Although I have NO IDEA why Mariusz Pudzianowski would take up MMA fighting after Strongman, he is without question - tough as nails.
He did last 7 minutes with Tim Sylvia. And not for nothing - Tim was the former UFC heavyweight champion in 2003, and was the interim heavyweight champ in the UFC in 2005, only five years before fighting Mariusz.
If I had to guess, Mariusz could probably completely destroy most people, and even plenty of pro fighters who weigh much less than he does.