It is not good for a person to exercise until his muscles ache every day. Scientific physical exercise needs to pay attention to the following problems, so as not to hurt your body instead of getting exercise. First, grasp the degree of load. When doing strength exercises, you should choose the appropriate load according to your actual situation, but no matter what kind of load you choose, you should follow the principle of growing from small to large, and don't suddenly increase the exercise load to cause sports injuries. Second, pay attention to the speed of action. As long as dynamic muscle strength exercises are carried out, there is a problem of movement speed, and load is closely related to speed. The greater the load, the smaller the speed. Exercisers should make reasonable arrangements according to the practice requirements. For teenagers, explosive power is very important. In strength training, it is very beneficial to choose appropriate load and speed up the movement as much as possible to improve the explosive force of muscles. Third, control the amount of exercise. For ordinary physical exercisers, it is not necessary to carry out strength training every day. Even for the purpose of developing muscle strength, adopting strength training every other day is enough to achieve the ideal effect. If you do strength exercises every day, not only the effect of improving muscle strength is not obvious, but also the development of overall function is not coordinated. Besides, physical exercise should also follow some basic principles. Although the physical exercise method is simple and easy to learn, we must pay attention to these principles if we want to arrange physical exercise scientifically, improve the exercise effect and avoid injury. (1) Principle of gradual progress: The gradual progress of physical exercise refers to the gradual progress from small to large, from easy to difficult and from simple to complex when learning sports skills and arranging exercise amount. (2) The principle of all-round development: In physical exercise, we should pay attention to the diversity of activities and the overall improvement of physical function. (3) Principle of differentiated treatment: When exercising, we should treat each exerciser differently according to his age, gender, hobbies, physical condition, professional characteristics and exercise basis, so as to make the exercise more targeted. (4) Principle of regularity: Only by participating in sports activities regularly can the effect of exercise be obvious and lasting, so physical exercise should be regular, and you can't fish for three days and dry the net for two days. Although short-term exercise will also have a certain impact on physical function, once physical exercise is stopped, this good effect will soon disappear. (5) Safety principle: Pay attention to safety in any form of physical exercise. If the physical exercise arrangement is unreasonable and violates scientific laws, injury accidents may occur. People who go in and out of the gym pay attention to the essentials. Now, fitness has become a fashion. Many people choose the gym, but not all fitness methods are beneficial and harmless. Some fitness experts have pointed out some "essentials" for us, which have good reference significance for our scientific fitness: do necessary warm-up: muscles are easier to be controlled and expanded when relaxed, and doing these exercises will reduce your chances of injury. Therefore, it is best to spend 5 minutes to get your body fully active and feel a little sweaty. This step is a good start for fitness. Do necessary stretching exercises: There are always some things in life that are very easy to do, but stretching after fitness exercises is not so simple. When you exercise your muscles, they become tense and shortened. Stretching is to help you relax your muscles, so as to prevent muscle soreness the next day. The best time to do this action is after the warm-up exercise, and it must last for 20 ~ 30 seconds, which will help the muscles relax and let the bodybuilders get more meaningful stretching exercises. Don't do heavy lifting: you need to start slowly in the gym and increase your exercise step by step. Because you may not imagine what kind of pain you will have within 24-48 hours after exercise, you need to be careful from the beginning. In addition, if you blindly try to lift more than your body load, it may lead to muscle strain, sprain and even back injury. From this point of view, it is more appropriate to choose a weight of 3-6 kg. Repeat the action at ordinary times 15 ~ 20 times. If you want to get strong muscles faster, you can also choose a slightly heavier weight, but repeat it 8 ~ 12 times. Don't rush for success. Only by completing exercises in moderation can you achieve good results. Don't exercise too much: Since the purpose of fitness is to persist in the future, it doesn't mean that you must exercise too much. Because once you feel that exercise brings discomfort to your body, it is often difficult to stick to it. If you feel that you are in poor health, you can choose some easier exercises to complete. It is also a good way for people who don't want to go to the gym to choose suitable aerobics CDs, learn the basics and improve the coordination of movements. Make necessary water supplement: When you are exercising, your body will lose water quickly because of sweating, and these liquids must be replenished in time. Otherwise, over time, people will be dehydrated and feel thirsty. So, don't forget to hydrate your body from beginning to end. Generally speaking, the human body needs 8 breasts of water every day, and needs more when it starts to exercise. Besides, plenty of water helps to reduce hunger and appetite. Don't rely on mountaineering equipment: sometimes people feel very tired, but the effect of exercise is not as good as expected, but they still hope to get more benefits through exercise. So I desperately "ran" on the mountaineer until my body couldn't bear it. However, this kind of "passive" exercise-relying on the climber to chase and complete the task, will only do harm to the body, but will not achieve the purpose of exercise. At this time, the climber is only a tool to help joint mechanical movement, not an exercise helper. Therefore, it is very important for everyone to choose reasonable exercise intensity and correct methods for themselves, rather than "passive methods" that keep the body in a passive state. Gradually increase the intensity of exercise: high-intensity exercise is not suitable for the beginning of fitness training, but it is worth noting for people who have been practicing for 6 months or more. After reaching a certain level, you usually enter a state of stagnation, and most people may think that "I don't see any changes in my body"-so they will speed up their pace and create a bigger challenge for themselves: increase exercise to achieve the effect of changing my body. However, at this time, your urgent mood makes you fall into a misunderstanding. The increase of exercise intensity needs to be gradual, and it is best to gradually improve the duration and degree of exercise. You can extend it from 20 minutes to 30 minutes, and change your 5 kg dumbbell into 8 kg dumbbell. It just doesn't have to be done overnight, and time and intensity can be chosen. Don't be too hasty in exercise frequency: some people insist on practicing in order to speed up the exercise frequency in the gym, regardless of their physical reactions. Especially for sports like weightlifting, if you do it too fast, strenuous exercise will overload your muscles and make them fragile. So, here is a simple rule: 2 seconds to lift, 4 seconds to put down, you have to keep moving up and down rhythmically. The slower you do it, the better you will be. Don't eat or drink water during exercise: any exercise lasting less than 2 hours doesn't require you to replenish your physical strength, so it is enough to ensure that you eat within 1 hour before exercise. Sports drinks are harmless to the body, but they are still not as beneficial as pure water. Besides, a diet with high alcohol content is futile for exercise. After the exercise, you need the necessary "cooling": just as the body needs time to "warm up" before fitness, it also needs time to restore calm and let the heart rate return to normal after exercise. Slow down slowly until the heartbeat returns to below 120 beats per minute. When you feel that your heartbeat tends to ease and your breathing is gradually stable, you have completed the final "cooling down" work. In life, many people choose to run in the morning, but not all of them are beneficial and harmless. The key depends on the environment during exercise. If you run in the dense fog in the morning, strenuous exercise will increase the air intake. Moreover, due to the high water vapor content in the fog, various pollutants suspended in the air are not easy to spread, and once these pollutants are inhaled excessively, they will cause great harm to the body.