Learn more about the impact ultramarathon running has on red blood cells and how it may do more harm than good for the body.

Only one runner, Michael Wardian, a 51-year-old from Arlington, Virginia, holds the record for the fastest time accomplishing ...

Running 170 kilometres over mountainous terrain caused people's red blood cells to accumulate more age-related damage than those of less ambitious athletes ...

Camille Herron, 42, is one of the world's top ultramarathon runners, having set 12 world records and becoming the youngest woman to reach 100,000 lifetime running miles. But now, the American athlete ...

Stephanie Case won an ultramarathon race in Wales, running more than 60 miles over rough terrain — and stopping three times to breastfeed her 6-month-old baby, Pepper. In the sport of ultrarunning, ...

His fitness levels match those of healthy men in their 20s.

For the Bull to Bell run, Chiu's toughest stretch was the roughly 30-mile trek along Route 1 in New Jersey from New Brunswick ...

Discover what ultramarathon runners eat to run 100 miles. This ultra runner enjoys avocados and bison bars, and follows a ...