Exercise may not be a hobby, but it is a need, an underlying and easily ignored need. Exercise is valuable, but health is more expensive. Exercise is often considered a personal hobby, but I would argue that exercise is more of a need, a life need for your health. Peak oxygen consumption is the best indicator of cardiorespiratory adaptability and exercise capacity. Numerous studies have shown that the level of peak oxygen consumption is a strong predictor of death, and for every 1 metabolic equivalent (MET) increase in peak oxygen consumption, the probability of survival increases by 10% to 25%; its maximum value occurs between the ages of 15 and 30. Thereafter, peak oxygen consumption decreases progressively with age. Increasing or maintaining one’s peak oxygen consumption can reduce the risk of death, whether from cardiovascular disease or malignancy. What makes exercise healthy? You can’t add today’s temperature to yesterday’s, so that tomorrow will be a warm spring day” – Qian Zhongshu, “The Siege”. Exercise is also a necessity for health, and a declining body is bound to decline progressively if it is not activated by exercise of sufficient intensity. Simply put, the existing medical exercise guidelines for healthy people are: ① moderate intensity exercise, a single 10-30 minutes, a total of 150 minutes per week; ② high intensity exercise, a single at least 20 minutes, a total of 75 minutes per week; ③ a combination of the two, the total amount of equal can be. Relatively easy to control is the single exercise time and the number of exercises, how to judge and control the intensity of exercise, is the basic principle and important factor of safe and effective exercise exercise. Unfortunately, the current science websites or magazines for this very professional content can only make a simple introduction. Theoretically, a strict intensity judgment requires direct determination of peak oxygen consumption, which is an impossible task for the majority of people; however, we can first approximate it through a simple formula. First, the individual’s peak heart rate (220-age) is derived from age; second, exercise that maintains a heart rate of 70% to 85% of peak heart rate is called moderate intensity exercise, and exercise that maintains a heart rate of 85% to 95% of peak heart rate is called high intensity exercise; finally, it must be understood that there are differences in peak heart rate between individuals, and this is the complexity of medicine, as my personal exercise experience My personal exercise experience is an example. After exercising for 10 months at the formula-derived peak heart rate (220-42=178bpm), I performed a standard symptom-limited exercise panel test to clarify my personal peak heart rate, which showed a peak heart rate of 192bpm, 14bpm more than the formula-derived value of 178bpm, thus showing the error of the formula. Thereafter, it is more accurate to extrapolate the exercise intensity based on the measured peak heart rate. Therefore, if conditions permit, it is recommended to perform an exercise plateau test after a period of sustained exercise, which can more accurately determine the intensity of exercise and can also help you determine the risks and benefits. Are you exercising in a reasonable manner? Exercise and exercise is a double-edged sword. For people who are not very active, exercise and exercise are encouraged; however, for people who exercise frequently, they need to be wary of exercising too much because, there is also a middle ground for exercise and exercise. As early as 1986, among male alumni of Harvard University, the risk of death was found to be associated with exercise energy expenditure, decreasing gradually from <500 kcal per week to 3500 kcal per week, and increasing slightly above 3500 kcal, but still lower than those <500 kcal. Recent results from large-scale exercise studies suggest a 30% reduction in the risk of death in runners compared to non-runners, in other words, a 3-year increase in life expectancy. Most notably, the most substantial cardiovascular benefit came from moderate exercise workouts rather than extreme exercise. While the development of marathons has prompted more people to participate in exercise, unfortunately, there are no studies looking in detail at the benefits for marathon runners - do we need that many marathon runners? What we need is a healthy body, let safe and effective exercise help you achieve it. It is well established that the level of cardiorespiratory fitness/peak oxygen consumption is more protective of your cardiovascular system than overall physical activity level, which is why high-intensity exercise is more beneficial than low-intensity exercise. From a benefit perspective, the higher the intensity the greater the rate of benefit from exercise; from a safety perspective, the lower the intensity the safer the exercise. The two go against each other, and it is probably best to be near the intersection of the two curves, because we want to be both safe and effective. Each person should personalize the choice of their own exercise intensity according to their own ability and time. People with high ability and little time can choose the greatest possible exercise intensity within the safe range, which can produce significant results with a short exercise workout, especially for healthy white-collar people who need high efficiency. Weak ability and more time can choose medium intensity, on the basis of safety is fully guaranteed to extend the exercise time, gradually benefit, especially suitable for sub-healthy people. There are two other scenarios other than medium to high intensity: too low and too high. In healthy people, from a professional point of view, the intensity of exercise under the guidance of pedometer is too low, not reaching the lower limit of medium intensity, and the improvement of physical quality is slight, so it is recommended to give up, but it is still beneficial to obese people. Too high, beyond 95% of the peak heart rate of the intensity of exercise has considerable risk, such as unsupervised do not recommend trying, marathon runners may be related to the accident occurred during the race. "Some people exercise regularly and punch a clock. To be honest, the available research shows that there is a ceiling on the effects of exercise, not an unlimited improvement by extending the time or increasing the number of times. The greatest magnitude of exercise benefit comes from sedentary people moving around, simply put, from 0 to 1. The process from 1 to 2 or even 9 can still benefit, but the magnitude becomes significantly smaller. Significantly longer single exercise sessions and total exercise time will significantly reduce the payoff/benefit ratio, with appropriate choices and adequate rest to avoid exercise addiction and injury. The choice of exercise is another important factor that affects the benefit. Strength and endurance are the choices that sports enthusiasts need to go up against in their workouts. Many fitness websites or organizations always come up with muscular men to encourage fitness, but from a professional point of view, it's not. A study of Finnish male world-class athletes found that strength athletes can extend their life expectancy by 1.6 years, while endurance athletes can extend their life expectancy by 5.7 years. Thus numerous sports guides recommend strength training as an adjunct component to endurance training. 10,000m champions are less famous than 100m champions, but benefit more. I think that for the average person, showing off muscle mass is a disguised discouragement to exercise, and not many people who are motivated to exercise will stick with it, and even if they do, the benefits are limited. Of course, strength training is a necessity, and there are still many times when you need a little strength in your daily life, and not having it in your hands can significantly reduce your quality of life. The world is a big place, just in case you want to put your backpack on and go far away someday!