In ancient times, early morning was called dawn, dawn, cock crow, and sometimes it was called late at night.

Dawn: Dawn refers to the time when the day is about to dawn or just dawn, which is recorded in "Shi Gao Ancestors": "Dawn goes around Wancheng for three coins." Sima Zhen Suoyin: "Li, you are better than me, better than Dawn."

Dawn: Dawn means that the morning has just begun to shine, and the morning sun shines or seems to shine. From Song Yang Wanli's poem "Under the Port of Faming Stage": "It's not like it's cold today when the hedge teacher releases the boat at dawn."

Crow: On the 20th birthday, it is from 1: 00 to 3: 00 in the morning, also called crow.

Late at night: Late at night refers to the period from midnight to dawn. It is a sentence in Liu Ji's poem "Mid-Levels Temple" in the Ming Dynasty: "In the middle of the night, the fox breaks the tomb, and the Buddha lamp is like a ghost lamp."

Early morning refers to a period of time from midnight to dawn, starting at twelve o'clock in the evening and ending at six o'clock in the morning.

When the morning comes, that is, after entering the zero point, most normal physiological activities of the human body may be weakened, and some physiological characteristics that are not available during the day will also be displayed. If you can't do some better rest and adjustment in the early morning, it is likely to affect your work and study the next day. Therefore, it is very important to keep a good habit of work and rest.

Yin is on duty, then "lung" is on duty. At this time, the yin and yang of the earth began to change, from yin to yang, and deep sleep can replenish lung qi. The best way to moisten the lungs is to sleep deeply.

Yin Shi is the time when human blood began to redistribute. How much blood the heart needs and how much blood the kidneys need are distributed by the lung meridians. In order to keep the lung meridian vigorous, deep sleep is needed.

Secondly, strengthening the spleen can replenish the lungs. According to the theory of five elements in traditional Chinese medicine, kidney belongs to water, lung belongs to gold and spleen belongs to soil. Soil can produce gold, therefore, lung qi is insufficient, so we should use the method of cultivating soil to produce gold to strengthen the spleen and benefit the lungs. Gold can produce water, and tonifying the lungs can also tonify the kidneys, and gold and water are born together.

1, Yin Shi time: 3 am -5 am.

2, timely meridian: lung meridian, at this time the lung meridian is the most prosperous.

3, the principle of yin qi health: sleeping in yin qi is the best protection for the lung.

4, the principle of yin in health: the human body must sleep in the yin.

5, the characteristics of the lung meridian: the lung governs the whole body's qi, and has the function of regulating the whole body's viscera and meridians. The lung assists the heart to control the whole body, regulates qi and blood, nourishes health, and communicates and nourishes viscera everywhere.

6. Clinical manifestations of lung meridian problems: excessive lung qi, haggard face, pain in chest, back and limbs, causing upper respiratory tract infection, and severe chronic asthma and emphysema. If lung yin is heavy and yang is weak, people's body will become dark, weak, afraid of cold, easily tired and sad.