Throwing Arm And Overarm Pattern example essay topic

A baseball pitcher throws a baseball across the plate and the batter hits it to center field, and elderly man pitches horseshoes, a young person spikes a volleyball, student practices driving a golf ball while a college athlete practices punting a football. Once more, as is the case with pushing and pulling, a widely diverse set of activities has a common denominator. Each of these activities involves sequential movement of the body segments resulting in the production of a sum mated velocity at the end of the chain of segments used. The path produced by the end point of this chain of segments is curvilinear in nature. Sequential segmental motions are most frequently used to produce high velocities in external objects. Depending on the objective of the skill, speed, accuracy, distance, or some combination, modifications in the sequential pattern may be involved, larger or smaller ranges of motion might be used, and longer of shorter lever lengths may be chosen.

Regardless of the modifications, the basic nature of the sequential throwing, striking or kicking pattern remains the same. Broker was the first to call attention to the similarity of movement patterns used in seemingly dissimilar activities such as the baseball pitch, the badminton clear, and the tennis serve. Objective evidence of such similarities between throwing and striking activities within each of the three major upper-extremity patterns; overarm, sidearm and underarm. The representative activities from these categories across throwing patterns also showed great similarity in the muscular action of the lower extremity. Atwater distinguished between the overarm and sidearm throwing patterns in terms of the direction in which the trunk laterally flexed. When lateral flexion occurred away from the throwing arm, and overarm pattern was used; lateral flexion toward the throwing arm indicated a sidearm pattern.

The underarm patter is distinguished by motion predominantly in a sagittal plane with the hand below the waist. Each pattern involves a preparatory movement referred to as a backswing, or windup, followed by the establishment of a base of support prior to the initiation of the force phase and ending in the follow-through. The base of support in the direction of the force application; forward and backward is a distinguishing feature of skill level. It has been well documented that more highly skilled individuals have longer strides.

Once the base has been established, the more proximal segments begin the force application phase while the more distal segments complete the backswing. The purpose of the backswing is the place the segments in a favorable position for the force phase. For the overarm pattern, this kind of throw is characterized by rotation at the shoulder joint. In the backswing or preparatory, phase the abducted arm rotates laterally, and in the forward, or force, phase the arm rotates medially. Some elbow extensions, wrist flexion and spinal rotation occur in the force phase. These movements are accompanied by ration of the thigh.

An immature pattern may be identified as using fewer segments, working more simultaneously rather than sequentially, and involving a more limited range of motion. Overhand patter applied in baseball pitch using forward force phase is characterized by medial rotation of the arm, elbow extension, spinal rotation, and medial rotation of the pelvis at the contra lateral hip joint. Underarm patters consist of a forward movement of the extended arm in the sagittal plane, usually starting from a position of hyperextension and ending in a forward reach. The basic joint action of the arm if flexion.

The actions of the wrist, spine and pelvis are the same as those observed in the overarm pattern. In a sidearm pattern the basic movement is medial rotation of the pelvis on the opposite hip with the arm usually in an abducted position. The arm is moved forward in a horizontal plane because of the pelvic action and spinal rotation. The spine also laterally flexes toward the throwing arm. The range of the upper-extremity movement many also be enlarged by the addition of horizontal abduction at the shoulder. The elbow is maintained in extension or is extended from a slightly flexed position, depending on the nature of the skill in question for example batting throwing a basketball for distance or tennis forehand drive.

Wrist flexion may also be part of the action in some techniques. Anatomical principles are very important when it comes to throwing. To ignore this principle of sequential motion is to risk injury because sequential motion can generate extremely high velocities, as well as impart high braking forces. Muscles contract more forcefully if they are first put on a stretch, provided they are not overstretched.

This principle suggests the function of the windup in pitching and if the preliminary movements in other sport skills. Unnecessary movements and tensions in the performance of a motor skill mean both awkwardness and unnecessary fatigue; hence they should be eliminated. Skillful and efficient performance in a particular technique can be developed only by practice of that technique. Only in this way can the necessary adjustments in the neuromuscular mechanism be made to ensure a well-coordinated movement. The most efficient type of movement in throwing skills is ballistic movement. Skills that are primarily ballistic should be practiced ballistically, even in the earliest learning stages.

This means that from the beginning the emphasis should b placed on form rather than on aim. Accuracy of aim will develop with practice. If the emphasis is placed on accuracy in the learning stages, the beginner tends to perform the skill as a moving fixation or as a slow, tense movement. Once this pattern of movement is established, it is extremely difficult to change it later to a ballistic movement. When there is a choice of anatomical leverage, the lever appropriate for the task should be used. A lever with a long resistance arm for movements requiring range or speed, and a lever with a long effort arm for movements requiring strength.

Although many of the mechanical principles for throwing are similar to those for pushing and pulling, the applications of these principles are different. Whereas force application in push-pull patterns is maximized through using large numbers of segments simultaneously, force in throwing patterns is maximized through sequential transfer of momentum from large segments to less massive segments. The efficiency of imparting force to a ball is judged in terms of the speed, distance and direction of the ball after its release. The purpose of the throw determines which of these is given the greater emphasis. Both the speed and distance of the thrown ball are directly related to the magnitude of the force used in throwing it and to the speed of the hand at the moment of release. The speed the hand is able to achieve depends on the distance through which it moves in the preparatory part of the act and the summed angular velocities of the contributing body segments.

