After signing with Fila Skyrunners in 1993, he won either thirteen or fifteen of the seventeen high altitude marathons he entered, setting records at both (with a time of 2:52:57) and (a time of 3:22:25). Later in his career he moved to ultrarunning, and sustained his previous success, setting course records in the San Juan Solstice 50-mile race in Lake City, Colorado in 2004, and breaking the record for the Leadville Trail 100 race in 2005 by over an hour and a half.