From the point of view of fitness, fitness is a lifetime thing, not a certain period of time. People who really understand fitness no longer regard fitness as fitness. Fitness has become a part of daily life, just like washing your face and brushing your teeth after getting up every morning, and even as important as eating every day. However, today's article is not about the importance and habituation of fitness, but about whether not exercising muscles for a long time will decrease. From birth to death, human muscles are constantly changing. From childhood to adulthood, human muscles are constantly growing, but from adulthood to old age, human muscles are constantly shrinking and decreasing, which is a normal physiological and biochemical function of the human body. It can be said that with the growth of age, a person's muscles from less to more, and then from more to less. As for whether not exercising muscles for a long time will decrease, we can analyze it like this. Through exercise, a person can first improve the body's muscle mass and increase the body's muscle mass. At this time, the muscles of the body are growing in quality and quantity. If a person doesn't exercise for a long time, the muscle quality will first decline, which is mainly reflected in the fact that muscle strength and endurance are not as good as exercise. If you don't get exercise, your muscles will start to shrink and the number of muscles will decrease. Therefore, if a person does not exercise for a long time, his muscles will decrease. Exercise can not only improve muscle mass and increase muscle mass, but also delay muscle atrophy caused by age. Finally, when it comes to fitness, some people will say that they are busy and have no time to exercise. Some people will say that there is no professional fitness equipment, no way to exercise and so on. In fact, these are all self-deception. You can exercise anytime. Fitness exercise is not as complicated as many people think, and it does not need professional fitness equipment, special fitness venues or enough exercise time. You just need to run 10 minutes, do push-ups, do squats with your bare hands and so on. And do it every day. Fitness is persistence. If you don't want to lose your muscle mass or your muscle mass, please keep exercising every day!