Hurdling
Hurdling is the act of running and stepping over an obstacle at speed. In the sport of athletics, hurdling forms the basis of a number track and field events which are a highly specialized form of obstacle racing. In these events, a series of barriers known as hurdles are set at precisely measured heights and distances which each athlete must pass by running over. Failure to pass over, by passing under, or intentionally knocking over hurdles will result in disqualification.
Accidental knocking over of hurdles is not cause for disqualification, but the hurdles are weighted to make doing so disadvantageous.
The most prominent hurdles events are 110 meters hurdles for men, 100 meters hurdles for women, and 400 meters hurdles (both sexes) – these three distances are all contested at the Summer Olympics and the World Championships in Athletics. The two shorter distances take place on the straight of a running track, while the 400 m version covers one whole lap of a standard oval track. Events over shorter distances are also commonly held at indoor track and field events, ranging from 50 meters hurdles upwards. Women historically competed in the 80 meters hurdles at the Olympics in the mid-20th century. Hurdles race are also part of combined events contests, including the decathlon and heptathlon.