In medicine, the contraction of peristalsis of the stomach wall is divided into tense contraction, permissive diastole and peristalsis. 1. Tensive contraction: Tensive contraction is a slow and continuous contraction maintained by the smooth muscle of the stomach wall, which ensures that the stomach is in a certain degree of shape and position, prevents gastric ptosis, and facilitates the advancement of food in the direction of the pylorus. 2. Tolerance diastole: Tolerance diastole refers to the reflex diastolic movement of the fundus and the body of the stomach when eating, due to the stimulation of the receptors of the mouth, pharynx and esophagus by the food, which can make the stomach hold a large amount of food and avoid the abnormal increase of the pressure inside the stomach. 3. Peristalsis: Gastrointestinal peristalsis is the rhythmic peristalsis of the stomach and intestines due to the innervation of muscles, peristalsis can play a role in stomach grinding of food to promote food absorption and digestion, but also to promote the advancement of food, so that the food is gradually pushed into the duodenum.