You must remember Forrest Gump from the movie: the ragged, bearded man on foot across America. From the East Coast to the West Coast, Gump ran tirelessly for three years, two months, 14 days and 16 hours, and then came to a screeching halt, running to the next part of his life. Forrest Gump’s legendary running life has inspired countless people. Off the screen, the real-life version of Forrest Gump has also been reported. In the United States, a man named Dean Kanas has been a long-distance runner for 16 years. He reportedly sleeps only four hours a day and spends almost all the rest of his time running. He has participated in countless marathons and endurance races all over the place, leaving his footprints on everything from roads to the world’s driest deserts, and he even runs thousands of miles home even after the race. By rough count, the total miles Mr. Dean Kanas has run is enough to circle the earth’s equator four times! Sports brought him strong muscles and sturdy bones. In our country, although there is no such Forrest Gump-style long-distance running maniac, long-distance running is also loved by many people as an economic and convenient means of fitness. The main potential hazard of long-distance running to the exercise system is the knee joint, and foreign countries even use “Running Knee” to name the patellofemoral joint pain brought about by incorrect exercise. It is especially important to protect the knee joint for those who run long distances with heavy exercise. Adopting proper posture from the start and strengthening the front and medial thigh muscles can be effective in preventing running knee. If the increased exercise makes you feel bad about your knee, stop and apply ice to the affected area to reduce your pain. In addition, the running site also has an impact on the knee joint, should try to avoid bumpy track, flat and comfortable plastic track is the best. Many running shoes now have shock-absorbing designs, which can also reduce knee injuries to some extent. In addition to the exercise system, the effect of long-term heavy training on the heart is also a topic of great interest. There is a consensus on the health benefits of moderate exercise, but it is unknown how years and years of intense endurance exercise affects the heart. Recent clinical observations suggest that endurance sports training may lead to arrhythmias (not arrhythmias during exercise, but presumably changes in the myocardial structure of the heart due to long-term endurance training, affecting the cardiac rhythm conduction system). In this regard, Spanish scientists designed and conducted experiments with rats: they divided male rats into two groups, one group was made to rest as a control, and the other group was made to run in a certain way for 4, 8 and 16 weeks, respectively. Finally, histological and biochemical methods were used to study the changes in the atria and ventricles of the rats in both groups. The results showed that by 16 weeks, the “overworked” rats had eccentric hypertrophy, dilated atria, reduced diastolic capacity, and significant signs of fibrosis in the ventricular muscles compared to the resting rats. Ventricular tachycardia was induced in 5 of the 12 overworked rats, compared with 1 of the controls. Those rats that rested after 8 weeks of exercise showed better myocardial fibrosis than those that continued to exercise. Therefore, the scholars concluded that in rats, prolonged heavy endurance training can lead to myocardial fibrosis and predispose to arrhythmias, according to the study published in last year’s Circulation. Since rats have a much shorter lifespan than humans, this 16-week “endurance training” in rats would be equivalent to more than a decade of continuous running in humans. Such a high level of exercise may only be achieved by some athletes who run marathons or long-distance races. A 2008 German study showed that older marathon runners showed more signs of cardiac fibrosis than older people of the same age group. But this study was challenged: some of the older marathoners in the report did not start the program at a young age, and some had a long history of smoking and other bad habits, so other factors could not be ruled out as causes of cardiac fibrosis. A few weeks ago, a similar study in the United Kingdom is more scientific: they selected some long-distance runners or rowers who had participated in the British national team or the Olympic Games as subjects, including some members of the “Marathon 100” club, these members have completed at least 100 marathons These members had completed at least 100 marathons and had received long-term endurance training during their athletic careers. Twelve of the study participants were 50 years old and older, while the other 17 were relatively young, ranging in age from 26 to 40 years. The study also recruited 20 physically fit, non-endurance athletes over the age of 50 as controls. Scientists performed MRIs on the hearts of these study subjects to assess their cardiac scarring or fibrosis. The results showed that half of the hearts in the older athletes group showed scarring, and these were the older athletes who had trained the longest and practiced the hardest that year; while no signs of cardiac fibrosis were found in the younger athletes and non-athlete controls. The researchers concluded that long-term, high-intensity endurance training does lead to cardiac fibrosis. The results of this study are consistent with those of animal models. From the above study, it is true that long-term heavy exercise endurance training is harmful to the heart, but we do not need to worry about it. For long-distance runners for fitness purposes, few people can train at the intensity of British national teams or Olympic athletes. But the American “real-life Forrest Gump” mentioned earlier in this article really needs to be checked out to assess the risk of cardiac fibrosis. For the individual, how to control the amount of exercise is a real problem, perhaps “run with the feeling” is really a good choice, I believe that Forrest Gump also does not have the strength to cross the United States at the beginning. The amount of exercise should be increased gradually, just enough to not cause discomfort. The benefits of sensible aerobic exercise far outweigh the risks associated with over-exercising. Recent studies have also found that aerobic exercise (endurance training) can benefit even people with heart disease. The adverse regulation of the heart’s autonomic nervous system that occurs as a result of disease can be reversed by proper exercise: aerobic exercise leads to moderate parasympathetic excitation of the heart, reducing the incidence of malignant arrhythmias (atrial fibrillation, ventricular fibrillation, etc.). Of course, the exercise of these special people needs to be carried out under the close supervision of medical personnel. Even heart patients are starting to exercise, lazy guys can not find a little excuse to avoid exercise. On the issue of exercise, if we can all have the same belief as Forrest Gump – of course not to run like him until the end of time – in life and health can only be a good thing. There should be a full warm-up before the start of a long run. Warm-up can make the body organs begin to adapt to the upcoming exercise, so that the body temperature rises, the heart rate begins to accelerate, the leg muscles vasodilate to bring sufficient oxygen. Warm-up should last about 10 minutes or more, so that the heart rate reaches about 70% of the maximum heart rate (maximum heart rate is equal to about 220 – age), if the temperature is very high, you can also reduce the warm-up time. If you feel tightness in a part of the body during the warm-up, you can stop and stretch accordingly to increase tissue flexibility and avoid injury during exercise.