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We did our project on the biomechanical breakdown of the quarterback pass. The quarterback is the leader of a football team, a group of 50 to a 100 people, and he is constantly looked upon for leadership and performance. With these expectations comes great pressure. You have the weight of the whole team on your shoulders, and how you perform affects a lot of people. Another type of pressure is the defense constantly coming to crush you. Some players can deal with the pressure and for some it’s just to much. Keep that in mind when reading this paper, the QB has to perform while under these levels of pressure. The objective of the quarterback pass is to throw an accurate well-timed pass to receivers as they run their designated routes. To accomplish this, the quarterback must employ sharp mechanics to deliver the ball with proper velocity, timing and precision. Special considerations would be the shape of the football, which is officially called “Prolate Spheriod”. This is especially unique shape because it is not perfectly round and if the ball is thrown sideways it will not go as far, as there will be tremendous drag. However, when thrown properly with the nose forward the ball cuts through the air, the drag is reduced, and it travels great distance. In addition, the spin that a quarterback puts on the ball makes it a gyroscope and increases the stability and accuracy of the pass. Your hand placement while preparing to throw is important. The best way to hold the ball is towards the back or end of the ball and you want your pinky and ring finger on the laces while your other fingers grip the end of the ball. Accuracy is improved by having proper technique. Proper technique is while holding the ball in the cock back position, having the ball chest to ear high before release to increase speed of release. Keeping eyes downfield and shoulders parallel to him and your pivot foot pointing at your receiver. Throw the ball in a half circle 180 degree rotation to increase the centrifugal force and causes the ball to be launched at a greater velocity. Be sure to shift your weight evenly at your release to ensure a powerful delivery of the football. The rotation of your shoulders when throwing the football will generate torque that will help maximize velocity on the ball. The ideal release point for the football is at about three quarter of the way through your half circle motion. You need to bring your throwing hand thumb to point to the ground after your release to help impart spin on the football and ensure accuracy through follow through. There are three simple steps or phases to the skill of throwing the football. They are the setup, delivery, and follow through which occur in the Sagital plane. The setup phase the quarterback holds the ball at chest to ear level, gripping with both hands, cocking back with non-throwing shoulder pointed at intended receiver. There are flexion at the elbow joint, abduction of the shoulder and rotation of the shoulder. In the delivery phase weight is shifted from back foot to front foot, arm swings forward in a half circle, and ball is released of the tip of your index finger to create spiral and proper trajectory on your throw. Extension of the elbow joint, pronation of the wrist, protraction of the shoulder girdle on throwing arm side. Torque is highest in this phase created from your core to create velocity on average of 55 to 60mph. In the last phase, the follow through you keep moving your weight to your front foot. Your back foot will naturally lift of the ground, and rotate your upper body around. Let your throwing arm swing down and across your body. Your hand should end up around the pants pocket on the opposite side of your body with your thumb down. Also you want to step through with back leg to ensure power and decrease risk of injury. Adduction of the shoulder, flexion of the elbow joint, pronation of wrist and hip rotation occurs in this phase. With all these ideals, and proper techniques we have to keep in mind that we are playing football. The QB is constantly being physically pursued by the defense. The defense is trying to mentally confuse the QB as well. So on every passing play were the QB is asked to complete a pass he is dealing with not only the rush by the Defensive linemen and the coverage of the defenders in the Secondary, and he must mentally recognize what coverage the defense is in and find the open receiver. Another thing that a QB must recognize is what receiver he is throwing to. Receivers differ in not only size and speed but also ability’s, and a responsible QB will know and be aware of who he is throwing to. So at times quarterbacks might have to throw on the run or off balance, in those cases accuracy and power could drop or be heighted depending on the particular player. Also the QB has to have proper ball placement reacting to the defender, obviously but the ability to recognize and perform the proper throws are difficult. Examples, a back shoulder throw on a “Go” route due to the defenders coverage over the top, or on a slant pattern throwing the ball on target and low to protect the receiver from the big hit. These are aspects of the game that the QB must deal with on a given passing play. Almost every skeletal muscle in your body is important when throwing a football, from your bigger, powerful muscles to your postural stabilization muscles to your fine motor movements. Your abdomen is one of the most important groups of muscles, because it’s your center of gravity where torque creates velocity to power the pass down the field. The other muscle group is the rotator cuff, which consists of the shoulder muscles, including the supraspinatus, infraspinatus, teres minor and subscapularis muscles and their associated tendons. The most common shoulder injuries associated with throwing the football is injuries to the Ulnar Collateral Ligament (UCL) and Acromioclavicular Joint (AC). Due to over use and fatigue, or improper side arm release, that has been shown to create injuries. Exercises that can lessen the chance of injuries is muscle training to the shoulder for not only power but aerobic fitness as well to have a condition arm for throwing 100’s of balls at one day of practice. Exercises to help with your power you would think would be arm exercises but they are core, abdomen and back are the primary producers of torque that creates velocity, which is speed and power. Another muscle group that creates a lot of power is the lower body. Naturally strengthening every part of your body will decrease the chance of injury. The QB must complete passes with accuracy and velocity through proper technique, dealing with the defense, using all muscle groups but especially the abdomen and the shoulder groups. Creating power through torque from your center of gravity that energy travels through joints and sockets until release. The Quarterback Pass Movement Skill Analysis Jamarcus Walker Colten Quinabo November 2, 2011 References: “Marie Claire” : How to throw a football; Rachel Bertsche We Play: Basic Throwing Mechanics http://www..livestrong.com/article/357167-proper-mechanics-for-throwing-afootball#/ixzz1fKzfILvN http://www.livestrong.com/article/112128-muscles-used-throw-ball/ http://www.youtube.com/watch?v=tVoqA-LKGb4 http://www.topendsports.com/sport/gridiron/physics.htm