We had to film a certain percentage of the 33 hours as proof and that did involve filming them take a leak. That was pretty awkward. Not sure if either of them took a dump though...
Edit: and when I say "film them take a leak" I mean filming them continuing to shake hands WHILST taking a leak...
Two friends at Uni did the longest hand shake (33 hours) which was then broken by "professional record breakers" soon after. To think "professional record breakers" exist is surreal.