system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why do we dance/move frantically when we're trying to hold our bladder?

We've all had to hold it in because someones in the toilet but what actually happens to you internally that prevents you from wetting yourself.
gpt
The simplest answer is that the frantic movement tells your subconscious/autonomic brain that this is not an appropriate time to urinate.  Then your autonomic nervous system stops the contractions of the bladder muscles and clamps the internal sphincter shut to prevent urination.  This only works so long before the Micturition relfex exerts itself again and eventually wins causing you to urinate no matter how much you jump or wiggle around.