A: For athletes, plasma glutamine level is an important index to evaluate whether they overtraining. When bodybuilders and other athletes engage in high-intensity strength training, the glutamine level in the body can be reduced by 50% (it will take several hours to recover to the original level). At this time, if you can't get enough glutamine through diet or self-synthesis, you will decompose muscle protein to meet the body's demand for glutamine. This not only affects the volume of muscle, but also reduces the immune ability of the body, because glutamine in the immune system is mainly released from skeletal muscle. After a long period of exhaustive exercise, the plasma glutamine level is even lower, and some people may maintain the low level for weeks, months or even years.

Glutamine supplementation can prevent this decline. The short-term effect of exercise on plasma glutamine level can be accumulated, so it takes a long time to recover from the low plasma glutamine level (below 500umol/L) caused by intensive training.

Studies have shown that timely and appropriate supplementation of glutamic acid can effectively prevent the decomposition of muscle protein, increase cell volume and promote muscle growth through cell hydration. Glutamine is also one of the few amino acids that can promote the release of growth hormone. Studies have shown that taking 2 grams of glutamine orally can increase the level of growth hormone by 4 times, increase the secretion of insulin and testosterone, and thus enhance muscle synthesis.

Glutamine has a powerful effect. During exercise, the increase of acidic metabolites in the body acidifies the body fluids. Glutamine has the potential to produce bases, so it can alleviate the decline of exercise ability or fatigue caused by acidic substances to some extent. Another study suggests that glutamine can aggregate muscle glycogen.

To sum up, glutamine supplementation has many benefits to the exercise body, especially to the growth of muscle cells and the improvement of immune function. This is a good restorative after strenuous exercise. Therefore, if bodybuilders want to achieve the best training effect and keep their muscles growing, they should supplement glutamine while taking enough protein.