posted on Mar, 3 2007 @ 11:40 PM
If there is urine in your bladder, it is involuntary that your body be tense to keep it in. When you use the restroom, your muscles are relaxing, thus
letting the urine come out.
When your body is put in warm water, it will automatically relax causing those muscles to release and for the urine to flow freely.
That's why when you walk into a hot shower or bath, you'll feel the urge to pee.