In his Frontal Cortex blog at Wired.com, science writer Jonah Lehrer discusses possible reasons for why small towns and cities (fewer than 500,000 people) produce a significantly greater percentage of professional athletes than larger cities.

“While approximately 52 percent of the United States population resides in metropolitan areas with more than 500,000 people, such cities only produce 13% of the players in the NHL, 29% of the players in the NBA, 15% of the players in MLB, and 13% of players in the PGA,” Lehrer writes.

The Canadian psychologists who uncovered those statistics offer one explanation:

But Lehrer, citing University of Chicago psychologist Sian Beilock, whose book “Choke” is soon to be published, suggests an additional possibility:

Psychologically, the kids risk burnout, Beilock says. And, physically, they risk sports-related injuries that may, ironically, end their athletic career.

“This is a nice addendum to the 10,000 hour rule [the idea that people need to spend about 10,000 hours of practice before they become an expert],” writes Lehrer. “While deliberate practice remains absolutely crucial, it’s important to remember that the most important skills we develop at an early age are not domain specific. (In other words, Tiger Woods is not using the same golf swing he relied on as a 5 year old.) Instead, the real importance of early childhood has to do with the development of general cognitive and non-cognitive traits, such as self-control, patience, grit, and the willingness to practice.”

You can read Lehrer’s entire column here.