Hence, the longer the preparatory backswing and the greater the distance that can be added by means of rotating the body, shifting the weight, and perhaps even taking a step, the greater the opportunity for accelerating. Approximately 50% of the ball speed is obtained from the forward step and body rotation. The remaining speed is contributed by the joint actions in the shoulder, elbow, wrist and fingers. This is why the technique of a baseball pitcher is designed to allow maximum time and distance over which to accelerate the ball before its release. In addition, if the ground reaction force is to be maximal, the surface against which the thrower pushes must be firm and there must be no sliding between the ground surface and the foot. The more the direction of the body thrust is backward, the more important the friction becomes and the more the value of the created shoes is appreciated.

If distance is a major objective of the throw, the angle of projection and the effects of gravitational force and air resistance must also be taken into consideration. The accuracy with which a ball is thrown depends on accurate judgment of the distance and direction of the throw's target. The ball will leave the hand in the direction it is moving at the instant of release and continue in that direction expect for modifications because of gravity and air resistance. Therefore the effect of gravity, wind, and spin must be considered, as well as the release direction.

If the hand is traveling in an arc at release, the ball will follow a path tangent to the arc, and the timing of the release is highly critical. Flattering the arc of the ball's path prior to release increases the margin of error by allowing more time over which the ball can be released in the desired direction. This may be done by taking a step and shifting the weight forward while flexing at the forward knee. The rotation of the pelvis and spine also helps. When the object being thrown is other than a small ball, such as a javelin, discus, bowling ball, or horseshoe, the general principles are the same but must be modified according to the nature of the object and the regulations of the sport. An overarm pattern is analyzed as applied in a forceful throw such as in pitching.

This analysis includes joint actions, muscle activity, and mechanics for the upper extremity only. The purpose of the backswing or preparatory, motion is to place the segments in a favorable position for the force phase. There are many ways to execute the backswing. Although some favor one method over another, any windup is appropriate that places the segments in the most advantageous position to maximize the number of segments and the time over which force can be applied.

Such a windup allowing the joints to be placed in an optimal position to involve the greatest number of segments, includes pelvic and trunk rotation in the opposite direction from the intended throw, horizontal abduction and lateral rotation at the shoulder joint with elbow flexion and wrist hyperextension. This sequence of arm action continues as a forward step is take with the opposite foot. This hand-foot opposition permits the greatest range of motion in the trunk and pelvis. It also allows for a large base of support over which the force phase can be applied while preserving balance. No pause occurs between the windup and the force phases. The windup ends with a forward stride using the opposite leg.

Establishment of a base of support is followed immediately by pelvic and then trunk rotation, accompanied by lateral flexion to the left (right handed pitcher) The trunk motion causes increased horizontal abduction with continuing lateral rotation at the shoulder joint. Elbow joint extension is followed by the initiation of rapid medial rotation at the shoulder joint, forearm pronation at the radial-ulnar joint, and then flexion and often ulnar flexion at the wrist joint. The force phase ends with the release of the ball. The angle at the elbow joint at release is approximately 105 degrees. The follow-through includes the actions from ball release until the momentum developed in the arm can be safely dissipated as the arm continues across the body in a downward direction. In addition, a forward step is also often used.

The legs play an important role in any successful throw. They provide the stable base over which the trunk and other segments act. In addition the thrust they provide contributes significantly to the force of the movement. The transfer of momentum from proximal to distal, however focuses the attention on the musculature of the upper extremity.

Because this phase emphasis the application of the force accelerating the limb muscle contractions are mainly concentric preceded by a short eccentric phase because of the lagging of the distal behind the proximal segments. The lateral rotation preceding the medial rotation of the right shoulder joint is controlled by the eccentric contraction of the medial rotators of the humerus followed by the concentric contraction of the same muscles, including the subscapularis, pectoralis major, and latissimus dorsi muscles. During the acceleration phase the height of the humerus was controlled by a static contraction of the middle deltoid. The deltoid and muscles contract concentrically during the backswing to position the upper arm, and eccentrically during the follow-through to help decelerate the arm. The muscle was also very active to assist in decelerating the arm during the follow-through.

The biceps brach ii muscle activity reaches its peak as the elbow joint is flexed late into the backswing and at the beginning of the force phase. Marked activity again appears during the follow-through to protect the elbow joint in deceleration the forearm. The latissimus dorsi muscle remains active eccentrically contraction during the follow-through to assist in controlling the arm motion across the body. The stretch reflex is an important facilitation mechanism in helping accelerate the lagging distal segment at the appropriate time. The more rapid the stretch the greater will be the facilitating effect of the resulting concentric contraction of the same muscle. To gain the greatest facilitation from the stretch reflex, there should be no pause between the windup and force phases.

The extensor thrust reflex may act on both the upper and lover extremities. Increasing pressure on the palmar side of the hand as the arm is being accelerated forward may facilitate the arm extensor muscles. Similarly, as the weight is transferred to the forward foot, the corpuscles are stimulated by the increased pressure, resulting in a facilitation of the lower-limb extensor muscles. When accuracy is a factor, knee flexion must be maintained to flatten the arc through which the hand is carried. This flattening permits the tangential flight path of the ball to have a broader margin for error in the timing of the release while arriving at the same target point following release. When pitching is looked at in the big picture almost all of your upper muscles are being put to work.

Pitching may look easy but the biomechanical aspect of it are not. Pitching a ball numerous times will put a lot of wear and tear on anyone's body. Taking care of your arm after pitching is extremely important because when your muscles are over used they can become sore and painful. Stretching these upper body parts will help prevent serious injury and pain. Your arm is a valuable part of your body and making sure it is healthy is important because in the future major problems could occur.