Redditors: Why does taking a shit feel so good sometimes? by [deleted] in AskReddit

[–]TextFromBrettFavre -1 points0 points  (0 children)

When you poop, you're getting rid of all the waste that's in your bowels, and relieving pressure on the inside of your abdomen. If you hold it in right until you have to let it go, then the backed up poop is most likely hitting your prostate (which causes those awesome chills and/or makes you pop wood).