Zhou Tong, master of sports medicine and attending physician of Guangzhou National Fitness Guidance Center, said that long-distance running is an aerobic endurance exercise, which has a positive effect on improving cardiopulmonary function and physical health. For the general population, moderate-intensity jogging is recommended, and the exercise time is gradually extended and the speed is gradually accelerated. Some people who don't exercise often or are new to long-distance running may have some doubts about this sport: will running make their legs thicker? Why do I always feel out of breath when I run? Sports experts from Guangzhou National Physical Fitness Monitoring Center are here to answer one by one. 1 What are the benefits of long-distance running? Xiao Yan will be 25 years old next month. On this day, my friend said half jokingly and half seriously, "When a woman is over 25 years old, her metabolism will slow down. There is a park near your home, but you have been doing nothing, wasting such a good geographical position. Simply take a few nights a week to run. " After listening to a friend's reminder, Xiaoyan asked, "What are the benefits of running?" Expert's explanation: Zhou Tong introduced that scientific experiments have confirmed that long-distance rhythmic deep breathing can make people inhale a lot of oxygen. When the oxygen intake is more than 7~8 times of normal, the vital capacity will increase accordingly; Long-distance running can also improve the oxygen supply state of myocardium, thicken myocardial fibers and enhance myocardial contractility, thus improving the working ability of the heart, so long-distance running is a very good way of fitness exercise. Moreover, in the process of long-distance running, the blood circulation in the human body is accelerated, and the harmful substances in the excretory system are cleaned up, thus making it difficult for harmful substances to stay and spread in the body. According to the measurement, when you run 3000m in 16 minutes or 5000m in 25 minutes, your blood cholesterol level will drop. Long-distance running is not only for fitness, but also for "heart". Because we don't care about the outcome of the competition, we just want to exercise in a relaxed and happy way, so it can best promote the release of endorphin bark, a polypeptide substance in the body, thus making people have lasting euphoria and sedation, which is very beneficial to alleviating the mental and psychological tension brought about by high-tempo and high-intensity exercise in modern society, and also has a good effect on cultivating people's tenacious will to overcome difficulties and temper their fighting spirit. However, Zhou Tong warned that people who are not used to physical exercise at ordinary times should do it step by step. If the amount of exercise greatly exceeds the usual load, it may lead to sudden death or other sports injuries; Those who suffer from chest tightness, headache, dizziness, cardiovascular and cerebrovascular diseases due to mild activities should consult a doctor before starting exercise. In addition, before starting long-distance running, we should make full preparations for sports and ensure good road conditions. Question 2: Does running make your legs thicker? Just when Xiaoyan was tempted, she suddenly remembered that she had seen the saying that "running will make people's legs thicker" on the online women's forum, and she couldn't help worrying that running would run out of the legendary "elephant leg". Experts dispel doubts: For women like Xiaoyan who don't aim at "training big cats", the fear of "running more and more errands" is understandable. However, Zhou Tong pointed out that whether running can thicken your legs depends on how you run. Proper running will not only make your legs thicker, but also lose weight. "If you don't believe me, just look at the figure and lower limbs of long-distance runners." Zhou Tong said that for most people, the real culprit of thick thighs is fat. But how to judge? "When the legs are not hard, all the hands can pick up are fat." In general, it is much easier to lose fat than gain muscle. After a period of effective fat-reducing exercise, in most cases, the muscles do become stronger and tighter, but the girth of the legs will become smaller. General jogging, relaxing running and long-distance running without competition are all moderate exercises, which will make these fats disappear and have a small degree of muscle development, so these kinds of running will not only make the legs thicker, but also have the effect of stovepipe. Sports with relatively gentle strength also include: riding a bicycle, skipping rope easily, swimming and so on. On the contrary, the intensity of running and strength exercises is relatively high, which can increase muscle volume and thicken legs. In fact, women need very little hormone secretion to synthesize muscles, and it is difficult to form muscles even if they exercise a lot. And the contribution of normal diet to muscle growth is very limited. However, all muscles that exercise can absorb nutrients more easily than those that have not been used for a long time, and exercise can also relatively improve the level of growth hormone. Exactly whether everyone will thicken their legs during exercise depends on the specific situation. For example, everyone's genetic situation is different, and it is not excluded that running will make a very small number of women's lower limbs thicker. There is a saying on the Internet that leg press and stretching before and after running can prevent the lower limbs from getting thicker. In this regard, Zhou Tong said: "There is no relevant theoretical basis for this statement, but these are all relaxation activities that should be done before and after running, which is conducive to preventing injuries and accelerating physical recovery. Relaxation and massage after exercise can also accelerate the release of fatigue and the removal of metabolites. " Doubt 3 Why is running always "not enough"? After eliminating the worries in his heart, Xiao Yan began to jog. But not long after, she found a new problem: I thought that every vital capacity test was "excellent" when I was in college. Why do you feel "out of breath" without running a few steps now? It's only been a year or two since graduation. It's impossible to "degenerate" so quickly, right? Expert explanation: Zhou Tong explained that people who don't exercise regularly or for the first time like Xiao Yan often have the phenomenon that "running a few steps is not enough" in long-distance running. But "Qi deficiency" is not only related to vital capacity, but also related to heart function and muscle adaptability. Generally, running for the purpose of fitness is long-term jogging, and there is a process of gradual adaptation. People who don't exercise often or run fast are particularly prone to feel "out of breath" Zhou Tong explained that this is actually due to the lack of exercise, the weak reserve and adaptability of the heart, and the low reserve and metabolism of energy of the muscles, which cannot meet the needs of physical exercise. Xiao Yan's lung capacity is excellent, but he still feels out of breath when running, which may be the reason. It is better to exercise more than three times a week. If you already have a good sports foundation, you are still panting when running, which may be a sign of excessive exercise intensity. He said that when jogging, you should keep your heart rate at 120~ 140 times per minute. "The specific feeling is that you can talk to your partner effortlessly while running-you must be out of breath. At the beginning of exercise, the recommended intensity was even lower than this. " If you feel tired after exercise, but you are in a good mental state, full of physical strength, eat well and sleep well, it means that the amount of exercise is appropriate. He also reminded that under moderate exercise intensity, each exercise time is 30~60 minutes. If you can't reach this exercise time from the beginning, there is no need to persist, let alone rush for success. You can wait for a period of exercise and then gradually increase the amount of exercise. But it is best not to "compromise" the exercise frequency, and it is better to keep it at least three times a week.