My longest session I think I've ever played was about a 9 a.m. to 3 a.m. run on a weekend with Burning Crusade (I was getting my Arcatraz Key, if that means anything to anyone, and we started Botanica around midnight). I stopped to eat, use the bathroom, and come to think of it, I believe I went to church at the 5 p.m. between them. That said, I would get up, walk around for a bit, stretch, and do those sorts of things.
This is quite tragic, but the fact that he never moved, that is really just an awful accident.