U.S. marathon runner Meb Keflezighi trains for the London 2012 Olympics in Mammoth Lakes, California May 30, 2012. Olympic silver medalist Keflezighi, 37, is the oldest American ever to qualify for the Olympic marathon. He trains at an altitude of around 9,000 feet in Mammoth to increase his red blood cells and boost his endurance.
Olympians in training
Athletes around the world, from the smallest countries to the richest nations, train for the upcoming 2012 London Olympics.