by Max Mulitz
Studies of the NBA have shown that wingspan is more important than height when predicting blocked shots (and player success in general.) Of the five players on the All NBA team from last season, Kawhi Leonard has remarkably long arms, while Lebron James, Russell Westbrook, and Deandre Jordan also have unusually long arms relative to their height. Only Stephen Curry’s arm length is unexceptional.
It is also true that that the top 3 Pound For Pound Fighters in the UFC, Conor McGregor, Demetrius Johnson, and Jon Jones, all have long arms for their height. At 76 inches tall, Jon Jones 84.5 inch reach is famously the best in the UFC. Mcgregors 74 inch reach at 5’9 is also unusual.
Perhaps the greatest Olympian of all time, Swimmer Michael Phelps, also has abnormally long arms.
At the NFL level arm length and wingspan data can be hard to come by, but it is worth noting that Julio Jones, Deandre Hopkins, and Odell Beckham all have exceptionally long arms for their height. Neither Hopkins nor Beckham are particularly tall for NFL receivers, but both players seem to have enormous catch radii, so it seems reasonable to suspect that their arm length is causing them to be able to play bigger than their height would suggest.
I will build to looking at Arm Length among NFL players, but first I wanted to establish some theory and priors. Across a range of sports, we have evidence that the top performers tend to have unusually long arms relative to their height. It would be very strange if height was more important than arm length/wingspan, especially for receivers and cornerbacks, given the fact that arm length is more important than height when predicting NBA players and the fact that the top performers across a fairly broad range of sports all have unusually long arms for their height.
It’s unclear exactly how height and arm length combine to determine a players “size” or “length”, but it should be clear that any explanation that only uses height at the expense of arm length is inadequate.