The Mystery of Boxing Weight through Decades

We all know the never ending speculations. Who would have won? Ali or Tyson, Johnson or Marciano, Dempsey or Liston? The never ending story, essentially comparing great heavyweights that eventually never met, considered mostly due to a prime time discrepancy. In this article I'll elaborate the topic, whether such a comparisons are substantial all. Let us start with a table of  some of the most notable heavyweights in the last century with their weight at their prime time: 

Then I'll draw a curve with the weight progression of heavyweights over the years:

On the weight axis I've drawn the weights in lbs starting of 175 pounds, which was and still is the light heavyweight limit and 265 pounds, which is usually the super heavyweight limit in other combats sports (boxing has no such limit but, anyway no great heavyweight was over that limit at his prime). We clearly see a serious increase with the elapsing time. By watching this comparison one can hardly think of Klitschko or Lennox Lewis facing someone at the size of Floyd Patterson or Ezzard Charles - a head smaller, weighting 65 pounds less. History-wise the majority of heavyweights got over 200 pounds somewhere around the late 60s and 70s with Sonny Liston and Muhammad Ali. At that time the lower weight was light heavy, which was as mentioned 175 pounds. The step from 175 to 210, was pretty radical so around the 80s all major boxing regulating organs starting to recognize the so called cruiserweight, which balances the scales at 200 pounds. Nowadays cruiserweight is an established weight division, and there are many heavyweight champions in the recent years, which started from there. However, none of the modern heavyweight great fighters started out of light heavy in contrast to the past, where a lot of heavyweight champions were seeking great matches with light heavyweight champions.

Another huge factor nowadays is the weigh in, which due to promoting and other reasons happens usually around 30 hours before the fight itself. In recent years swallowing up to 20 or even 25 pounds after making the weigh in is a common practice in every championship bout with the purpose of having a weight advantage over the opponent. The plot below shows the weight limits of the corresponding weight class: welter (147), light middle (154), middle (160), super middle (168), light heavy (175) and cruiser (200).

With the orange color I've shown the practice gain of 20-22 pounds. Note that with weight increase the practice gain rises due to the fact of being less percentage of boxers body weight. With red we can see the extreme gain, which some boxers try to make like Chavez Jr. or Victor Ortiz. Often such extreme gains result in a performance drawback, despite being usually a benefit in a boxers early career. Now lets compare both weight plots to compare in which weight class actually would have fit the all time great heavyweights today:

As we can see, it is most likely that today Marciano and Joe Louis would have battled with Gennady Golovkin and Carl Froch, rather than with Klitschko brothers. At this line I'll put this article to rest and will let you make your own conclusions.