Shotput

The shot put is an athletics (track and field) event involving "putting" (throwing in a pushing motion) a heavy metal ball (called the shot) as far as possible.

It is common to use the term "shot put" to refer to both the shot itself and to the throwing motion.

Competitors take their throw from inside a circle 7 feet (2.135 meters) in diameter, with a toe board approximately 10 cm (4") high at the front of the circle. The distance thrown is measured from the inside of the circumference of the circle to where the shot lands at its nearest disturbance of the soil.

* The athlete must rest the shot close to the neck and keep it tight to the neck while throwing.
* At the end of the throw, the thrower must push the throwing arm straight from the neck, pushing the ball off the fingertips. (If the thrower does not push the ball out and throws it like a baseball, the thrower may sustain a shoulder or neck injury.)[citation needed]

Foul throws occur when an athlete:

* Does not exit from the rear half of the circle, Stepping out of the front is known as a scratch.
* Touches the top of the toe board, the top of the iron ring or outside the circle after having entered the circle and before the judge calls the mark.
* Throws a shot which falls outside the throwing sector to the left or the right.
* Allows the shot to drop below his shoulder or outside the vertical plane of his shoulder during the put.
* Does not pause or demonstrate control after entering the circle and before beginning the throw.
* Takes longer than 90.00 seconds to perform the throw attempt.

Each competitor receives a certain number of throws, usually 6 in elite competition, and the competitor with the farthest legal put is declared the winner. In men's competition, the shot weighs 7.26 kilograms (16 pounds). The women's shot weighs 4 kg (8.8 pounds). American high schools usually use 12 pound (5.44 kg) shots for boys and 4 kg shots for girls; these are sometimes used as practice shots as well. The weight of the ball differs depending on the age group. Men over the age of 50 use a 6 kg shot (13.2 pounds).

Shot put competitions have been held at the Summer Olympic Games since their inception, and is also included as an event in the indoor world championships. The shot put originates from Highland games 'stone put' where Scottish people put a rounded cube, stone, or metal form of considerable weight from behind a given line.[citation needed]

Two putting styles are in current general use by shot put competitors: the glide and the spin.

The origin of the glide dates to 1951, when Parry O'Brien of the United States invented a technique that involves the putter facing backwards, rotating 180 degrees across the circle, and then tossing the shot. With this technique, a right-hand thrower begins facing the rear of the circle and kicks to the front with the left leg while pushing off forcefully with the right. The key is to move quickly across the circle with as little air under the feet as possible, hence the name "glide". As the thrower crosses the circle, the hips twist toward the front, followed by the shoulders and strikes in a putting motion with their arm.

The spin was invented in the United States in 1976. From this, in 1976, Brian Oldfield popularized the spin technique which involves rotating like a discus thrower and using rotational momentum for power. Oldfeld set the record of 75 feet (22.86 m) in 1975; it was unofficial, however, because he was a professional at a time when the IAAF had an amateur-only policy, but undisputed and over 3 feet better than the official world record at the time. Oldfield's record in the 33 years since has been bettered by only 10 inches. In the spin, a right-handed thrower faces the rear, and begins to spin on the ball of the left foot. The thrower comes around and faces the front of the circle and drives the right foot into the middle of the circle. Finally, the thrower reaches for the front of the circle with the left foot, twists his hips and shoulders like in the glide, and puts the shot.

With all putting styles, the goal is to release the shot with maximum forward velocity at an angle of approximately forty degrees. Currently, most top male shot putters use the spin, but the glide remains popular, especially at the amateur level and among women, since the technique breeds higher consistency for the athlete as opposed to the rotational technique. It is worth noting that the world record by a male putter (Randy Barnes) was completed with the spin technique, while the close second-best all-time distance (Ulf Timmermann) was completed with the glide technique. Measuring which technique can provide the most potential is difficult, as many of the best throws recorded with each technique come from athletes under a thick cloud of doping suspicion and violations. In some opinions the decision to glide or spin should be based on the thrower's size and power, with short throwers benefiting from the spin and taller throwers benefiting from the glide, but for many throwers selecting the right technique differs on an individual basis, with almost all throwers first developing the glide technique.