system
Given the following post, respond as if you're commenting on Reddit:
human
What is actually happening when we are able to temporarily "walk off" the need to defecate?

Is it physical or psychological?
gpt
Your can clench your external anal sphincter and hold off defecation. This breaks the defecation cycle and the feces is forced back into the colon from the rectum, where more water is absorbed, potentially leading to hardened stools and constipation. You have no conscious control of your internal anal sphincter.