What are probably pysically the strongest HW´s ever and for what reasons? Some examples IMO: George Foreman, made bodybuilding exercises with very high weights... Primo Carnera, lifted also very much... Jose Manuel Urtain, was a powerlifter before he started boxing...
Jack Johnson and Joe Louis were very strong men,Jack manhandled Jeffries in their fight and louis moved Carnera around with ease ,Ali was also a strong heavyweight,Joe Hess ,the Karate champion commented on his power.
Tony Halme:yep [url]http://www.boxrec.com/list_bouts.php?human_id=7863&cat=boxer[/url] [url]http://www.youtube.com/watch?v=Oh3PrxCaL7U[/url]
An often overlooked heavyweight of great strength was Jess Willard. Willard did plenty of manual labor in his youth and was a very strong guy.