Why do people want to sleep when it is very hot in summer?

There is a proverb called "Spring sleepy autumn sleepy summer sleepy". The high temperature in summer really makes people feel depressed all the time, especially at noon. Being able to take a nap at this time can make people refreshed and continue to work energetically in the afternoon. So some people vividly say that taking a nap is equivalent to drinking half a catty of milk. But we should also pay attention to it, otherwise it will be counterproductive. Don't go to bed immediately after a meal: generally, it is better to arrange a nap half an hour after lunch, and don't go to bed immediately after a meal. Because I just had lunch, my stomach was full of food and my digestive function was moving. Taking a nap at this time will affect the digestion of my stomach. Don't take a long nap: 15~30 minutes is the most suitable time for a healthy nap, and the longest time should not exceed 1 hour. If it takes too long, you will wake up with a slight headache and general weakness, and it is not easy to wake up at this time. It is best to extend it to 1~ 1.5 hours, a complete sleep cycle. And the nap time is too long, and it is easy to affect sleep at night. You can't sleep on your stomach in the afternoon Some office workers have no time to go home at noon, so they just sit at their desks or take a nap. I don't know that these "sleeping positions" are not only not conducive to eliminating fatigue, but also harmful to health. Because when the human body is sleeping, the muscles of the whole body relax, the blood circulation slows down, and the blood supply to the head decreases. Sitting for a nap because of posture, the brain has less blood supply, which makes people feel dizzy, dizzy and tired after waking up. As for resting at the desk, this method is not desirable. Because sleeping at the desk will oppress the eyeball and lead to high intraocular pressure. If you do it every day, it will make the eyeball swell and the axis of the eye grow, which will lead to high myopia and damage your vision. The ideal nap posture should be lying down comfortably, supine or lying on your side, preferably lying on the right side with your head high and your feet low. This can reduce the pressure on the heart, prevent snoring and help the food in the stomach move to the duodenum. Don't force a nap. It is generally believed that everyone should take a nap in summer, especially the elderly who are in poor health. I think a nap helps to recover from physical fatigue. But experts believe that a nap is not suitable for everyone. There are three kinds of people who are at great risk of taking a nap: one is people over 65 years old or above 20% of standard weight; The other is people with very low blood pressure; The third kind of people have serious obstacles in their blood circulation system, especially those who are often dizzy due to narrowing of cerebral vessels. Because after lunch, the blood in the brain will flow to the stomach, the blood pressure will drop, and the oxygen supply to the brain will decrease. If these people take a nap at this time, it is easy to have a stroke due to insufficient blood supply to the brain. "Summer nap" is also called "summer burnout" in medicine. It is because the summer is hot and the temperature is too high that the human body sweats a lot, and with the sweat, a lot of potassium is discharged, and because potassium can not be replenished in time, people are very tired and depressed in summer. Potassium is an indispensable element for human body. The content of potassium in general adult is about 65438 0.50 g, and its main function is to maintain the normal function of nerves and muscles. Therefore, once the human body lacks potassium, normal exercise will be affected. Potassium deficiency in summer not only reduces energy and physical strength, but also reduces heat resistance, making people feel tired and weak. Severe potassium deficiency will lead to acid-base imbalance, metabolic disorder, arrhythmia, muscle weakness and laziness. At this time, some people drink too much salt and boiled water in order to make themselves sweat less. As everyone knows, it is easy to increase the burden on the heart and make the balance of potassium and sodium in the body unbalanced. Appropriate potassium supplementation is beneficial to improve the balance of potassium and sodium in the body, which can not only prevent the blood pressure from rising, but also prevent the blood pressure from being too low. Here are some foods with high potassium content. First, buckwheat, corn, sweet potatoes, soybeans and other foods have high potassium content. 2. Among fruits, bananas contain the most potassium. 3. Among vegetables, spinach, amaranth, coriander, rape, cabbage, celery, green onion, green garlic, lettuce, potato, yam, fresh peas, edamame, etc. It contains high potassium. Fourth, seaweed is rich in potassium. For example, laver contains potassium1.640mg per100g, which is 75 times that of sodium. The potassium content of kelp is 22 times that of sodium; The potassium content of Sargassum fusiforme is 3. 1 times that of sodium. So, laver soup, steamed fish with laver, laver balls, cold kelp silk, kelp stew and so on. They are all top potassium supplements in summer.