The normal temperature of the human body is as high as 36 or 37. Why only 33? Obviously lower than outside, why do you feel unbearable heat?

The human body constantly produces heat because the body is metabolizing. Simply put, the human body needs to generate life-sustaining energy, but just like oil refining, we can't use all the substances in useful places. When we generate energy, we will generate some heat and constantly radiate it to the outside world. When the temperature outside is high, it will slowly emit, and at the same time, sweat will not be discharged, which will make you feel bored, even fidgety and dizzy, and you will feel very hot.

The normal body temperature of the human body is around 37℃. But this does not mean that people are most comfortable when they keep the temperature of 37℃ in clothes or houses. Because the heat generated by human metabolism must be radiated at a certain speed. If the ambient temperature is too high, the heat can't be dissipated and accumulated in the body, people will feel very uncomfortable. At this time, the human body will excrete a lot of sweat and reduce the body temperature by evaporation and heat dissipation. Only when the temperature is lower than the body temperature can the body's heat be freely emitted. However, when the temperature is too low, the heat is dissipated too quickly, which exceeds the normal heat dissipation speed of the human body, and the human body will feel cold again. At this time, it is necessary to wear appropriate warm clothes to prevent the heat of the human body from radiating outward.

According to experiments at home and abroad, the upper and lower limits of comfortable temperature are 19-24℃ in summer and 17-22℃ in winter. The human body always keeps its body temperature constant. When the ambient temperature exceeds the upper limit of comfortable temperature, people will feel hot, and when it exceeds 37℃, people will feel extremely hot. The upper limit of temperature that people can tolerate is 52℃. On the contrary, when the ambient temperature is lower than the lower limit of comfortable temperature, people will feel cold and cold; If it is below 0℃, it will feel cold. For people who are generally engaged in outdoor activities and wear appropriate clothes, the lower limit of tolerable temperature is about MINUS 34℃.

Perceived temperature is also related to wind speed and humidity. The above only talks about cold and heat from the temperature level, which is not comprehensive. In fact, the so-called cold and hot are human feelings, which are not exactly the same as the actual temperature. Perceived temperature is not only related to air temperature, but also related to wind speed and humidity. For example, it rains in the south in winter, which makes people feel cold. When the wind blows in the north, I feel biting cold. Before the arrival of typhoon or rainstorm in summer, because the temperature is higher than the body temperature, the temperature plays a heating role on the human body, and people can only maintain the body temperature balance by sweating and consuming calories. If the air humidity is high at this time and the sweat does not volatilize, the human body will feel sultry and abnormal. If the cool breeze in Xulaili accelerates the release of human heat at this moment, the human body will feel cool immediately. All these show that when we talk about cold and heat, we can't ignore the role of wind and humidity.