Sports injuries are often caused by some kind of trauma to the tissue, for example, direct impact with the ground or another player. In other cases, tissue damage occurs when a joint is forced to move in a way that it is not physically capable of (for example, a sprain may be caused by rolling over on your ankle).
Injuries may also develop over a longer period, for example, due to over-use of particular muscles or joints. These types of injuries may be the result of using poor technique, or the ongoing use of inappropriate footwear or sporting equipment. For example, tendonitis of the elbow may due to a tennis racquet that is too heavy, or using an incorrect golf swing.
Stress fractures tend to be caused by running or jumping on hard surfaces, and most often affect the bones of the legs and feet.
Similarly, high impact activities such as running on concrete or other hard surfaces can contribute to the development of shin splints, as can over-training (e.g. training beyond your fitness level), wearing poorly fitting running shoes, running with poor technique, or having flat feet. The pain may be caused by the muscles and tendons of the leg causing inflammation by tugging on the bone, or may be due to a stress reaction from the bone itself.
Tendonitis is an inflammation of a tendon, a band of connective tissue that connects a bone and a muscle. It can be associated with a wide range of activities that put repetitive strain on the tendons, including sporting activities such as running, jumping, or lifting heavy weights. Tendonitis is more likely to occur if you don’t warm up properly prior to exercising, and being obese is also a risk factor, as it increases the amount of strain on the tendons.