Normally, human growth hormone is secreted in pulses, once every 3-4 hours, with about 6-8 pulses throughout the day, but the peak of secretion is between 9:00 pm and 1:00 am at night. It has been found that the secretion of human growth hormone can exhibit a strong circadian rhythm with large diurnal fluctuations. Growth hormone is secreted 2-3 times more at night than during the day, and after one hour of deep sleep, the secretion of growth hormone is greater than half of the total amount of the day. Generally, after 9:00 pm, the secretion of growth hormone gradually increases and continues until about 1:00 am, which is the peak of growth hormone secretion in a day, while 6-7:00 am is another secretion peak, and the secretion of growth hormone can gradually decrease after the degree. Therefore, during the growth period of children, it is recommended to let them go to sleep before 9:00 at night. Children’s height can be negatively affected if they stay up late for a long time.