The left side of the rib cage has been jumping below may be and heart beating, nerve beating, muscle spasm, transverse colon peristalsis and so on have a relationship. 1. Heart beating: the heart is located under the left rib cage, the left midclavicular line and the fourth rib intersection inward 0.5-1.0cm for the apical beat position, so the heart will be touched under the left rib cage beating. 2. Nerve throbbing: keeping a posture for a long time will make the local blood circulation poor, such as under the left rib cage is in a state of compression, and may produce nerve throbbing symptoms over time. 3. Muscle spasms: Cold and injury to the muscles below the left rib cage may also cause muscle spasms and a throbbing sensation. 4. Transverse colon peristalsis: The organ below the left rib cage has a transverse colon, and the throbbing may be related to the peristalsis of the transverse colon, and there will be a throbbing sensation outside of the body when the transverse colon peristalsis occurs. It is recommended to go to the hospital for examination after the symptom of jumping all the time under the left side of the ribcage, and find out the reason and then treat it under the guidance of the doctor.