Median age: 47 (for the Umstead 100; the oldest runner was 71).

By sex: 70.6 percent male, 29.4 percent female (based on the 14,251 people who finished an ultra in 2007).

For the Umstead 100, the 234 runners came from Germany and Sweden and 32 states, including Alaska and Hawaii. Forty runners were from the Triangle. ("This park [Umstead] being here encourages a lot of trail running," says assistant race director Joe Lugiano.

What food keeps the runners going for 100 miles? You could find energy gels and power bars at the Umstead 100 aid stations. But here's what dominated the buffet: hard boiled eggs, baked potatoes, sweet tea, pizza, chicken breasts, candy, hot dogs, pretzel sticks, danish, coffee, peanuts, animal crackers, potato soup.

What's a "pacer"? Beginning with Lap 5 or past 6 p.m. Saturday, whichever came first, Umstead 100 participants were allowed to pick up a fresh runner to accompany them. Faster runners use pacers to help maintain a brisk pace; others like them for psychological support and for someone to talk to. Some pacers were training partners of the runners; 30 were supplied by the N.C. Roadrunners Club,

Belt buckles? At the Umstead 100, first-time finishers of a 100-mile race received a bronze belt buckle; first-time finishers under 24 hours received a silver belt buckle. The belt buckle, explains Lugiano, is symbolic of the days when winners of endurance horseback races received a belt buckle.

Calories burned running 100 miles? A 150-pound person running 4 mph covering 100 miles would burn 8,693 calories, according to the Fitness Partner's Activity Calculator (www.primusweb.com)

More info: The Umstead 100 Endurance Run's site is www.umstead100.org. For information about ultramarathons: http://planetultramarathon.wordpress.com.

Read more on the Get Out! Get Fit! blog: http://blogs.newsobserver.com/joemiller.