Get the blood flowing
U.S. Air Force Airman 1st Class Adam Orton, 74th Aircraft Maintenance Unit aerospace propulsion journeyman, performs high-intensity step-ups during a workout at Moody Air Force Base, Ga., Aug. 9, 2012. After 30 hours of continuous racing, sleep deprivation, dehydration, bleeding feet and total exhaustion, Orton dropped out of the race. Typically, only 10 percent of the competitors finish the race. (U.S. Air Force photo by Airman 1st Class Jarrod Grammel/Released)