The weather is hot in summer. Many people like to swim in summer. It's good for your health to swim properly. What are the benefits of swimming in summer? What should we pay attention to in summer? Let's have a look.
What are the benefits of swimming in summer?
1. Improve the function of respiratory system
One of the main characteristics of water is its incompressibility. Because the density of water is more than 800 times higher than that of air, the pressure on people in water is much greater than that in air. That's why beginners find it hard to breathe in the water. As the pressure on the chest and abdomen increases in the water, it forces the breathing muscles to breathe with greater force. Therefore, regular swimming can increase the strength of respiratory muscles and improve the function of respiratory system. The most obvious example is the value of vital capacity. The vital capacity of swimmers can reach 4000 to 6000 ml, or even 7000 ml, while the average person only has 3000 to 4000 ml.
2. Improve the function of cardiovascular system
The cardiovascular system includes the heart, the lungs, and the blood vessels responsible for delivering inhaled oxygen to muscle cells. In order to overcome the resistance of water, more energy should be used to speed up the heart rate and increase the cardiac output. Insist on long-term swimming exercise, the heart volume increases with exercise, the heart muscle contracts powerfully, the quiet heart rate slows down, the output of each stroke increases, the blood vessel wall thickens, the elasticity increases, and the efficiency of the cardiovascular system is improved.
In addition, when swimming, the human body is in a supine position, and the pressure of water on the skin forms a kind of massage effect. Therefore, it is easier for the blood of the limbs, especially the legs, to flow back to the heart than when standing on the land. Moreover, the resistance of water makes it difficult for muscles to exert explosive force like on land. These characteristics are very suitable for middle-aged and old people to exercise, which can not only strengthen their physique, but also can not easily cause accidents due to too intense exercise.
3. Improve the ability of muscle system
Swimming is a whole body sport, more muscle groups can participate in metabolism and energy supply than other athletes.
Although swimming can't build strong and bulging muscles, it can improve the strength and coordination of many muscles, especially the muscles of trunk, shoulder belt and upper limbs. Because swimming in water needs to overcome great resistance, and swimming is a periodic exercise, long-term exercise can improve muscle strength, speed, endurance and joint flexibility.
There is also a great advantage of swimming, that is, the improvement of flexibility. This enables people to continue swimming when they are unable to engage in other sports due to their age limit. Due to the wide range of physical activities during swimming, people who regularly swim will become more flexible and soft. Moreover, the correct swimming technique requires the muscle to stretch before contracting and exerting force, which is conducive to continuously improving flexibility and strength.
4. Mechanism of improving thermoregulation
Because the temperature of water is generally lower than the air temperature, and the thermal conductivity of water is dozens of times stronger than that of air, the heat lost by people in water is far faster than that in air. Regular swimming can improve the ability of body temperature regulation, so as to be more able to withstand the changes of external temperature. Especially in winter swimming, it can improve this aspect.
5. Make the proportion of body composition more reasonable, so as to build a healthy body
If you often watch swimming competitions, you will be envious of swimmers' round, slender, well proportioned muscles and strong bodies. Because of the influence of muscle working style, swimmers generally have long stature, broad shoulders, flexible waist and legs, and a symmetrical body shape. Maybe someone will say, I want to lose weight through swimming, why is it not effective? In fact, to lose weight through sports, we must achieve certain intensity, adhere to enough time, and persevere. If only three days to fish, two days to the net to swim a little leisurely swimming pool, of course, will not have any effect. If you run, bike or do any other exercise in this way, the result is the same.
6. Disease prevention, treatment and rehabilitation
Because of the stimulation of cold water, long-term swimming exercise can enhance the body's ability to resist the cold and adapt to the environment, prevent cold and other diseases, and make the body stronger day by day. Because the body lies flat when swimming, plus the buoyancy, can make the spine fully extended. Swimming can also be used as a exercise prescription to treat some chronic diseases, such as chronic gastrointestinal disease or chronic bronchial asthma and so on. For some people who are not suitable for upright exercise, such as the patients with excessive obesity, if they take running and other ways, due to the effect of gravity, their legs and feet are overloaded, which is easy to cause injury. At this time, swimming is a good alternative to exercise.
What should we pay attention to when swimming in summer?
1. Swimming immediately after strenuous exercise will aggravate the burden on the heart; the sharp drop of body temperature will weaken the resistance and cause cold, pharyngitis, etc.
2. Long time exposure can produce sunburn, or cause acute dermatitis, also known as sunburn. In order to prevent sunburn, it is better to use an umbrella to shade the sun after landing, or to rest in a shady place, or to protect the skin with a bath towel, or to apply sunscreen to the naked part of the body.
3. During menstruation, when swimming, germs are easy to enter the uterus, fallopian tubes and other places, causing infection, resulting in irregular menstruation, excessive menstruation and prolonged menstruation.
4. In swimming, if the leg or foot cramps, do not panic, can be forced to kick or do jumping action, or forced massage, pulling the cramped part, and call for help.
5. When swimming in natural waters, do not jump into the water. It is not suitable to swim in the water where the surrounding and underwater conditions are complex, so as to avoid accidents.
6. To be clear about their own physical health, usually limb cramps are not suitable for swimming or swimming in deep water. To prepare for the water, first exercise the body. If the water temperature is too low, first wash the body with water in shallow water, and then swim in the water when the water temperature is suitable. Students with dentures should take off the dentures to prevent them from falling into the esophagus or trachea when choking water.
7. Be aware of your wateriness. Don't try to be brave when you are in the water. Don't dive and swim rashly. Don't fight with each other to avoid drinking and drowning. Don't swim in the rapids and whirlpools, let alone after drinking.
8. If you suddenly feel uncomfortable in swimming, such as dizziness, nausea, panic, shortness of breath, etc., you should immediately go ashore to rest or call for help.
9. Swimming on an empty stomach will affect appetite and digestive function, as well as the occurrence of dizziness and fatigue in swimming; swimming on a full stomach will also affect digestive function, as well as stomach spasm, even vomiting and abdominal pain.
10. Don't go out swimming alone, and don't go to places where you don't know the bottom and water conditions or are relatively dangerous and where drowning accidents are appropriate. Choose a good swimming place, and understand the environment of the place, such as whether the reservoir and bathing place are sanitary, whether the underwater is flat, whether there are reefs, undercurrent, weeds, and the depth of the water area.