Why do you want to sleep when the weather is hot?

When the weather is hot, I feel sleepy. Spring has arrived, and the temperature is high and I am particularly sleepy these days. Spring sleepiness is a temporary physiological phenomenon caused by natural climate and rising temperature. In cold winter and early spring, people are affected by low temperature, and the sweat glands of the skin contract to reduce the heat emission in the body and keep the body temperature constant. In spring, the temperature rises, the skin pores stretch, the blood supply increases, and the oxygen supplied to the brain decreases accordingly, which affects the work of the brain and makes the biological clock less accurate. In winter, due to the lack of ultraviolet rays and sunlight, the body lacks enough vitamin D, which reduces the body's immunity and working ability. In addition, the intake of vitamins is also less, so spring is coming, and most of the body functions are in a semi-lethargic state. Therefore, some people call this "spring sleep".