110m - 100m hurdles: the sport

The 110 metre hurdles are an Olympic track athletics discipline run by men. As part of a sprinting event, ten hurdles of 1.067 metres (3.5 ft) in height are placed evenly spaced along a straight course of 110 metres. They are positioned so that they will fall over if bumped into by the runner. Fallen hurdles do not carry a time penalty for the runners, yet they have a significant pull-over weight which slows down the run. Like the 100 metres sprint, the 110 metre hurdles begins in the starting blocks.
For the 110 metre hurdles, the first hurdle is placed after a run up of 13.72 metres (45 ft) from the starting line. The next nine hurdles are set at a distance of 9.14 metres (30 ft) from each other, and the home stretch from the last hurdle to the finish line is 14.02 metres (46 ft) long.
Hurdles athletes are first of all sprinters. They must possess the characteristics of speed specialists - reflexes, power and strength. To this must be added the right physique - hurdlers should be tall, or have proportionally long legs to ease hurdle clearance - and have a flawless hurdling technique. It is a question of flowing over the 10 hurdles like a big cat, without breaking stride. Hurdlers must search for fluidity after the start and for rhythmic speed between hurdles. The 10 jumps must be accomplished with perfect linear movement and style is king.
The Olympic Games have included the 110 metre hurdles in its program since 1896. The equivalent hurdles race for women was run over a course of 80 metres from 1932 through 1968. Starting with the 1972 Summer Olympics, the women's race was set at 100 metres.
The first great hurdler was Alvin Kraenzlein (USA), who created a new technique by striding over the hurdles and taking three steps between barriers. This style was further refined in 1920 by the Canadian Earl Thomson who became the first hurdler under 15 seconds.
The world record stands at 12.87 seconds, set by Dayron Robles of Cuba in June 2008 at the Golden Spike meet in Ostrava (Slovakia).
In hurdle sprinting, style is king and though many athletes rely on raw speed, proper technique and well-planned steps leading up to and between each hurdle will allow an efficient hurdler to outrun faster opponents. This applies to all hurdles races, men's and women's.
When approaching the first hurdle, one does not want to stutter-step (a term used to refer to the cutting of your stride length before reaching a hurdle). This cuts the runner's momentum and costs valuable time. One should attack the hurdle by launching at the hurdle from 6-7 feet away (depending on runner's closing speed.) The lead leg should be extended yet slightly bent (because a straight leg leads to more time over the hurdle) so that the heel just narrowly clears the barrier's height. After launching, the trail leg is tucked in horizontally and flat, close to the side of the hip. The runner should feel as if he/she is narrowly avoiding knocking each hurdle down with his/her heel. The objective is to minimize center-of-gravity deviation from normal sprinting and reduce time spent flying through the air. All effort should be made to land light on one's feet and carry maximum momentum going to the next hurdle or finish line.
In order to properly hurdle over an obstacle and not simply jump over it, a runner must adjust his or her hips to raise them over the hurdles. Upon crossing over the hurdle barrier, the runner's lead leg should snap down quickly landing roughly 3-feet (1m) beyond the hurdle. The trail leg should drive forward at the knee (not swing - swinging causes the trunk to straighten up), and pull through to maintain stride length.
In men's hurdles it is usually necessary to straighten the leg at the top of the flight path over the hurdle, however a partial bend in the knee gains a faster push off when you hit the ground. The ability to do this will depend on the runners's leg length. As soon as the foot has cleared the hurdle, the knee starts bending again to lessen the effect of a long, slow pendulum. In women's hurdles, the lead leg is usually straight and the center of gravity does not rise relative to a normal running stride. Another way to view it is the foot path: "shortest path up and shortest path down". The opposite arm reaches farther forward and the elbow travels out to the side and then behind to make room for the trailing leg. The trailing leg also leads with the knee, but the foot and knee is horizontal, tucked up as tight as possible into the armpit.
As soon as the lead leg touches down, a strong downward push is exerted to enable the trailing leg's knee to come up under the armpit and in front of the chest. This enables recovery of some of the energy expended in the flight.
The choice of lead leg depends on personal preference. Some people do not know their lead leg so the best way to determine this is to have somebody push you from behind and see what leg you step forward with. This is your lead leg. Sprint hurdlers often measure the steps between hurdles such that every hurdle is taken with the same lead leg.
This article is licensed under the GNU Free Documentation License. It uses material from the article "110m hurdles" at  http://en.wikipedia.org/wiki/110m_hurdles