"Marathon" and cardiovascular fitness – Sohu health Feng Xueyao, PLA No.306 Hospital, Department of Cardiology brand quality management office editor as everyone knows the amount of sports, influence on the human body almost all kinds of physiological structure and function of performance can be beneficial. Running is one of the most common sports activities that can improve cardiovascular endurance, while a marathon is a long distance run. For the first time as a sports event in the 1896 Olympic Games in Athens, Greece, the London Olympic Games in 1908 determined marathon distance of 42195 km. Today, marathon and long distance race not only attract the professional athletes all over the world, but also actively participate in the sports event. However, marathon and some long distance running for the general public, after all, is an extreme sport, its role in the cardiovascular dispute. In recent years, the occurrence of a sudden death in running events, analysis shows that most of these sudden death of cardiovascular death, then the long run in the end what the impact of cardiovascular disease? First, let’s get to the heart of the athletes". Henschen first proposed the concept of "athlete’s heart" in 1899. The athletes showed cardiac morphology of left and right ventricular enlargement, uniform wall thickening, heart weight index of left ventricle increased, cardiac output increased by 5~6 times, resting heart rate decreased. However, the formation of athlete’s heart needs long time, high strength endurance training. Marathon athletes usually need to maintain the heart within a few hours to maintain at 20~25L min, this exercise load for non professional sports enthusiasts is obviously a high intensity of stress. Cardiac structures, including coronary heart disease and cardiac conduction system, may be poorly adapted during this acute stress, leading to myocardial damage and fibrosis. A series of studies have shown that, after marathon runners, the myocardial injury markers of the runners are elevated, which is a reversible adaptive change. It is generally believed that endurance athletes are prone to merge with early electrophysiological changes, such as early morning and early chamber. These changes are considered to be functional and do not lead to malignant arrhythmia or sudden cardiac death. However, studies have shown that, at least in middle-aged male endurance athletes in the occurrence of atrial fibrillation was 5 times higher than the control group, the onset of paroxysmal, after may develop persistent atrial fibrillation. Marathon as a kind of extreme sports have certain risks. So what do we need to do before a long run? At present, in order to screen out the possible pathogenic factors of cardiovascular events should be carried out which medical examination is still controversial. The value of ECG in middle aged and elderly endurance athletes is generally recognized. It is recommended that exercise ECG should be performed in this population, especially for those with cardiovascular risk factors. The European Society for cardiovascular prevention and rehabilitation released recommendations for cardiovascular assessment in the middle and old aged population. Screening for large populations suggests the use of exercise habits and cardiovascular risk factors for self assessment, and for those who are at high risk for high intensity exercise.