transfer to cytochrome c. Complex III is embedded in the inner membrane of the mitochondria and consists of 11 subunits. Cytochrome b is encoded by the mitochondrial DNA which differs from all other subunits which are encoded in the nucleus. Cytochrome b plays a major part in the correct fabrication and function of complex III. This mutation occurred in an 18-year-old man who had experienced exercise intolerance for most of his adolescence. Symptoms included extreme fatigue, nausea, a decline in physical activity ability and myalgia. Intracranial hypertension Individuals with elevated levels of cerebrospinal fluid can experience increased head pain, throbbing, pulsatile tinnitus, nausea and vomiting, faintness and weakness and even loss of consciousness after exercise or exertion. General physical problems A person who is not physically fit due to a sedentary lifestyle may find that vigorous exercise is unpleasant. Diagnosis Objective tests for exercise intolerance normally involve performing some exercise. Common tests include stair climbing, walking for six minutes, a shuttle-walk test, a cardiac stress test, and the cardiopulmonary exercise test (CPET). In the six-minute walk test, the goal is to see how far the person can walk, with approximately 600 meters being a reasonable outcome for an average person without exercise intolerance. The CPET test measures exercise capacity and help determine whether the cause of exercise intolerance is due to heart disease or to other causes. People who experience significant fatigue before reaching the anaerobic threshold usually have a non-cardiac cause for exercise intolerance. Additionally, testing for exercise-induced asthma may be appropriate. Treatment Exercise is key for many people with heart disease or back pain, and a variety of specific exercise techniques are available for both groups. In individuals with heart failure and normal EF (ejection fraction), including aortic distensibility, blood pressure, LV diastolic compliance and skeletal muscle function, aerobic exercise has the potential to improve exercise tolerance. A variety of pharmacological interventions such as verapamil, enalapril, angiotensin receptor antagonism, and aldosterone antagonism could potentially improve exercise tolerance in these individuals as well. Research on individuals with Chronic obstructive pulmonary disease (COPD), has found a number of effective therapies in relation to exercise intolerance. These include: Oxygen supplementation Reduces carotid body drive and slows respiration at a given level of exercise. Treatment with bronchodilators Clinically useful improvements in expiratory airflow, allows fuller exhalation in a given period of time, reduces dynamic hyperinflation, and prolongs exercise tolerance. Heliox (79% helium,