Experts said： The higher the body temperature in the normal range, the stronger the immunity.

　　"My temperature is only 35.6℃, is it normal?" "My child’s temperature is 37.2℃. Is it a fever?" "How does my temperature rise and fall in a day?" "I saw on the Internet that higher body temperature means stronger immunity. Is that right?" … … Since the nationwide monitoring of body temperature and the comprehensive investigation of COVID-19 in Wuhan on February 6th, people have paid unprecedented attention to body temperature.

　　Body temperature is one of the important indicators to measure human health. As we know, whether it is a serious illness or a minor illness, a chronic disease or an acute disease, the first thing a doctor does when entering a hospital is usually to measure the patient’s temperature. If we are not feeling well, we will also take our temperature. On February 9th, in response to the public’s many doubts about body temperature, this newspaper invited relevant medical experts to elaborate on body temperature.

　　How much is the body temperature normal?

　　Shu Yingchun, deputy chief physician of Wuhan Children’s Hospital: Normal body temperature is not a specific temperature point, but a temperature range. The body temperature in the deep part of the body is relatively constant, which is called deep body temperature; However, the surface temperature is affected by many factors, with great changes and differences, which is called surface temperature. The clinical body temperature refers to the average deep temperature. Generally, the body temperature of the mouth, rectum and armpit is represented, and the rectal body temperature is closest to the deep body temperature. The normal range is: oral sublingual temperature is 36.3℃-37.2℃, rectal temperature is 36.5℃-37.7℃, which is higher than oral temperature (0.2℃-0.5℃) and axillary temperature is 36.0℃-37.0℃.

　　The standard of normal body temperature is based on the value of most people, not the absolute value of individuals. Each individual’s basal body temperature is different, so the same temperature, for one person, may be normal body temperature and will not cause discomfort, while for another person, it may be fever. The basal body temperature is generally the oral temperature measured immediately after sleeping for 6-8 hours without any interference, such as standing up, moving, eating, etc. Night shift workers can measure it after sleeping for 6-8 hours.

　　How to measure body temperature?

　　Shu Yingchun, Deputy Chief Physician of Wuhan Children’s Hospital: The temperature is measured by mercury thermometer. When measuring the body temperature, the mercury column of the thermometer should be thrown below 35℃, then wiped and disinfected with a cotton swab dipped in alcohol, and then held under the armpit for 5 minutes. When reading the thermometer value, the eyes should be on the same plane as the highest mercury. Although the electronic thermometer is convenient and safe, it is prone to errors. It can be added or subtracted from the temperature measured by the mercury thermometer, thus reducing the errors.

　　Why does the body temperature fluctuate?

　　Shu Yingchun, deputy chief physician of Wuhan Children’s Hospital: The body temperature is not fixed, but it fluctuates with factors such as gender, age, day and night, exercise and mood changes, but this change is often within the normal range.

　　Gender factors: Generally speaking, women are slightly higher than men, and women are slightly higher in premenstrual and early pregnancy, and ovulation period is lower.

　　Age factor: Neonatal body temperature is easily influenced by external temperature, which can be slightly higher than that of adults. The elderly have low body temperature because of their low metabolic rate.

　　Time factor: Generally, the body temperature is the lowest at 2-5 in the morning, and the highest at 5-7 in the afternoon, with a range of about 0.5℃-1℃. If you work at night for a long time, your body temperature will increase at night and decrease during the day.

　　Emotion and exercise: Sympathetic nerve is excited when emotion is excited, and skeletal muscle contracts during exercise, which can raise body temperature slightly.

　　In addition, the change of outside temperature and eating can make the body temperature fluctuate.

　　Is low body temperature bad for immunity?

　　Recently, it is widely rumored on the Internet that the normal human body temperature of 37℃ has become a history, which has dropped by 0.4℃ in less than 200 years since the 19th century. For every 1℃ drop in body temperature, the immunity will drop by about 30%. When the body temperature rises by 1℃, the immunity will be improved by 5-6 times.

　　Shu Yingchun, deputy chief physician of Wuhan Children’s Hospital: We take 37.3℃ as the temperature of children’s fever in clinic. When we measure the temperature of children with non-fever diseases, it is almost lower than 37℃. However, there is no statistical data to support whether it has dropped by 0.4℃ in 200 years.

　　Professor Wang Xiaochuan, deputy director of the Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, and doctoral supervisor: Although there is no specific research on how much immunity will decrease or increase after the body temperature drops and rises, the higher the body temperature, the stronger the immunity will indeed appear. This is because the higher the body temperature, the more immune cells will be activated in the human body, so that the invading pathogenic microorganisms can be better annihilated and the health of the body can be maintained.

　　How to raise body temperature?

　　[Soak your feet every day]

　　Liao Haolei, Professor of Clinical Epidemiology, School of Health, Wuhan University: Strengthening exercise and nutrition can really improve the basal metabolic rate and basal body temperature. However, "Rome wasn’t built in a day", and exercise and nutrition need long-term persistence. Facing COVID-19, we need to raise our body temperature and enhance our immunity through physical therapy and behavioral therapy: it’s best to wear a hat in winter, soak our feet and take a hot bath every day, and drink more hot water. Now everyone stays at home and can soak their feet three times a day.

　　[gentle exercise]

　　Zhang Qingsong, an expert in sports medicine in the Fourth Hospital of Wuhan, said: If the measurement error is ruled out, there are indeed some people whose body temperature is low for a long time, which is physiological, not pathological. It has no effect on the health of the body. Exercise can temporarily raise body temperature, and the degree of body temperature increase is related to the intensity of exercise.

　　This kind of hypothermia person, after he recovers from exercise, his body temperature will still fall back to his usual level, which is normal and does not need special attention.　

　　According to scientific research, long-term exercise has a positive effect on improving immunity. Exercise can obviously improve cardiopulmonary function and chronic diseases. Long-term moderate exercise can improve the body’s immunity and reduce the risk of infectious diseases. However, during 3~72 hours of intensive exercise, people will be in the "empty window period" of immunity, and they are more vulnerable to pathogen infection than usual.

　　Therefore, at present, under the epidemic situation, it is not recommended to cram for high heart rate and high intensity exercise temporarily, which will reduce the resistance.

　　Therefore, if you don’t have fitness habits, don’t rush to iron or sweat on the treadmill. Young people do flat support and push-ups at home, and walk fast on the treadmill. Middle-aged and elderly people can play Tai Chi and do health exercises. It is a good choice for women to do aerobics and yoga for about 30 minutes. When exercising, the heart rate is between 120 and 150, which not only achieves the exercise effect, but also does not exceed the physical endurance of ordinary citizens.

　　(Reporter Tang Zhifeng Yan Yan Wang Chunyu Li Qing)