The normal physiological functions of both the anterior and posterior yin are closely related to the kidneys. Chinese medicine believes that the two yin are the anterior yin and the posterior yin. The anterior yin includes the urethra and genitals, which play a role in urination and reproduction; the posterior yin is the anus, which plays a role in the excretion of feces. Urine excretion, although mainly in the bladder, but depends on the role of the kidney qi, and human reproductive function by the kidney, as for the excretion of feces is also related to kidney qi. Therefore, if the kidney qi is weak, frequent urination, enuresis or scanty urination, urinary closure may occur in urination; in reproduction, spermatorrhea, impotence, premature ejaculation, infertility may occur; in stools, prolonged ejaculation and slippage or constipation may occur and other diseases. Professional medical knowledge can consult a doctor.