The muscle fiber structure consists of two parts. 1-myofibril,2 connective tissue. Myofibril is the contractile and excitable fiber of the muscle. The connective tissue acts as the roof of the hanger, holding the muscle fibers, vessels and nerve bundles together.

Most of the tissues in the musculoskeletal system heal by forming scar tissue. Most of the healed tissue leaves some scar tissue and cannot be restored. The repair process and amount of tissue vary according to the type, severity and region of injury.

The repair phase is examined in 3 parts.

Destruction phase: When the muscle fiber is injured, a problem occurs in the cross-sectional area of the entire myofibril. Without adequate treatment, the scarred area of the muscle fiber enlarges. In the first phase of the muscle, there is a contraction band mechanism developed to protect the muscle and prevent the problem from spreading to other myofibrils. It occurs a few hours after injury and prevents macrophages from destroying tissue and plasma membranes. Meanwhile, plasma membrane repair continues. It is characterized by the destruction and removal of destroyed tissues after the accumulation of hematomas between myofibrils. Also, phagocytosis is performed by macrophages to prevent further enlargement of the necrotic area.

Day 2: Necrosed and injured myofibrils are phagocytosed. In addition, the tissues formed by fibroblasts begin to come towards the center of the injured area. 3rd day: Satellite cells (satellite cells) are activated and begin to form myoblasts in the repair area.

Repair phase: It aims to create scar tissue and myofibril in the tissue. 5th day: Myoblasts begin to scar in the central region by uniting in the regeneration area. 7th day: Cells that provide regeneration begin to spread towards the center. Old basal laminae are decentralized. 14th day: The scar tissue formed by fibroblasts in the center begins to get smaller and smaller. 21st day: Myofibrils begin to fuse as they go to the central region.

Remodeling phase: (3 weeks-1 year): It aims to increase the number of active contractile muscle fibers by increasing the functional capacity, reorganization and getting close to the old state.

* It starts with immobilization. It should be kept for less than 1 week. this time is sufficient for the scar tissue produced to keep the center stable and as a single unit and for the formation of satellite cells.
* Muscle injury is the type of injury that causes the most time loss among sports injuries.
* Stretching is avoided for the first 7 days. however, the binding of myotubules to each other was found to be tighter in people who had immobilization for a short time compared to the immobilization group.
* After the 6th hour after injury, necrotic events, atrophy and destruction begin.
* Since myofibrils and vascularization are more in athletes, ecchymosis and discoloration are more common.