Generally, however, "stretching" refers to a method used to improve mobility. In this process, the muscle group being stretched is placed under tension by flexing or extending the adjacent joints. Among other distinctions, stretching can be divided into dynamic, static, active and passive forms, as well as various combined forms. None of these different forms of stretching has shown clear, scientifically proven advantages over the others.
Various types of stretching are a fixed component of athletic training and also play a role in rehabilitation. Certain sports require very good or even excessive flexibility, such as artistic gymnastics and rhythmic gymnastics. However, the positive effects that many athletes subjectively attribute to stretching or improved flexibility, such as on performance, recovery, or injury risk, have also not yet been clearly proven scientifically.