Discus Throw - Description

Description

The discus, the object to be thrown, is a heavy lenticular disc with a weight of 2 kilograms (4.4 lb) and diameter of 219–221 millimetres (8.6–8.7 in) for the men's event, and a weight of 1 kilogram (2.2 lb) and diameter of 180–182 millimetres (7.1–7.2 in) for the women's event.

Under IAAF (international) rules, Youth boys (16–17 years) throw the 1.5 kg discus, the Junior men (18–19 years) throw the unique 1.75 kg discus, and the girls/women of those ages throw the 1 kg discus.

In international competition, men throw the 2 kg discus through age 49. The 1.5 kg discus is thrown by ages 50–59, and men age 60 and beyond throw the 1 kg discus. Women throw the 1 kg discus through age 74. Starting with age 75, women throw the 750 gram discus.

The typical discus has sides made of plastic, wood, fiberglass, carbon fiber or metal with a metal rim and a metal core to attain the weight. The rim must be smooth, with no roughness or finger holds. A discus with more weight in the rim produces greater angular momentum for any given spin rate, and thus more stability, although it is more difficult to throw. However, a higher rim weight, if thrown correctly, can lead to a farther throw. A solid rubber discus is sometimes used (see In the United States).

To make a throw, the competitor starts in a circle of 2.5 metres (8 ft 2 in) diameter, which is recessed in a concrete pad by 20 mm. The thrower typically takes an initial stance facing away from the direction of the throw. He then spins counter-clockwise (for right-handers) around one and a half times through the circle to build momentum, then releases his throw. The discus must land within a 34.92-degree sector. The rules of competition for discus are virtually identical to those of shot put, except that the circle is larger, a stop board is not used and there are no form rules concerning how the discus is to be thrown.

The distance from the front edge of the circle to where the discus has landed is measured, and distances are rounded down to the nearest centimetre. The competitor's best throw from the allocated number of throws, typically three to six, is recorded, and the competitor who legally throws the discus the farthest is declared the winner. Ties are broken by determining which thrower has the longer second-best throw.

The basic motion is a forehanded sidearm movement. The discus is spun off the index finger or the middle finger of the throwing hand. In flight the disc spins clockwise when viewed from above for a right-handed thrower, and counter-clockwise for a lefty. As well as achieving maximum momentum in the discus on throwing, the discus' distance is also determined by the trajectory the thrower imparts, as well as the aerodynamic behavior of the discus. Generally, throws into a moderate headwind achieve the maximum distance. Also, a faster-spinning discus imparts greater gyroscopic stability. The technique of discus throwing is quite difficult to master and needs lots of experience to get right, thus most top throwers are 30 years old or more.