(A) take the initiative to find more opportunities for in-kind expenditure.

Although in the development of modern society, people's physical labor is decreasing, it is a trend to increase mental labor. But as an individual in society, everyone can flexibly spend more on his body in life. For teenagers, help parents do more housework, such as washing dishes and washing clothes, reducing the use of dishwashers and washing machines, going to and from school to ride bicycles instead of cars, and not taking the elevator upstairs and downstairs in an emergency.

(2) Long-term mental work should be interspersed with appropriate sports activities.

Due to continuous study at their desks and surfing the Internet, many teenagers spend too much time sitting still every day, which hinders people's blood circulation. At the same time, brain cells are in a state of continuous high tension and activity, and the brain is in a state of high load for a long time. If it is not properly regulated, it will easily have adverse effects on the nervous system.

Therefore, it is necessary to insert some physical activities into long-term mental work. For example, when you study at your desk and surf the Internet for more than 1 hour, you should stop to do gymnastics, exercise stiff limbs and joints, and let your brain rest and adjust. However, if you surf the Internet indoors in a closed space, besides intermittent sports activities, you should always pay attention to breathing fresh air outdoors to reduce the impact on human health caused by long-term exposure to polluted air environment.

() Fitness exercise is a means of active rest.

Whether after physical or mental work, proper participation in sports is conducive to eliminating fatigue.

Someone has done such an experiment. One way is to shake things with your right hand first, and then shake them with your left hand when your right hand is tired. So the fatigue of the right hand will soon disappear. Another way is to shake things with your right hand first, and then let your hands rest when your right hand is tired. The result of the test is that the fatigue of the right hand slowly disappears. Medically, the law of this action is called cerebral cortex induction. The commonly used inductive rules are: upper limb fatigue, lower limb fatigue, upper limb fatigue, brain and eye fatigue, doing gymnastics and so on. These can reduce fatigue. And this active way of rest is more conducive to health.

Another study also shows that people do some relaxing exercises after work and study, and the recovery of physical fatigue is better than sitting or lying still. This is because the positions of the nerve centers (cerebral cortex) that dominate labor and sports activities are different. Physical activities after study and work can deepen the inhibition of the nerve center that commands labor activities, and make the muscles involved in labor activities fully relax and rest;

On the other hand, physical activities stimulate the human respiratory and circulatory system, accelerate blood circulation, accelerate and deepen breathing, improve oxygen supply to muscles, accelerate the metabolism of nutrients and promote the discharge of metabolites. In terms of short-term effect, physical exercise helps to eliminate fatigue. As far as the long-term effect is concerned, physical exercise can improve physical fitness, thus improving the efficiency of study and work.

Teenagers who undertake a lot of mental activities should take part in some sports activities according to local conditions. These activities can make teenagers' nervous brains have a better rest, and can also exercise their muscles that are rarely active at ordinary times, so that their physical functions can be maintained and developed.

() Take physical exercise as an indispensable part of life.

There is a law in biology, the user enters, and the waste is out. In the information age, people's muscles, limbs and internal organs no longer need to bear high-load physical labor. But if the body really degenerates, it is not good news for everyone. Because people need strong physical support to walk upright, adapt to the fast-paced information-based social life and maintain a healthy body. Therefore, less physical labor does not mean that the motor function of the human body can be weakened. Therefore, physical exercise should be regarded as an indispensable part of daily life in the information age.

How to make physical exercise a daily natural habit is very difficult for many teenagers. Of course, people have their inherent inertia. However, we can experience the psychological process of habit formation through examples of people developing the habit of brushing their teeth. First of all, many children don't like to brush their teeth at first, but when there is tooth decay, their parents will always urge them to brush their teeth. They must have been unwilling or perfunctory at first; With the growth of age, the experience of toothache makes them dare not neglect brushing their teeth all day; When the habit is formed, some people forget to brush their teeth before going to bed, so they may not be able to sleep alone.

Because brushing your teeth has become his unshakable habit at this time, it will be very uncomfortable if you don't do it for a day. This is the process of habit formation. It is difficult for some teenagers to get into the habit of physical exercise because they don't have enough awareness of fitness, and they don't have the severe pain like dental diseases to stimulate their awareness of self-protection. However, the influence of long-term lack of physical activity on the body will appear as time goes by, and its power is no less than toothache. It is a truth that every wise teenager should realize as soon as possible to form the habit of physical exercise before he is "sick" and "weak".