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Glutamine and its affect on athletic performance

What is glutamine?

Glutamine is a non-essential amino acid that helps your immune system and intestinal organs function.

During intense blocks of training, glutamine levels can be reduced. This is what increases an athletes risk of illness.

The release of glutamine

When stress occurs to the body, the liver and skeletal muscles release glutamine to maintain immune function. Examples of stress are burns, physical trauma, starvation, intense physical activity and prolonged exercise (marathons, triathlons and other ultra-endurance events).


In the case of overtraining, the body can become depleted of glutamine – suppressing the immune system. This increases the risk of illness in endurance athletes.

Hard training blocks are part of endurance training.

Sources of glutamine

Glutamine can be found in your diet and is most prevalent in animal sources, such as beef, pork, eggs, chicken, milk products and fish. In plant-based foods, high levels of glutamine are found cabbage and beets. Other sources include beans, barley and nuts.

Related: Three supplements to help maintain health

Why athletes supplement their diet with glutamine

The reason why athletes supplement their diet with glutamine is to avoid illness and muscles breakdown (extreme levels of training). Within the scientific literature, numerous studies show that endurance athletes who supplement their diet with glutamine decrease their risk of illness.

Pictured above are some sources of glutamine.

The roundup

With a balanced diet of greens and protein, most athletes do not need to take a glutamine supplement. However, if your training load is abnormally high and your diet is unable to meet your needs, then supplementation may be beneficial.