100 Metres Hurdles

Athletes run in lanes and start from blocks, negotiating 10 hurdles of 2ft 9in (83.8cm) over a distance of 100m.

A reaction time – measured by sensors in the starting pistol and on the blocks – of less than 0.1 is deemed a false start and runners will be recalled, with the responsible athlete disqualified.

Once the race is under way, there is 13m to the first hurdle, 8.5m between hurdles thereafter, and 10.5m from the final hurdle to the finish.

The hurdles are knocked down easily if touched, which allows the athlete to continue the race even if she collides with them. A runner can be disqualified if she steps out of her designated lane. The finishing order is determined on time.

At major championships, the women’s 100m hurdles format typically consists of heats, semifinals and final.

The event demands speed, explosive power, agility and precision.