The better your blood flow in your body, the more oxygen you provide to your working muscles. This will lead to better performance.

In reality, your body delivers just the right amount of oxygen by itself without Arginine, but taking l-arginine supplements can provide your body with a small boost, by increasing blood flow to your working muscles and therefore improving your performance and endurance.

L-arginine Side Effects

L-arginine supplements may cause side effects. The most common side effects seen with L-arginine supplementation are

  • nausea
  • diarrhea
  • weakness
  • low blood pressure.

Most side effects are because the individual is taking too much Arginine. Most of the side effects can be avoided by following the proper dosage that is recommended by the manufacturer or by your doctor.

L-arginine Dosage

Bodybuilders usually consume 2 to 30 grams of L-arginine per day, but there is no standard dosage. It is prudent to start with a low dosage of 3 to 5 grams daily, taken before and after exercise, to reduce the risk of side effects such as nausea, diarrhea, and weakness.

Within one week, you will increase the dose at a point where you will obtain the maximum benefits, and minimize any side effects. L-arginine supplements should be alternated between a two-month hiatus and a two-month resumption.

It’s always better to build up to L-arginine gradually. Although there’s no standard dose set for L-Arginine, your body needs to adjust to it, so you should gradually increase it.

Summary L-Arginine Benefits for Bodybuilders

Overall L-arginine is a solid supplement to add to your muscle building supplement regiment. It is not going to pack on pounds of muscle, but it will help you train harder and recover faster mainly due to the improved circulation and blood flow during your workouts and post workout.

Before including an L-arginine supplement into your regular routine, it is wise to consult a physician, especially if you already deal with existing heart or psychiatric conditions. It is also imperative to follow recommended doses, as overdosing can easily occur. 
Overall, it is wise to follow the dosage recommendations printed on the outside of product labels. It is also wise to check the labels of protein powders and other supplements you may take, where added amino acids may already supply arginine. This will help gauge a more accurate daily intake.