As soon as you sit down, you will have a bowel movement. Consider that it may be related to neurosis, proctitis, intestinal space-occupying lesions and other factors. 1. Neurofunctional syndrome: one’s own nervousness, anxiety, irritability and often stay up late, etc., can lead to autonomic nerve disorders, thus causing neurofunctional syndrome, which will stimulate the mucous membrane of the gastrointestinal tract as well as the surrounding muscles, and will appear as soon as one sits down to have the urge to poop phenomenon. 2. Proctitis: when there is inflammation of the rectum, sitting down may involve the rectum so that inflammatory factors stimulate the intestinal tract, there will be the symptom of wanting to poop when you sit down. 3. Intestinal space-occupying lesions: such as intestinal polyps, intestinal tumors, etc., when you sit down, the space-occupying mass will make the intestinal tract compression so that the abdominal pressure increases, and there will be a sit down and want to have a bowel movement. There may be other reasons why you have bowel movements when you sit down, so it is recommended that you go to the hospital and take appropriate measures after examination.