The event

Of all the eight disciplines in the Games, endurance riding is probably the simplest for the average sports fan to understand. It's basically a long-distance race — much like cross-country running — but over great distance and, of course, on a horse. To be successful, the competitor must have knowledge of pace, and be safe and efficient in the use of his or her horse across country. The competition is against the clock and, at the elite level, over a distance of 100 miles.

How it's scored

The competitor who finishes in the shortest time wins. Posting a time is not quite that simple, though. The race is divided into phases — at least five. After each phase, veterinarians check the horses' fitness and ability to continue. A fit horse that is also able to demonstrate quick recovery gives the rider a distinct advantage, reducing the time spent in the inspection area.

What to watch

Spectators will not be able to see much of the endurance course, as the 100-mile test stretches outside the Kentucky Horse Park, but be assured that the natural obstacles are many, including creeks, ditches and woods. The task is daunting. At the 2006 Games in Aachen, Germany, 65 entrants completed the course, and 94 did not. The competition begins at 7 a.m. but won't end until evening. The winning time in Aachen was nine hours, 12 minutes, 27 seconds. The final finisher crossed the line after more than 13 hours.

Spectator etiquette

The most important thing to know is that no spectators are allowed off the Horse Park property to view the event. Cheering is discouraged during vet checks but is OK otherwise as long as it's not distracting to athletes or horses.

Fast facts

■ If a horse becomes fatigued, the rider may choose to dismount and walk or jog with the horse. However, riders must be mounted when they cross the start and finish lines.

■ Any breed of horse is allowed to compete, but the Arabian tends to dominate the top levels because of the breed's stamina and natural endurance abilities.

■ Before the race, all horses are inspected by a veterinarian to ensure their fitness. The rider is briefed about the trail and provided with a map that shows the vet checkpoints and natural obstacles.

■ Since the first world championships in 1986, USA Endurance has won seven individual and two team gold medals.

Participants

Countries competing (based on preliminary nominations): 26 countries have endurance teams; six countries will be represented by individuals.

Individuals competing: 162 athletes have been nominated to compete in endurance.

Awards: Medals and trophies will be presented to the winning country's team and to the individual champion.

MARK MALONEY, mmaloney@herald-leader.com

Team and individual competition, 7 a.m.