Every NFL player, graphed

This shows every person who's ever played for the NFL going back to 1920. I graphed them height versus weight. And the brighter squares have more people. So, for example, in 1926, there were lots of players who were 5'10" and 190 something pounds. But this darker square is just one guy, Eddie Keenan. 320 lb. He's a total outlier, even though today he wouldn't stand out. The smallest player in the 20s was Jack Sup Shapiro, 5'1, 119 pounds. He played a single season for the Staten Island Stapletons. As we move forward in time, look at this big shift in the 80s and 90s. In 1978, rule changes made passing more effective and protecting the quarterback became more important. Breaking things down by position shows exactly what happened. Here's the 1945 equivalent of offensive linemen and quarterbacks. If you look at the averages, they're pretty close in size. 80 years later, quarterbacks have grown a little, but the linemen have gotten huge. Defensive backs, by comparison, have barely changed. And so the range of body types in the NFL has never been broader and some of the forces involved in collisions have never been higher.