Interesting read by Epstein.
It's in last week's SI. The picture that accompanies it is quite humorous (it's of AD)
Most people do indeed have a wingspan approximately equal to their height. But an analysis of measurements from NBA predraft combines—where players are measured without shoes—for my forthcoming book The Sports Gene shows that the average ratio of arms to height in the NBA is an astounding 1.06. (To put that in context, a ratio of greater than 1.05 is one of the diagnostic criteria for Marfan syndrome, a disorder of the body's connective tissues that often results in elongated limbs.) Thus, an average NBA player, who stands about 6'7", has a wingspan of seven feet.
Certainly it doesn't take statistical analysis to conclude that NBA players are freakishly tall. (Although some stats help put the freakishness into perspective: Seven-footers are routine in the NBA but so rare in the rest of the country that of American men ages 20 to 40 who stand seven feet tall, an estimated 17% are in the NBA right now, according to analysis of data from the NBA and the Centers for Disease Control.) But NBA players are also outlandishly long—even the "short" ones. At 6'2¾", Wizards guard John Wall might not be able to see the very top shelf at the grocery store, but with 6'9¼" worth of arms, no doubt he can reach it.
Anthony Davis, who was taken first overall by the Hornets in the 2012 draft, is 6'9¼" with a 7'5½" wingspan. A player with such a build will get at least 10 more blocks per season than a giant who is 7'1" but who, like most of humanity, has arms that only match his height. "He knows he can block shots while backing up because he can come over the top with those long arms," says Rockets rookie Terrence Jones, who played with Davis at Kentucky and had a jumper swatted by him less than 30 seconds into their first NBA matchup, on Oct. 24. "In practice we always knew we had to do something extra to get a shot over him."