Download QuarterBackPas

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