What, still nobody to try this? Cowards and scoundrels all of you!
Seeing as getdare is full of scaredy cats (or people that don't have tape measures) I have no choice but to give this a go:
Results
Before: 78cm = ~31 inches
After: 85cm = ~33.5 inches
In related news, have you ever tried operating a tape measure while desperately struggling not to release an enema? Definitely not my proudest moment.
It took two tries, because the first time I accidentally used the inches and got the result that taking an enema had actually shrunk my stomach by 50cm.
