SAN FRANCISCO, CA - DECEMBER 04:  A runner climbs a ladder to get up a boulder during the GORE-TEX 50 Mile Race in The North Face Endurance Challenge on December 4, 2010 in San Francisco, California. The 50 mile race began in the dark at 5am in the Marin Headlands just north of San Francisco. The course was a mix of fire roads and single track, with a majority of it having views of the Pacific Ocean.  (Photo by Ezra Shaw/Getty Images)