Glutamine is known for its capacity to increase strength, resistance and muscle recovery. Less known, but no less important, are its properties to support the immune system, increase concentration and memory and adjust the pH.
Even if produced by our body, it is considered a conditionally essential amino acid. This is because, in particular conditions such as stress and intense physical activity, the stocks are used up so that supplementation is required.
Glutamine is used mainly to favour recovery after an intense effort and to fight the over-training syndrome (chronic fatigue, loss of weight, loss of appetite, small infections, nausea, depression, apathy, increase of the heart rate when both resting and training).
In fact, it can increase access into the cells of water, amino acids and other substances that allow nourishing and restoring stocks. This action would stimulate protein synthesis too, promoting the increase of the muscle mass and inducing the anabolic state. This seems to be caused by the stimulation of GH (growth hormone) and GABA (gamma-Aminobutyric acid) production. Its ability to form muscle glycogen, contributing to energy reserves, is also important.
Glutamine can also act at central level since it can cross the blood-brain barrier and reach the brain where it is converted into glutamate. In this form it acts on the perception of fatigue raising the threshold, increases mental alertness and improves the mood and memory. All important factors, above all for sportsmen that must face long training.
Moreover, glutamine plays a good detoxing role, eliminating nitrogenous waste, and can regulate the blood and urine pH. During the effort, our muscles produce catabolic substances that tend to acidify the blood. The drop in pH is noticed by the kidneys that trigger a chain of reactions involving glutamine in order to neutralize the acidifying compounds. In this case, the glutamine used is the muscle glutamine and it is for this reason that it is said that acidosis gets rid of muscle glutamine.
Its intervention in the formation of glutathione, the most powerful anti-oxidant produced by our body, is important. Glutathione manages to eliminate the free radicals that are formed during physical exercise.
Glutamine acts first in the intestinal tract, where it sustains macrophages and lymphocytes, that are the cells of our immune system. An activity that makes it an important support in our body defences.
Passing through the intestine causes a 60-70% reduction in the absorption in the blood in comparison with the quantity taken by mouth. It would seem that in its peptide form, glutamine loses this function but that it increases the percentage found in the blood after ingestion up to 10 times.
In nature, glutamine is found in many animal (meat, fish, eggs and dairy products) and vegetable products. There is no shortage of food supplements that contain it in different forms and compositions, to meet everybody's needs and preferences.
Taken in the dose of 5g a day, after physical exercise, glutamine is a superb physical and, why not, moral support for all sportsmen!
Dr.ssa Olga Meletis
Farmacista specializzata in nutrizione sportiva