Branched-chain amino acids (BCAA), including isoleucine (Ile), leucine (Leu) and valine (Val), are three essential amino acids that cannot be synthesized by human body and are the main energy-supplying amino acids of skeletal muscle. Bright amino acids can inhibit the degradation of protein. It has the function of delaying exercise fatigue. Some data show that amino acid metabolism, especially branched-chain amino acid metabolism, is closely related to the occurrence of exercise fatigue. Long-term exercise causes changes in the plasma amino acid spectrum, which leads to an increase in the ratio of aromatic amino acids (AAA) to branched-chain amino acids (BCAA), promotes the entry of AAA into the brain, increases the synthesis of 5- hydroxytryptamine (5-TH) in the brain, and causes central fatigue. Supplementing a certain amount of BCAA in exercise can competitively inhibit AAA from entering the brain and delay fatigue; At the same time, BCAA supplementation can promote gluconeogenesis and amino acid utilization in muscle tissue, save muscle glycogen, reduce muscle decomposition and play a role in saving amino acids in tissue repair. In addition, the research shows that branched-chain amino acids can alleviate the free radical damage caused by exercise, reduce the blood lactic acid concentration after exercise, and help stabilize the body's calcium concentration, which has a certain effect on fatigue recovery after exercise and can improve the body's exercise ability.

The recommended dietary amount of BCAA is 3g/d, which can be easily obtained from protein food. The safe supplement amount of BCAA is 5 ~ 20g/d, and a small dose of branched-chain amino acids (0.5g/h) is often used in long-term exercise, which has a good taste, is not easy to irritate the stomach, and can play a role in preventing the slight decline of blood branched-chain amino acids.

(1) causes an increase in blood ammonia; (2) it causes pyruvate consumption and affects aerobic metabolism to synthesize ATP(3) it stimulates the stomach and reduces the water absorption capacity; (4) Promote protein synthesis, but inhibit gluconeogenesis.

Glutamine is the most abundant free amino acid in muscle, accounting for about 60% of the total free amino acid in human body. The fasting plasma glutamine concentration is 500 ~ 750 umol/L. Glutamine is not an essential amino acid, but can be synthesized by glutamic acid, valine and isoleucine in human body. Under the stress state such as disease, poor nutritional status or high-intensity exercise, the body's demand for glutamine increases, which makes its own synthesis unable to meet the needs.

Provide necessary nitrogen source for the body and promote the synthesis of protein in muscle cells; Promote the growth and differentiation of muscle cells through cell compatibilization; Stimulate the secretion of growth hormone, insulin and testosterone, and make the body in a synthetic state. Glutamine is an important substance in immune system, which can enhance the function of immune system. Glutamine plays an important role in immune regulation and is necessary for lymphocyte secretion, proliferation and function maintenance. As the precursor and main energy source of nucleic acid biosynthesis, glutamine can promote the mitosis, differentiation and proliferation of lymphocytes and macrophages, increase the production of cytokines TNF, IL- 1 and the synthesis of phospholipid mRNA. In addition, glutamine is also involved in the synthesis of glutathione, an important antioxidant.

Glutamine is an essential nutrient for intestinal mucosal cell metabolism and plays a very important role in maintaining the integrity of intestinal mucosal epithelial structure. Especially under severe stress conditions such as trauma, infection and fatigue, glutamine in intestinal mucosal epithelial cells is rapidly depleted.

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.

Compared with other amino acid supplements, glutamine is relatively cheap.

It is suggested that sports drinks containing glutamine should be drunk on an empty stomach within 65438±0h hours after training and about 30 ~ 45 minutes before dinner. The dosage range of glutamine is 1 ~ 10g/d, and it is effective for athletes to take sugary drinks containing glutamine 3 ~ 5g after the competition to prevent post-exercise infection.

Taurine is a conditionally essential amino acid for human body. Its main biological function is to maintain the stability of membrane structure, regulate osmotic balance and inhibit lipid peroxidation of cell membrane. It is also an important cytoprotective agent. The increase of free radical production during exercise is closely related to the decrease of exercise ability. Free radicals make the biofilm of various organs in the body undergo lipid peroxidation. Taurine, as a sports nutritional supplement, can not only directly exert its antioxidant function, but also enhance the antioxidant capacity of the body by improving the activity of antioxidant enzyme system in the body, and protect the cell membrane from free radical attacks, thus enhancing the exercise capacity of the body. Taurine can effectively regulate Ca2+ homeostasis disorder caused by many reasons, and it is a good endogenous Ca2+ regulator. Lipid peroxidation, Ca2+ homeostasis disorder and energy metabolism disorder are closely related to biofilm damage during exercise fatigue, and taurine has a good effect on these processes.

Creatine is synthesized from arginine, glycine and methionine as precursors in liver, kidney and pancreas. The content of creatine in normal muscle is 120 ~ 125 mmol/kg dry weight muscle. Creatine and phosphocreatine constitute the human creatine pool, about 96% of which exists in skeletal muscle, and phosphocreatine in skeletal muscle accounts for 2/3 of the total creatine pool. The increase of creatine and creatine phosphate reserves is beneficial to maintain ATP level during high-intensity exercise and promote the biosynthesis of creatine phosphate during the interval of repeated high-intensity exercise. Short-term creatine supplementation can increase the maximum work and strength by 5% ~ 15%.

Creatine supplement method: the supplement dose should be strictly controlled according to the actual weight of athletes. The general impact dose is 20g per day for 5 ~ 7d. The maintenance dose is 2 ~ 5g per day, and it is best to supplement creatine and glucose at the same time, which can stimulate insulin secretion and increase the efficiency of creatine uptake by muscles. However, it should be noted that improper supplementation will cause two side effects: weight gain and muscle stiffness.