The Urge to Shit is an indication of one's closeness to actually shitting. Usually the urge to shit is often answered by a quick trip to the toilet. However, on some occasions the urge to shit has
lurked as a
silent killer, waiting for
the perfect moment to strike. It is often felt in the lower intestinal region and can be quite alarming as it causes tenseness of the muscles in that region.
If the urge to shit is not immediately purged, then it will eventually subside - however it will return (usually within 10 minutes) and bring back the same tense-ness desperation that can happen.
That is why it is always best to shit before a trip - to prevent the urge to shit from occurring. Furthermore it is always best to relieve it's call. And you will know the feeling of shit relief, when this urge has been fulfilled.