With Monday's announcement of a marathon relay race to be run within Sunday's New York City Marathon, featuring pro basketball personalities, it now can be told: NBA commissioner Adam Silver did not play organized basketball growing up; he was a track and cross-country athlete.

"Yes," Silver confirmed at a midtown luncheon with marathon director Mary Wittenberg. "I played basketball recreationally. I did not play basketball for my high school team [in Rye]. I ran the 400 [meters] and half-mile, and I ran on the mile relay, too."

At 52, he still runs regularly, four or five times a week, and Sunday he will be the first of 24 familiar names from the hoops world participating in the baton pass from Staten Island to Central Park.

Silver will run the farthest among the group, not quite three miles across the Verrazano-Narrows Bridge. The rest -- including former Knicks Bernard King and Allan Houston, former Nets Darryl Dawkins and Jason Collins, former WNBA star Teresa Edwards, former NBA referee Bob Delaney and current Knicks play-by-play man Mike Breen -- will put in about a mile apiece, with 7-2, eight-time All-Star Dikembe Mutombo, noted for putting a stop to opponents' field-goal attempts, taking the final steps in Central Park.

And possibly adding his famous finger wag in celebration.

The NBA-Marathon partnership is meant to highlight the importance of physical activity and promote healthy lifestyles from children and families. Each basketball celebrity will run with a student from the New York Road Runners' free, year-round youth running programs.

Silver called it a logical confluence of two sports "with a lot in common. Both require a lot of running and being physically fit."

Twice, Silver has completed the full marathon, in 2002 and 2010, both times in slightly less than four hours, which easily would put him in the top third among the expected 50,000 runners. He said he initially felt "a little awkward" not to be going the full distance.

But both the fitness initiative, and the publicity tie-in with the NBA's plans for its February All-Star activities in two of the city's five boroughs, connect nicely with the marathon's five-borough push for kids' programs.

"I've been a runner, really, my whole life," Silver said. "It's been part of my daily life forever." He runs around the reservoir in Central Park, near his Upper West Side home, and on treadmills when traveling. During a recent trip to China, he said he joined several dozen workers from Beijing's NBA office in a run through the city's main park.

Sunday, at the completion of his relay leg, he will hand off to former St. John's star Chris Mullin.

"In high school, when I ran the mile relay, we spent a lot of time on not dropping the baton," Silver said. "I'm worried about Chris Mullin's hands."