Glutamine 101

in Sportsfuel Articles and Blog
Glutamine 101

Glutamine is the most abundant amino acid that is naturally found in your body. It is one of 20 non-essential amino acids. I know, you’re thinking - So then why should I take a glutamine supplement? Read on to find out what glutamine is, how it is used, and why it is one of the best post-workout supplements you can take to aid your recovery and general health.

What is Glutamine?

Glutamine is the most abundant amino acid that is naturally found in your body. It is one of 20 amino acids that are called non-essential. This means that the body can construct or make glutamine on its own from already available compounds in your body whenever it thinks is necessary. Good food sources of glutamine come from quality protein-rich foods such as fish, steak, poultry, dairy products and beans. But the fact that glutamine belongs to the non-essential group of amino acids doesn’t mean you should disregard its importance as a supplement. It is the primary fuel source for boosting your immunity and a big part of it is stored in your muscles.

Studies have shown that stressful events such as intense workouts or illness can cause your muscles to release glutamine into the bloodstream. This can deplete your reserves by up to half of their total amount. Glutamine depletion can cause muscle tissue to start breaking down. The amount of depletion of glutamine is mostly influenced on how intensive your workout was. In the most extreme cases, catabolic (muscle break down) circumstances experienced by burn patients can have a depletion effect by as much as 90%. At the lower end, recreational lifters or gym users would have a slight drop in their levels. In the middle, serious athletes or gym users training at high intensity or for long periods of times will usually use around 30-50% of their glutamine stores each workout. Basically, the greater the workout effort, the more glutamine you use. This is why experts think of glutamine as a non-essential amino acid, as it depends on the intensity of your workouts.

How does it work?

Glutamine plays a part in many different functions within your body. It helps with muscle growth and recovery, as well as supporting your immune system. It does not get stored the same way fats or carbs, it becomes whatever the body needs it to be. Mostly the body needs it for the purpose of building and maintaining muscle tissue.

Glutamine’s form is changing all the time. It can be a part of a cell membrane, and other times it can be a part of a hormone or an enzyme, whatever the body needs it to be. Glutamine levels will rise or fall depending on your body’s daily requirements. This emphasises the importance of glutamine supplementation after a hard workout. If your glutamine levels become 50% depleted, then there will not be enough glutamine to do everything the body needs. Your body will not be able to get the glutamine to build and repair muscle as well as support your immune system, as there will not be enough reserves.

Research has proven glutamine helps increase muscle recovery after exercise. It is always readily available – this prevents muscle breakdown and prevents muscle tissue from being used by your body, which is known as “protein sparing” in the bodybuilding community. Protein sparing is when the protein in your muscles is spared from being used as an energy source. The primary energy source when it comes to exercise is glycogen, which is derived from the breakdown of carbohydrates. Once your body has used up its glycogen stores, it will turn to the protein in your muscle tissue as a secondary energy source. This means your body will begin breaking down those hard earned muscles to fuel your current activity. Glutamine prevents this by increasing the production of glycogen to refill your glycogen stores and thus sparing the protein in your muscles from being used. The protein in your muscle tissue can then be used for muscle growth and recovery which is far more ideal.

Glutamine has been proven to be crucial for hydration of the cells in your muscles, which helps them maintain their volume, which increases protein synthesis - the rebuilding and repairing of muscle tissues. Glutamine enters the cell, draws water into it and gives it volume. The hydrated cell is harder to be broken down which helps you maintain your muscle mass.

Glutamine protects the immune system by being the number one energy source for the immune cells. If the immune cells cannot find enough glutamine in the body to make the necessary repairs, they will start breaking down the protein in your muscle tissue. By supplementing with Glutamine you ensure that your immune cells will always have adequate fuel to make repairs and this will prevent unnecessary muscle breakdown. Glutamine also helps your training by boosting your immune system to fight off any infections which can prevent you from training and make you weaker.

When you work hard in the gym you can cause extensive muscle damage which your immune cells repair in order to facilitate muscle growth. Since immune cells use glutamine as their main source of energy it is important there is an adequate supply available. Say you just did an intense bicep workout. If the immune cells can’t get enough glutamine because you’ve just depleted your reserves while working out, the cells will start looking to the glutamine in other muscles like your abs, thighs or shoulders so it can repair the bicep muscles.  Taking glutamine can increase muscle recovery and prevent the breakdown or catabolism of muscle tissue as a result of a hard training session.

Who can benefit?

Your body’s need for glutamine increases when you are under stress, after a heavy workout, illness or an injury. If you aren’t pushing yourself very hard at the gym, or you’re doing less intensive exercises like walking or yoga, then your body can probably provide enough glutamine by itself. If you’re training hard at the gym, or carrying out intense physical activity on a regular basis then glutamine can help you reach your goals.

Two specific groups of people who can benefit from glutamine are:

  1. Bodybuilders or physique competitors.

Dieting for a show involves getting your body fat percentage as low as possible, at least into single digits. This can be really stressful for your body, and can deplete your protein and glutamine stores. Muscle breakdown can increase significantly if the immune system does not have an adequate supply of glutamine available to fuel the immune cells. Your body is more susceptible to this when you are in the process of continuous training leading up to a show. Another benefit that may appeal to bodybuilders or physique athletes is that glutamine can lower your cravings for sugar. A low dose of 1.5mg between meals can make a huge difference when you are cutting for a competition.

  1. Endurance athletes.

It’s been found that distance runners are more likely to catch a cold or other respiratory infection than an average bodybuilder. Glutamine supplementation can boost distance runners immune systems to prevent them from falling ill, and also help support their recovery after training.


The best time to take glutamine is post-workout, since your stores of it are at their lowest level having been depleted from the training you’ve just done. If you are doing a longer workout session (over 90 minutes) or are on a low carb diet, you may want to take it pre-workout as well to ensure your body produces enough glycogen to use as a fuel source and prevent muscle breakdown.

Taking glutamine in a powder form is convenient and relatively inexpensive. You can buy flavoured or unflavoured glutamine. The benefit of unflavoured being that you can mix it into your pre-workout or post-workout drink. The general recommendation is to dissolve 3-6g into water along with a quality when protein powder and consume after your workout. You can also add BCAA’s to this post-workout drink to aid muscle recovery.

Mixing glutamine with hot liquids is not recommended as the heat destroys the glutamine molecule.

Check out our range of glutamine supplements here.



Leave a comment

Please note, comments must be approved before they are published