The Arrival of 'Chushu' (End of Heat) is the Perfect Time for Health Preservation
Core Tip: Chushu is the 14th of the 24 solar terms in a year. It begins around August 23rd each year when the sun reaches the celestial longitude of 150 degrees. Ancient records state: "When the Big Dipper points to Wu, it is Chushu. The summer heat is about to retreat,潜伏潜藏, hence the name." The "Seventy-two Seasons of the Monthly Ordinances" explains: "Chu means to stop, and the summer heat stops here." At this time, the "Sanfu" (dog days of summer) are over or nearing their end, which is why it is said "the summer heat stops here." There are also sayings across the country, "Chushu brings the cold," indicating that the summer heat gradually subsides.
However, the weather has not yet truly cooled down for autumn. The heat on a sunny afternoon can be just as intense as in the height of summer. In regions south of the Yangtze River, there is a saying, "Autumn tiger," which reminds people that there will still be hot days in autumn, and can also be seen as a final flourish of summer.
Gu Tieqing, author of "Qing Lu Lu," described Chushu as follows: "The local custom is that after Chushu, the weather is still warm, and it takes about another eighteen days before it begins to cool down; the saying goes: 'Eighteen basins of bathing at Chushu,' meaning one will sweat for eighteen days." This means there will still be about eighteen days of sweaty weather ahead.
Chushu symbolizes the final retreat of the southeast monsoon from the Chinese mainland and the beginning of the northwest monsoon's dominance. After Chushu, the weather truly transitions into autumn.
Ancient China divided Chushu into three phases: "First, eagles begin to offer birds as sacrifice; Second, heaven and earth begin to grow solemn; Third, the grain is ripe." During this solar term, eagles start hunting birds in large numbers; all things in heaven and earth begin to wither; "He Nai Deng" refers to the general term for millet, broomcorn, rice, and other grains, with "Deng" meaning mature.
After Chushu, the weather turns cooler. It is hot at noon and cool in the early morning and evening, creating a large temperature difference between day and night. The climate characteristic of "a秋雨一场凉" (one autumn rain brings a drop in temperature) becomes evident. The climate of hot days and cool nights provides good conditions for the body's Yang Qi to be conserved. During each Chushu, people's health preservation should pay attention to the following aspects:
1. Clothing Advice: Do not rush to add more clothes. The meaning of "捂春冻秋" (covering in spring, freezing in autumn) is to prevent the body temperature from being too high in autumn, which is conducive to conserving Yang Qi. Because as heat is expelled, cold must be exchanged in. However, when going out at night, one should add clothes to protect Yang Qi.
2. Sleep Advice: Close windows and doors, and cover the abdomen with a thin blanket to prevent the autumn wind from causing the spleen and stomach to catch cold.
3. Indoor Advice: During the day, if the room temperature is not high, it is advisable not to use the air conditioner. You can open windows to allow air circulation, letting the autumn's cleansing Qi dispel the damp and turbid air left in the room from the summer heat.
4. Disease Prevention Advice: Before the autumnal equinox on September 23rd, the climate is more variable. The temperature tends to be hot before rain and cool after rain, which can easily trigger wind-cold or wind-heat colds. If a cold occurs, it should be treated promptly with dietary therapy to restore balance.
5. Diet Advice: During the Chushu solar term, it is advisable to eat foods that clear heat and calm the mind. It is recommended to select foods based on individual constitution, such as tremella, lily, lotus seeds, honey, kelp, celery, spinach, glutinous rice, sesame, beans, etc., to nourish the body and mind.
The Chushu solar term is a period of transition from hot to cool. The Yang Qi in nature shifts from dispersing to being conserved, and the balance of Yin and Yang in the human body also changes accordingly. Therefore, people's daily routines should be adjusted accordingly. Going to bed early and rising early is a well-known principle. Good sleep can not only eliminate fatigue, protect the brain, and enhance immunity, but also promote development and benefit beauty.
At the same time, ancient people in their sleep health methods emphasized the importance of "Zi Wu Jiao" (sleeping during the Zi and Wu hours)—that is, being in a deep sleep during Zi hour (11 PM - 1 AM) and resting quietly or napping during Wu hour (11 AM - 1 PM). They believed that at the Zi and Wu hours, Yin and Qi intersect, reaching a peak and then a decline, causing an imbalance of Qi, blood, Yin, and Yang in the body, which requires quiet rest to allow the Qi to recover. Modern research has found that from midnight to 4 AM, the function of all internal organs in the body reaches its lowest point; and from 12 PM to 1 PM, the body's sympathetic nervous system is most fatigued. Statistics also show that the elderly who sleep during the Zi and Wu hours can reduce the incidence of cardiovascular and cerebrovascular diseases. Therefore, Zi Wu Jiao has both disease prevention and health preservation significance and aligns with the principles of health preservation.
After the Chushu solar term, the weather gradually cools, and people also transition from preventing heatstroke and cooling down to preventing cold and keeping warm. Everyone knows the principle that "cold originates from the feet," but few notice that the navel is also very susceptible to cold. The skin over the navel is the thinnest, with no subcutaneous fat tissue, but it has rich nerve endings and plexuses, making it particularly sensitive to external stimuli and easily penetrated. If not properly protected, such as exposing the abdomen while sleeping at night or young women wearing cropped tops, cold can easily invade the body through the navel. If the cold directly affects the gastrointestinal tract, it can cause acute abdominal pain, diarrhea, and vomiting; if it accumulates over a long time in the lower abdomen, it can also lead to diseases of the urinary and reproductive systems.
Therefore, in addition to adding clothes according to the weather and covering the abdomen when sleeping at night, you can also massage the navel. The method is to first rub your palms together until they are warm, then place one on top of the other on the navel and rub clockwise and counter-clockwise 100 times each. If cold has accumulated for a long time and the condition is stubborn, you can also take 0.5 to 1 kg of coarse salt (the kind used for pickling), heat it in a pan, place it in a towel pouch, and apply it as a hot compress on the navel.
The focus of health preservation after the Chushu season is to prevent "autumn dryness." Generally, the most comfortable relative humidity for the human body is 40%-60%. Too high or too low will feel uncomfortable. Because the water vapor content in the air is low in autumn, the relative humidity drops. Especially when the relative humidity is below 30%, people will feel dry and rough skin, dry and painful nasal passages, a dry mouth and throat, and constipation, requiring timely preventive measures to avoid developing into a condition ("autumn dryness syndrome").
Dietary health preservation methods are very effective in preventing "autumn dryness." It is especially recommended to eat more cool, juicy vegetables, fruits, and liquid foods, but this should also be determined according to individual constitution. Foods such as cucumbers, tomatoes, winter melon, lily, white radish, carrots, and pears, apples, grapes, water chestnuts, sugarcane, citrus, bananas, persimmons, pineapple, monk fruit, red dates, and soups and porridges are beneficial for supplementing vitamins and increasing water intake. In terms of diet, it is best to eat less of pungent and heaty foods like Sichuan pepper and chili, and even less grilled food, to avoid worsening the symptoms of autumn dryness.
It is hoped that the above small tips related to the Chushu solar term can be of some benefit to everyone's lives. Let us, with grateful hearts, bid farewell to the beautiful and lush midsummer and welcome the fruitful golden autumn!