In summer, the weather is hot, and many people can't sleep well at night. Therefore, taking a nap is good for their health and can keep enough energy. It is suggested that people take a nap for about an hour every day. Of course, when taking a nap, we should avoid strong external stimuli, because after falling asleep, muscles relax, capillaries dilate, sweat pores are wide, and it is easy to catch a cold or other diseases. You should also pay attention to avoid catching a cold.