Common causes of overuse injury. An overuse injury is any type of muscle or joint injury, such as tendinitis or a stress fracture, that's caused by repetitive trauma. An overuse injury typically stems from: 1  Training errors. 2  Training errors can occur when you enthusiastically take on too much physical activity too quickly. 3  Going too fast, exercising for too long or simply doing too much of one type of activity can strain your muscles and lead to an overuse injury. 4  Technique errors.