A sport in which a competitor, traveling on foot, must overcome various physical challenges that are in the form of obstacles. Mud and trail runs are combined and the races are designed to result in mental and physical collapse. Obstacles can include climbing over walls, carrying heavy objects, traversing bodies of water, crawling under barbed wire, and jumping through fire. Many obstacles are similar to those used in military training, while others are unique to obstacle racing and are employed throughout the course to test endurance, strength, speed and, dexterity. Races vary in both distance and challenge level, combining trail running,road running, and cross country running.