Ryan Hall

Having attracted widespread attention in the running world since he was a standout at Big Bear (Calif.) High School, Hall is perhaps the great American hope for a medal in the marathon, especially after running a 2:04:58 to take fourth place in the 2011 Boston Marathon. That would easily be an American record, although it does not qualify because Boston is a point-to-point course with an elevation drop. Hall does officially hold the U.S. record in the half marathon, becoming the first American to break one hour at 59:43. That's a highlight of an impressive career, which includes a 10th-place finish at the Olympic marathon in Beijing after he won the Olympic Trials Marathon before those Games. He earned his spot in London by finishing second to Meb Keflezighi in Houston in January. Hall is familiar with running in England, having made his marathon debut in 2007 at the London Marathon, then taking fifth place at the same event a year later in 2:06:17, a personal best at the time. Hall ran in college at Stanford, where he won the 2005 NCAA 5,000m title and met his wife Sara (formerly Bei), also a runner and an Olympic hopeful.