Bradycardia is the medical term for a heartbeat which is too slow or has symptomatic pauses. For well-trained athletes, bradycardia at rest may be normal. For most people, however, bradycardia may indicate the presence of a serious heart rhythm disorder. Due to bradycardia the heart may be unable to pump sufficient blood into the body. To supply the body with sufficient oxygen-rich blood to meet metabolic demand, the beat rate of a healthy heart increases automatically upon exertion and during exercise, for example, but also in response to acute mental stress, which may be caused by strong emotions and psychological states. In patients with chronotropic incompetence, however, the heart fails to respond, resulting in a heart rate which is too low to meet the body’s needs.