The term “muscle strain” (technical term: distension) is used in medical terminology to describe the process of stretching a muscle beyond the usual extent. The muscle strain as such must be distinguished from a torn muscle fibre. In the latter case, the smallest tears within the muscle fibers occur and an associated accumulation of fluid (edema). A pulled muscle, along with the torn muscle fibre and the torn muscle, is one of the most common muscle injuries that can occur during sport. Muscle strain is the easiest form of the three types.
Muscle strain is one of the most common injuries that occur in direct connection with sports activities. Almost every athlete is affected by this disease at least once (rather more often) in the course of his or her athletic career. Clinically, the muscle strain, together with the rupture of muscle and muscle fibre, is counted among the group of closed muscle injuries that do not affect the skin surface.
Basically, all people who do a lot of sports have an increased risk of developing a pulled muscle. Runners are particularly affected. In this group of patients, pulled muscles mostly occur in the calf and thigh muscles.
In contrast to most sports injuries, the mechanism by which a muscle strain develops is not based on external forces acting on the muscle tissue from outside (such as blows or kicks). The muscle strain is caused by excessive stretching of the affected muscle, which leads to a rapid and strong contraction of the individual muscle fibers. As a result, a hardening of the muscle tissue occurs within the muscle tissue.
However, the muscle fibers themselves are not affected. Typically, patients who suffer a muscle strain feel a sudden, cramping, violent pain. Permanent damage caused by pulled muscles can usually be excluded. However, to ensure a complete recovery of the affected muscle, it must be considered that any kind of sports activity should be stopped immediately after the occurrence of a muscle strain. Otherwise, there is a risk that an initially harmless muscle strain will develop into a torn muscle fibre over time.