Scissors-Jump
The scissors is a style used in the athletics event of high jump.
As it allows jumpers to land on their feet, it is the style most often used by junior athletes where the landing surface is not deep or soft enough to meet full competition standards.
The approach (or run-up) in the scissors is a straight line at 30 to 50 degrees to the bar, jumping over the lowest point of the bar which is usually the centre. Speed is brisk, simply to ensure horizontal travel over the bar, but not a full out sprint, as there is little chance to resolve forward motion into vertical motion at take-off. Horizontal acceleration should be complete by take-off, with the shoulders held high and the take-off leg (the outside leg in the case of the scissors style) flexing to launch the jumper into the air.
At take-off the leg nearer the bar (the lead leg) is held straight and swung into the air to clear the bar. At exactly the same time the hips and body are driven into the air by the take-off leg. As the jumper crosses the bar, the trailing or take-off leg has to be quickly swung up to clear the bar. If this occurs as the lead leg crosses and clears the bar, the lead leg can be driven downwards, helping to keep the athlete's centre of mass closer to the bar (in other words, enabling clearance of a higher bar). This up-down/up movement of the legs can best be described as a scissoring action.
Once the take-off leg has left the ground (but not before) the athlete should attempt to pull the upper body face down towards the knee, also to keep the centre of mass as close as possible to the bar. Care must be taken not to hit the head against the knee.
Driving or swinging the arms into the air at take-off provides additional upwards momentum. The arms can be brought back to the sides during clearance, as a further measure to keep the centre of mass as close as possible to the bar. Even with these measures, it is clear that the bar remains considerably below the centre of mass, so the scissors is far from an optimal clearance technique. Landing from the scissors is usually on the feet, but a landing area of soft matting or sand is desirable to reduce foot impact.
Until the invention of the eastern cut-off by Michael Sweeney in the 1890s, high jumpers used fairly primitive variants of the basic scissors style. One of the most eminent of these early jumpers was Marshall Brooks of Oxford University, who achieved the first jump of 6 ft (1.83 m) on 17 March 1876. A few weeks later he improved this mark to 6 ft 2 1⁄2 inches (1.89 m). This record stood until 1880 when Patrick Davin of Ireland jumped 6 ft 2 3⁄4 inches (1.90 m). These jumpers ran straight at the bar in a style not unlike long-jumping with legs and hips lifted. Indeed, Davin was also holder of the world long jump record. The next world record in high jump was perhaps the first achieved with a true scissors style.
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