Hurdling is a
track and field event. In it, runners jump over several 'hurdles' which are wood obstacles that are about 1 meter high. Generally, the hurdles are designed to safely fall over if the runner misses them. Every now and then however, a hurdler will trip over the hurdles and wipe out.
Hurdling events usually come in 50, 100, 110 or 400 meter distances.