NBA Players Aren't as Short as They Seem

Posted by Ross Pomeroy, Real Clear Science, May 16, 2014

The average NBA player meets a key diagnostic criteria for this disease. Care to guess what it is?

It's Marfan syndrome, a genetic disorder caused by the misfolding of the protein fibrillin-1, which is essential to the formation of elastic fibers in connective tissue. In essence, the bodies of people with Marfan syndrome aren't as compact as they should be.

Those affected by Marfan syndrome are often unusually tall, with long, slender limbs. As such, doctors regularly look at the ratio of a person's wingspan -- the length of the outstretched arms from fingertip to fingertip -- to their height when making a diagnosis. A ratio larger than 1.05 is indicative of Marfan.

According to an analysis completed by Sports Illustrated in 2012, the average NBA player has a wingspan-to-height ration of 1.063. While most of them probably don't have Marfan syndrome, there's little doubt that they are absurdly long and lanky. In effect, this makes NBA players both wider and taller than they really are.

You might recall Leonardo da Vinci's iconic painting of the Vitruvian Man, which accurately depicts the idealized proportions of a human male.

"Leonardo da Vinci's Vitruvian Man has an arm span equal to his height. So do I. So, probably, do you," David Epstein, a senior writer at Sports Illustrated, wrote in his 2013 book The Sports Gene.

(More here.)