Exercise can lead to a decrease in plasma glutamine levels. Studies have shown that power athletes can have particularly low plasma glutamine. It also affects endurance athletes –after running a marathon, glutamine levels are low for 6-9 hours. Low plasma glutamine is an indicator of overtraining. Glutamine has been linked with the following:

• Improved gut barrier function and reduced risk of endotoxaemia
• Nutritional support for immune system and prevention of infection
• Stimulation of muscle glycogen re-synthesis
• Stimulation of muscle protein synthesis and muscle tissue growth
• Reduction in muscle soreness and improved muscle tissue repair

Glutamine deficiency has been observed after surgery, burns and other stresses as well as exercise. For this reason it is called a conditionally essential amino acid.

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