Wilder. Not many people get to 6'7 (2mts), have a 7ft long reach and can knock heavyweights out from the other side of the ring
I remember seeing Sonny Liston’s hands and at first glance I thought he had black boxing gloves on, turns out it was just his hands
Jimmy Bivins and Crisanto Espana had abnormally long arm lengths for their particular size and weight. And I won't even get into what Andrew (Six-Heads) Lewis brought as an abundance to the table.
My dad's heart rate was in the 30-40 range when he played football and basketball. The army classified him as 1-A. He had a distinct advantage over other athletes in stamina, especially late in the game when most people are tiring out. I am the same height as Liston with an 80' reach. It's really not hard to believe. His hands were even bigger than mine and he had a wider chest. George Chuvalo said his short neck probably helped him in absorbing punches. His head wouldn't bounce his brain around as much as long necked individuals Hagler and Holyfield also had very strong neck muscles and shoulders which probably helped minimize the damage from impacts.
Joe Grim, according to a doctor at the time, had an abnormally small brain and sluggish nerves and was, essentially, too stupid to be knocked out.
I remember reading something about Sanchez having such a low resting heart rate, and such good aerobic capacity that his heart rate would be back down to its usual rate in about 45 seconds. Meaning, by the time he went back out after a round had ended, he'd be as fresh as the round before. Obviously that doesn't account for accumulated damage in the match, but it does show how he came on so strong in the late rounds compared to his opponents.
His reach is not 7', & while his arms are long, for his height not extremely long at all. He is the height of the average NBA player, & their reaches are 7'. He has gifts, but no abnormality or difference in kind, but more of size & power than one would expect.
