the final is credited with their longest throw, regardless of whether it was achieved in the preliminary or final three rounds. The competitor with the longest legal put is declared the winner. Weight In open competitions the men's shot weighs , and the women's shot weighs . Junior, school, and masters competitions often use different weights of shots, typically below the weights of those used in open competitions; the individual rules for each competition should be consulted in order to determine the correct weights to be used. Putting styles Two putting styles are in current general use by shot put competitors: the glide and the spin. With all putting styles, the goal is to release the shot with maximum forward velocity at an angle of slightly less than forty-five degrees. Glide The origin of this technique dates to 1951, when Parry O'Brien from the United States invented a technique that involved the putter facing backwards, rotating 180 degrees across the circle, and then tossing the shot. Unlike spin this technique is a linear movement. With this technique, a right-hand thrower would begin facing the rear of the circle. They would typically adopt a specific type of crouch, involving their bent right leg, in order to begin the throw from a more beneficial posture whilst also isometrically preloading their muscles. The positioning of their bodyweight over their bent leg, which pushes upwards with equal force, generates a preparatory isometric press. The force generated by this press will be channelled into the subsequent throw making it more powerful. To initiate the throw they kick to the front with the left leg, while pushing off forcefully with the right. As the thrower crosses the circle, the hips twist toward the front, the left arm is swung out then pulled back tight, followed by the shoulders, and they then strike in a putting motion with their right arm. The key is to move quickly across the circle with as little air under the feet as possible, hence the name 'glide'. Spin This is also known as the rotational technique. It was first practiced in Europe in the 1950s but did not receive much attention until the 1970s. In 1972 Aleksandr Baryshnikov set his first USSR record using a new putting style, the spin ("круговой мах" in Russian), invented by his coach Viktor Alexeyev. The spin involves rotating like a discus thrower and using rotational