Swimming time should not be too long, preferably no more than two hours

Swimming is a popular leisure sport, especially in summer. Many people like to soak in the swimming pool for half a day, believing that the longer they swim, the better they can exercise their body and cool down. Experts remind that swimming time should not be too long, otherwise it will harm your health.

The swimming time should be kept between one and a half hours and two hours, and the training of athletes is generally no more than about two hours.

Experts remind citizens that the best swimming time is 20 to 45 minutes. Do not extend the time to cool down, otherwise it will affect your health.

It is easy for people to dissipate heat in water. In order to avoid excessive heat dissipation, the human body will produce a protective reflex, causing the blood vessels in the skin to compress. So when you first go into the water, your skin is white. After swimming in the water for a while, your blood circulation speeds up, the heat increases, and your skin turns from white to red.

If you spend too long in water, the heat generated by your body will be lower than the amount of heat dissipated in the water, and your body's temperature regulation function will be destroyed. The arteries in your skin will contract, the venules will dilate, and the blood will stagnate in the subcutaneous veins, causing cyanosis of the skin, black lips, goose bumps on your body, and even convulsions.

If you have been in the water for a long time, once this situation occurs, swimmers must get ashore immediately, wipe off the water on their bodies, bask in the sun, and put on clothes as soon as possible after they warm up to prevent colds, muscle strains and other illnesses.

In addition, most of the tap water supply systems used in cities are disinfected with chlorine. When people swim, they come into direct contact with chlorine, which evaporates from the water and is directly absorbed by the skin. Generally, chlorine inhalation within 20 minutes has no significant effect on the human body, but soaking in water for a long time can cause illness due to the invasion of chlorine.

In the hot summer, people like to soak in swimming pools to cool off, and swimming pools have become places where crowds gather. So when people swim, they will inevitably bring skin excretions, shed hair, mucus, and even urine and swimsuit dyes into the water. Contaminated water can cause diseases of the eyes, nose, ears, throat, skin, gastrointestinal tract, reproductive system, etc. Children, in particular, have weaker resistance. If they stay in the water for too long, they are more likely to be attacked by germs. Therefore, children’s swimming time should be moderate, and they must rinse their entire body before and after swimming.