The biggest shift in the evolution of the NFL has been the modern-day emphasis on passing instead of running. The second-biggest shift in the evolution of the NFL is even more tangible: players have gotten truly enormous.
This chart, created by WNYC data journalist Noah Veltman, shows how big the transformation has been:
In the early days, many players were large but still within the range of normal humans — around 200 pounds, and 6 feet tall. Today, the average player is now around 250 pounds, and 6’2" or so. The blob that forms at the top-right around the year 1995 or so is made up of today’s offensive linemen and defensive tackles, who are virtually all above 300 pounds and average about 6’4".
To read more, check out 40 maps and charts that explain sports in America.