Running instead of constipation may be caused by the lack of water in the body after exercise, or it may be caused by running right after eating, intestinal polyps and other reasons. 1. Lack of water in the body: the body will consume a lot of water in the process of running, if you do not replenish water in time, it may cause constipation. 2. Running immediately after eating: running just after eating will increase the blood in the muscles and lead to lower blood in the digestive system. This will make the peristalsis of the stomach and intestines weaker, which in turn will affect the digestion of food, thus resulting in constipation instead of running. 3. Intestinal polyps: patients with intestinal polyp disease will lead to narrowing of the intestinal lumen space, defecation is impeded and lead to fecal retention in the intestinal tract, which has little to do with running. This is mainly because the patient himself has a gastrointestinal tract underlying disease. It is recommended that patients who are constipated instead of running should go to the hospital in time to have the cause clarified under the guidance of the doctor.