"Hurdling is the act of running and jumping over an obstacle at speed. In the early 19th century, hurdlers ran at and jumped over each hurdle, landing on both feet and checking their forward motion. After experimenting with different step patterns the 3-step for high hurdles, 7-step for low hurdles, and 15-step for intermediate hurdles was decided on. 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 caused for disqualification, but the hurdles are weighted to make doing so disadvantageous. Hurdle design improvements were made in 1935, when they developed the L-shaped hurdle. With this shape, the athlete could hit the hurdle and it will tip down, clearing the athlete´s path." - (en.wikipedia.org 11.08.2020)
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