Your foot will naturally supinate and pronate, or rotate in and out, as you run. However, excessive supination or pronation raises your risk for overuse injuries associated with running, such as stress fractures and tendonitis. Too much foot movement when you run can have a variety of causes. The best way to pinpoint the cause of your issue is to visit a health care provider for a gait analysis.
Common Overpronation Issues
Your foot naturally pronates when you make contact with the ground. You are an overpronator if your foot moves inward too much or if it is still moving inward when it ought to be moving outward. If you have flat feet, meaning low arches, you have a high risk for overpronation. Wearing shoes that do not work with your body's biomechanics or wearing shoes that are excessively worn raises that risk.
Other Overpronation Causes
Though flat feet is most frequently mentioned as a risk factor for overpronation, other issues can cause you to move your foot inward too much. Lack of motion in your ankle joint is one possible cause. Bow legs, a short calf muscle or Achilles tendon, a short hamstring, a short iliopsoas muscle and limb length discrepancies also lead to overpronation.
Supination
Supination naturally occurs as your foot prepares to leave the ground. You supinate too much if your foot moves outward when it should be pronating instead, or when it moves outward too much. An extremely high arch raises your risk for supination. A second metatarsal bone that is abnormally positioned also may lead to supination. Your metatarsal bones are the long bones in your forefoot. Excessive supination is much less common than overpronation.
Significance
Biomechanical faults in your feet or legs that cause overpronation or abnormal supination lead to a situation in which too much force is placed on one area of the foot. When you run, the force is equal to three times your body weight. Continuously placing too much force on one area of the foot is likely to lead to injury. It also eventually may lead to osteoarthritis, writes "The Good Foot Book" author Glenn Copeland. Special shoe inserts, called orthotics, help correct abnormal foot alignment and motion, thus reducing your risk for a foot injury. Visit a health care professional to ensure you get the correct prescription and are wearing footwear that will improve your gait, not hinder it.
