Force Vectors SHOT PUT MECHANICS

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1 SHOT PUT MECHANICS The shot put is an individual event that is dominated by big, powerful male and female athletes. There are two techniques for throwing the shot put---the glide and rotation--. Neither technique is necessarily better for High School Students. Generally, stronger athletes tend to do well with the glide technique, and more powerful (fast) athletes tend to do well with the rotation. At Layton High School, we choose to stick with the glide method because of the simplicity of it. If the advanced shot putter wants to experiment with the rotary method, they are welcomed to. It should be noted that the rotary technique has to be performed by a big athlete in the tight confines of a shotput ring---a ring that is only 2.135m (7 ft) in diameter. Additionally, the shot must stay in contact with the putter s neck until the final putting action occurs. Force Vectors Think of an athlete putting a shot at a release angle of about 42 degrees to the horizontal. To give the shot some height, putters must apply some force in the direction. So the putters apply some (but not all) of their force in a vertical direction. To get the shot moving horizontally, they apply force in that direction as well. The combination of horizontal and vertical forces gives the shot it s 42-degree trajectory. During flight the earth s gravitational force pulls the shot directly downward (perpendicularly). Gravity only fights against the vertical force vector that the athlete applied to the shot. Gravity does not influence the horizontal force vector. In addition to the force of gravity, air resistance provides a force that battles the forward motion of the shot. The result of this war of forces determines the distance the shot travels. Additionally, it should be noted that the shot-putters release the shot will above shoulder level, with the shot then landing at ground level. Some shotputters are taller than others, so body type can increase the height of release, giving those athletes an advantage.

2 Preparation for the Glide (Right hand putter): The athlete stands at the rear of the ring with the back toward the direction of the throw. The athlete s weight is on the right leg, and the athlete s line of vision is directly to the rear. The athlete cradles the shot under the chin. The left arm is extended and pointed toward the rear. The shot should be gripped with the thumb and fingers of the hand and cradling it under the chin. Don t let the shot drop down into the palm of your hand.

3 The Glide for the Right Hander: The athlete flexes the right leg and lowers the upper body close to the horizontal in preparation for the backward shift (glide) across the ring. The left leg is kicked forward and then backward, and simultaneously the right leg drives the athlete toward the center of the ring. The upper body stays in it s lowered position. At the end of the glide, the athlete pulls the right leg in under the upper body and places the left foot in position at the front of the circle. The right leg foot should be in it s position under the upper body so that it is at right angles to the direction of throw. At the end of the glide, the upper body is still inclined toward the rear of the ring. The shoulders are held square to the rear of the ring and maintaining the backward lean of the upper body. The Put for the Right Hander: (Putting = Pushing) The athlete begins the final putting action by applying force from the ground up in the following sequence: legs, hips, chest, and throwing arm. The legs extend in a rotary fashion toward the direction of throw. Then the hips rotate in the same direction followed by a forward and upward thrust of the chest. The right side of the body rotates forward and upward around an extended left leg. The elbow of the throwing arm should be kept high, (just below shoulder height) during the put. A powerful extension of the athlete s throwing arm and fingers pushes the shot away from the athlete s neck at approximately 40 degrees from horizontal to complete the throw. The throwing arm should extend in front of the athlete s body with the shot leaving the fingers just above head level. The Reverse for the Right Hander: After the shot has left the athlete s hand, the legs reverse positions. The left leg moves backward

4 from the front of the ring, and the right leg moves forward against the stop board to prevent the athlete from falling out of the front of the ring and fouling the throw. Additional Points to Remember 1. The glide needs to be practiced enough to become one fluid motion to the put. 2. Drive up onto your toes and push forward with your body. Use your whole body in the throw, not just your arms. 3. To obtain the longest distance, a trajectory of about degrees above horizontal is necessary. 4. Use the big muscles of your legs, back, and chest before using your throwing arm, not afterward. 5. Lift upward with your legs and back and simultaneously rotate toward the direction of throw. 6. Keep the elbow of the throwing arm high (just below shoulder height) during the put. 7. Begin the putting action by moving your body forward. Move your hips forward and lift your chest high and square (at right angles) to the direction of throw. 8. Extend your legs and be sure to put the shot from your fingers (not from your palm). 9. Finish the putting action with your throwing arm extended in front of your body and with the shot leaving your hand just above head level. 10. Your backward gliding action is not an upward jump. Don t raise your back or jump up in the air. 11. Keep your feet close to the ground throughout. They should skim across the ground. 12. After extending your right leg, pull it in under you so that it s in a flexed position directly below your upper body. (If you don t do this, your right leg will be unable to provide power for the throw). 13. Keep your upper body low until your glide is complete; then lift upward into the putting action, not before. 14. As soon as you ve completed the glide, think of striking from the ground up by using your legs, hips, chest, throwing arm and fingers in that sequence. Remember that your throwing arm and fingers are the last to act. 15. Make sure your hips and chest move forward beyond your left foot before initiating the reverse. Think of a post extending vertically upward from your left foot. Your body must move past the post

5 before your perform the reverse. 16. Don t perform the reverse before extending your legs fully and driving your body forward into the throw. Standards: Male kg (12lbs) shot Satisfactory = 29 6 ; Good =34 5 ; Excellent = 37 9 Female--4kg (8.81 lbs) shot Satisfactory =21 4 ; Good = 24 7 ; Excellent = 29 6 To Summarize: 1. Stand to the rear of the circle with the back to the throwing area. Both feet are facing to the back of the circle with the left foot near the middle of the ring. 2. Bend forward until the torso is nearly parallel to the ground. Bend the right leg in a partial squat and bring the left foot near the right foot, while keeping most of the body weight on the right foot. 3. Kick the left leg toward the stop board and drive the right foot toward the middle of the circle. 4. Keep the torso low and over the right leg. Pull the right foot to the middle of the circle and quickly assume the power position. The right foot moves counterclockwise almost 90 degrees. The right leg is in a partial squat. The left foot is "in the bucket." 5. Without any hesitation in the middle of the circle, drive the right hip forward and upward, as the torso quickly rises to an upright position and simultaneously turns to the front of the circle. The weight of the body is still over the right leg. 6. As the torso rises to vertical, the body moves over the center of gravity and the weight is over the left leg. Both legs are slightly bent. 7. Drive the shot from the shoulder at a 45 degree angle. Follow through with the arms. Both legs are straightened. Reverse the position of the feet to avoid fouling.