2. The principle of step by step, whether it is strength, speed or movement difficulty, should be step by step in the training process. Only in the state of low difficulty, low load and low speed can we be foolproof, and then try faster, heavier and more difficult training.
3, the principle of repetition, the human body is undergoing metabolism all the time, muscles, ligaments, bones, blood circulation, nerve conduction, energy supply and other systems are an organic and constantly changing whole.
As long as we relax a little, our bodies will go into a rest state like a car at idle speed. If we do this for a long time, our bodies will be like cars. Not only will the engine accumulate carbon, but even the gearbox, heat dissipation, brakes, air conditioning and other systems will fail due to lack of exercise.
Practice instructions
First, avoid exercising under strong light.
Around noon, the hot sun is in the sky and the temperature is the highest. In addition to swimming, avoid exercise at this time and beware of heatstroke. In summer, the ultraviolet rays in the sun are particularly strong, and human skin can be burned by I ~ II after long-term exposure. Ultraviolet rays can also penetrate the skin and bones, radiate to the meninges and retina, and cause damage to the brain and eyeballs.
Second, avoid too long exercise time.
An exercise time should not be too long, generally 20 ~ 30 minutes is appropriate, so as to avoid excessive sweating and high body temperature, which may cause heatstroke. If you exercise for a long time, you can arrange 1 ~ 2 breaks in between.
Third, avoid drinking plenty of water after exercise.
A lot of exercise and sweating in summer, so drinking a lot of water will increase the burden on the blood circulation system, digestive system, and especially the heart. At the same time, drinking water will make you sweat more and further lose salt.
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