An overuse injury is usually caused by repetitive activities over a period of time. It is often due to excessive and repetitive loading of the specific tissue with a gradual onset of symptoms. During the early stages of the injury, there is little or no pain and the athlete might unknowingly continue to place pressure on the injured area. As a result, the area does not have the necessary time to heal. The cause of an overuse injury is often less obvious, compared to the macro-trauma of an acute injury. The principle in overuse injury is that the repetitive microtrauma overloads the capacity of the tissue to repair itself. During exercise, the various tissues such as muscles, tendons, bones and ligaments, are being loaded and experience excessive physiological stress. After the specific exercise activity, the tissues undergo adaptation in order to strengthen and to be able to withstand similar stress in the future. If the adaptive capability of a specific tissue type is exceeded and injury occurs, this is most often an overuse injury. Therefore, in overzealous athletes, that do not allow adequate time for adaptation to occur before the next workout or training session, the cumulative tissue damage eventually exceeds the threshold that the tissue can handle and this causes pain and dysfunction.