LAKE PLACID, N.Y. (AP) -- United States bobsledder John Napier is leaving the sport and will try to become a member of an elite military unit.

The 25-year-old Napier, a member of the Vermont National Guard as a slider, volunteered for a five-month tour in Afghanistan after competing in the 2010 Vancouver Winter Olympics and was deeply affected by it.

Darrin Steele, chief executive officer of the U.S. Bobsled and Skeleton Federation, says he's disappointed but not surprised. Steele says Napier had "some second thoughts when he first came back. He was trying to figure out if he wanted to go on with the military or jump back into bobsled."

Napier told the U.S. team last week that he was leaving after having been involved in the sport since he was a kid.

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