It's a well-accepted approach in sports that the fastest way to a finish line is with negative splits—i.e. to get faster as the race progresses. In the ultrarunning community, this approach more resembles a sacred mantra than a mere guideline.
South Africa's Comrades Marathon is the granddaddy of ultramarathons, having been held first in 1921 and nearly every year since inviting runners to traverse the 56 miles between Durban and Pietermaritzburg. This year runners were also invited to avoid spectators fleeing an out-of-control automobile.
After 99.75 miles and more than 16 hours of running, Thomas Lorblanchet comes striding slowly down 6th Street in Leadville, Colo. It's almost 9 on an August night, and as he crests a small hill, his way is lit only by his headlamp and the glowing light from the one-story houses that line the street. His strides are…