Human Athletic Ability and Performance

Abstract Genetic variation contributes to muscle function and endurance, both of which are essential qualities for success in athletics. For example, fast twitch skeletal muscle fibers are essential in sprinting while slow twitch fibers favor endurance. Genetic variants can determine the proportion of fiber type, in addition to other factors that contribute to endurance, the risks of injury, and the ability to repair damage. Some genetic variants are risk factors for conditions that predispose to sudden death. Cardiomyopathy, electrical disorders, and Marfan syndrome are examples. The most important screening measure is the family history. Routine electrocardiograms (EKGs) and echocardiograms could detect athletes most at risk for sudden death, but the cost-benefit varies among sports and the level of competition. A current controversy is whether genetic testing can predict to what sports a person, perhaps a child, should dedicate serious interest.