Ultra distances include races that last for specific time periods, where runners try to cover the greatest possible distance within that time. These races can be:

6-hour races: Runners have six hours to run as far as they can. These are often held on circular or repeated courses, providing a test of endurance and strategy.

12-hour races: Similar to the 6-hour races, runners attempt to cover the greatest distance within 12 hours. This duration requires careful management of energy and nutrition.

24-hour races: Runners run for an entire 24 hours, trying to cover as many kilometers as possible. These races push the limits of human endurance, discipline, and strategic management of time and resources.

48-hour races: One of the most extreme forms of running, where runners have 48 hours to run. This duration not only requires physical endurance but also incredible mental strength, as well as careful planning for sleep, nutrition, and rest during the race.

All these races offer a platform for runners to explore their limits, build their endurance, and test different energy management strategies within various time frames.