Although each division has its big punchers, lightheavyweights, middleweights, welterweights and lightweights and flyweights usually have a smaller KO percentage than heavyweights. It seems that heavyweights can't take heavyweight punches as well as flyweights can take flyweight-punches. There are plenty of smaller weight fights that go on for a long time when one guy is taking quite some punishement, whereas a heavyweight fight like that will usually end in a KO. Because of this, the smaller fighters will take more punishment. Another factor is that smaller fighters on average throw more punches and thus land more. Thoughts?
Obviously weight matters, not only in brutality, but also in longevity. You'll see no flyweights competing well after forty. I'm personally of the opinion that the Middleweight division is the most dangerous -- a perfect blend of power, speed and chin there to produce a multitude of accidental deaths and hurt fighters.
nah middlewieght is still big for the one punch knock out so there isnt that type of danger to it i would say welter maybe even lightwieght the blend of speed and repetative hard shots can stop a career VERY fast
Which is why 30+ fighters in the HW division are considered the future whereas 30+ in lightweight and welterweight are considered to be on thier last leg.
Generally speaking, lighter weight fighters rely on quickness and reflexes to survive beyond age 30. Power alone won't cut it. Otherwise Teddy Reid would still be a title threat instead of a punching bag who happens to have dynamite in both hands. There aren't many, if any, George Foremans below heavyweight (well, that's unfair to Big George version 2, who had better defense than Reid). I've seen no clear relationship between size, weight, punching power and ability to absorb punches. Manny Pacquiao was KO'd twice as a flyweight but hasn't appeared to be hurt since against larger, heavier punching featherweights and super feathers. Of course, Manny's grown as he's aged - he wasn't quite 20 when he won the WBC flyweight title. At lightweight Roberto Duran was knocked down by Esteban de Jesus yet continued to fare pretty well against some of the hardest hitters in the welterweight, light middleweight and middleweight divisions. Arguably, Duran had no business fighting above welterweight, so he appeared to have an exceptional ability to take and deliver punishment. Shane Mosley, OTOH, doesn't seem to have carried his punching power from lightweight to welterweight and light middle. He still takes a good punch, as proven against Forrest. But even at welter I think he's at the outer margin of his weight-strength. Roy Jones is a classic example of what happens to an outstanding boxer when the quickness and reflexes deteriorate even slightly. A fraction of a second means the difference between delivering a KO and being deflected by an opponent; and between him being able to dodge a punch and being hit and hurt. Same thing happened to Ali. Ditto Whitaker against Trinidad. He was only slightly slower than a peak Sweet Pea, but that was enough to cost him against a then-top Tito.