Biochemistry of Muscle Contraction

The amount of lactic acid increases, and glycogen is used to form ATP, which is the main source of energy for the muscle. Phosphocreatine serves to quickly restore ATP from ADP (adenosine diphosphate), which allows muscles to receive energy faster.

The process of muscle contraction begins with the fact that a nerve impulse is transmitted from the brain to the muscle along nerve fibers. The impulse reaches the point where the nerve fiber contacts the muscle fiber and causes the release of the neurotransmitter acetylcholine, which binds to receptors on the surface of the muscle cell. This causes a change in the muscle cell film potential and leads to the release of calcium from special stores inside the cell.

Calcium binds to regulatory proteins, which leads to a change in the configuration of the myosin and actin proteins and causes their interaction. This interaction causes the muscle fiber to shorten and the muscle to contract. However, calcium also plays an important role in regulating muscle contraction, controlling the speed and force of contraction.

Since muscle contraction requires large amounts of ATP, the process of its formation is key in muscle biochemistry. ATP is produced in mitochondria, which are located inside the muscle cell. Glycolysis, which occurs in the cytoplasm of the cell, can also serve as a source of ATP, especially at low oxygen levels.

In addition, the lactate cycle plays an important role in muscle biochemistry, which allows the use of lactic acid, formed in muscles when there is a lack of oxygen, as an energy source, while restoring glucose. This process is called gluconeogenesis.

Thus, muscle contraction is a complex process that requires the participation of many biochemical and physiological processes. Despite the fact that the mechanisms of muscle contraction are not yet fully understood, modern research allows us to more deeply understand this process and use the knowledge gained to optimize training and treat many diseases associated with muscle dysfunction.