I have been learning to swim for two years. From the first time I got into the water, I fell in love with this sport. I like the feeling of relaxing and floating in the water, like the feeling of water droplets slipping through my body, and like the warm sunshine on the shore after swimming. Swimming makes me like sports more and love life more.

I first came into contact with swimming with the idea of exercising. I used to be in poor health and often got acne. It's said that swimming is helpful to the whole body exercise and can also strengthen the coordination of the whole body. I looked up some information and combined with my own experience, I really found that swimming has very good exercise value for the human body.

First of all, it has a good effect on the cardiovascular system, and swimming plays a very important role in improving the cardiovascular system. The stimulation of cold water can promote blood circulation through heat regulation and metabolism; In addition, the pressure and resistance of water also play a special role in the heart and blood circulation. When swimming on the water, the water pressure on the body has reached 0.02-0.05 kg per square centimeter. When diving, with the increase of depth and the change of physical conditions, the pressure will increase, and the speed of swimming will also increase the pressure load. The muscle tissue of atrium and ventricle can be strengthened, the volume of heart cavity can be gradually increased, and the beating times of heart can be reduced. This can preserve the activity of the heart, but it can improve the whole blood circulation system. When resting, systolic blood pressure increases, systolic blood pressure decreases, and blood pressure value becomes more favorable. The elasticity of blood vessels has also improved. According to the statistics of relevant experts, the average person's heart beats about 66-72 times per minute in a quiet state, and the stroke output is about 60-80 ml, while those who take part in swimming exercises for a long time contract about 50 times under the same conditions, but the stroke output reaches 90- 120 ml.

Secondly, it has a good effect on the respiratory system. In swimming practice, the metabolic process and the saving of cardiovascular system work are inseparable from a large amount of oxygen supply. However, because water compresses the chest and abdomen, it is more difficult to inhale. Someone has done special experiments. When swimming, people's chest is under the pressure of 12- 15 kg of water, so in order to get enough oxygen for the body, the respiratory muscles must be constantly overcome. In addition, when swimming, exhalation is generally done underwater, and the density of water is much higher than that of air, so it is necessary to use force to exhale, so that both inhalation and exhalation can increase the contraction force of respiratory muscles, thus enhancing the function of respiratory system and increasing vital capacity. The average healthy person's vital capacity is 3000-4000 ml, while those who often swim can reach 5000-6000 ml. After swimming, I really feel that my lung capacity has increased a lot, from 3500 to 4300.

Can improve human skin: In the process of swimming, the body wants to ensure sufficient temperature due to the stimulation of water temperature. Skin blood vessels play an important regulatory role. Stimulation of cold water can make skin blood vessels contract and prevent heat from spreading outward. At the same time, the body will intensify the generation of heat, dilate the blood vessels of the skin and improve the blood supply of the blood vessels of the skin, so that long-term exercise can strengthen the blood circulation of the skin. In addition, water is a very soft liquid. Because of the action of water waves, it constantly rubs the human epidermis and makes the skin relax and rest better, so people who often take part in swimming exercises have smooth and soft skin.

However, there are many precautions in swimming. If you are not careful, it may cause bad consequences or endanger people's lives. Pay attention to the time every time you swim, because sometimes you don't feel very tired when you are in the water, but you often feel very tired when you go ashore, so you should pay attention to your physical strength and control your time every time you go into the water. You will feel cool when you are immersed in water. But if the soaking time is too long, or the water temperature is too low, people will have blue lips, pale skin, goose bumps and even chills because of hypothermia. Therefore, beginners should not stay in the water for too long at a time. Generally speaking, it is appropriate to stay in the water for 10 to 15 minutes. People who are used to swimming training can stay in the water for a longer time, but after leaving the water, especially on windy days, they must immediately dry their bodies with dry towels to avoid catching cold.

I used to pull my muscles several times while swimming, which was very painful and dangerous. In fact, most leg cramps occur in toes, arches and the back of calves when swimming, which is mainly caused by insufficient warm-up activities before swimming. If you suddenly jump into the water without doing enough warm-up exercise, the cold water temperature will stimulate and make the blood vessels of the skin and muscles contract a lot, and the blood flow will decrease and slow down, thus causing cramps. Sometimes staying in the water for too long: the energy in the body is constantly consumed, and lactic acid accumulates in the muscles, leading to muscle fatigue and cramps. It's dangerous to get cramps when swimming, so do warm-up exercises before going into the water, and then drench your body with cold water before going into the water to adapt your body to the water temperature. If you cramp in the water, don't panic. You can take a breath first, then stand at the bottom of the water and massage the cramped part with your hands, and try to tilt your feet upwards, and gradually you can return to normal. If it doesn't get better, you can try to float on the water and swim slowly back to the shore with your arms. If you are not sure to swim back to the shore, you should call for help as soon as possible.

Swimming does play a great role in maintaining human health and has a long history. Modern swimming originated in England. From 65438 to the 1960s, swimming activities in many parts of Britain were quite active. 1828, Britain built the first indoor swimming pool at Liverpool George Pier. By the 1930s, this kind of swimming pool appeared in major cities in Britain. 1869 65438+ 10, the Federation of Metropolitan Swimming Clubs (now the predecessor of the British Amateur Swimming Association) was established in London, and swimming was officially fixed as a special sport. Then it was introduced to the British colonies and spread to all parts of the world.

With the development of swimming, swimming can be divided into practical swimming and competitive swimming. Practical swimming is divided into side swimming, diving, breaststroke, treading water, lifesaving and military swimming; Competitive swimming is divided into breaststroke, freestyle, backstroke and butterfly.

Since the first Olympic Games (1896), competitive swimming has been included in the official Olympic events. Today, all kinds of tournaments and international large-scale competitions constantly promote the development of competitive swimming, make its technical movements more perfect, and create outstanding achievements one after another. However, in the past, many events were won by European and American athletes. With the development of swimming in China, we have made many good achievements in the field of swimming and created many hibiscus in water.

I hope I can stick to it, feel the freedom and comfort in the water and make swimming a part of my life.