Throwing Biomechanics: Difference between revisions
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= '''Muscle activation''' = | = '''Muscle activation''' = | ||
Windup == | |||
== Cocking == | |||
== Acceleration == | |||
== Deceleration == | |||
== Follow-through == | |||
= '''Types of Pitches''' = | = '''Types of Pitches''' = | ||
Revision as of 04:49, 17 May 2016
Original Editor - Vinit Kothekar
Top Contributors - Vinit Kothekar, Vidya Acharya, Kim Jackson, Olajumoke Ogunleye, Naomi O'Reilly, Wanda van Niekerk, 127.0.0.1, Rachael Lowe, WikiSysop and Claire Knott
Introduction[edit | edit source]
Baseball pitching is one of the most intensely studying athletic motionCite error: Invalid <ref> tag; name cannot be a simple integer. Use a descriptive title. Although focus has been more on shoulder, entire body movement is required to perform a baseball pitching. Throwing is also considered one of the fastest human motions performed, and maximum humeral internal rotation velocity reaches about 7000 to 7500o/secondCite error: Invalid <ref> tag; name cannot be a simple integer. Use a descriptive title.
Phases of Pitching[edit | edit source]
Overhead baseball pitching has been divided into four, five or six phases depending on the investigator studying the motionCite error: Invalid <ref> tag; name cannot be a simple integer. Use a descriptive title. But most commonly five phases of overhead baseball pitching has been identified. (1) windup, (2) cocking, (3) acceleration, (4) deceleration and (5) follow through.
Windup[edit | edit source]
- The pitcher is facing the batter with the baseball concealed away from the batter and in the glove, and both the feet in contact of the ground. This is known as the windup stanceCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. - For a right handed pitcher, throwing arm is right arm, gloved hand is left, lead/stride leg is left lower extremity and pivot/stance leg is right.
- The phase of windup begins with the initiation of the stride leg and ends when the ball separates from the glove4 and the stride leg reaches highest pointCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. - The ipsilateral leg and trunk rotation approximately 90o and contralateral hip and knee flexCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. - During windup phase the energy is transferred from stride leg to pivot leg and winding up of the stride leg occurs. It is an important phase which is responsible for imparting the velocity which is driven to the point of ball release. It is reported that about 50% of the velocity of the ball during overhead throw is generated from step and body rotationCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. The body’s overall center of gravity is raised and minimal stress is imparted on shoulder during this phaseCite error: Invalid<ref>tag; name cannot be a simple integer. Use a descriptive title. - The purpose of windup is threefold, (1) to establish a rhythm to achieve correct timing for subsequent movements, (2) to conceal the ball and distract the hitter and (3) to place the body in a position that may contribute to the propulsion of the ballCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title.
Cocking[edit | edit source]
Cocking phase is further divided into (a) early cocking and (b) late cocking.
Early cocking phase
[edit | edit source]
- It begins with end of windup phase or when the stride leg reaches its maximum height and it ends when the stride leg contacts the mound/groundCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive titleCite error: Invalid<ref>tag; name cannot be a simple integer. Use a descriptive title. - During an ideal pitch, at this point the throwing arm is in ‘semi-cocked’ position. With arm approximately in 90o abduction, 30o horizontal abduction, and 50o external rotationCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. - As the ball is removed from the glove, the center of gravity is lowered by flexing the knee of pivot leg and the stride leg gradually extends and move towards the batterCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. - Its main function is to allow a linear and angular motion of the trunk, which lands directly in front of the pivot leg with toes pointing slightly inCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. Knee and hip of the pivot leg extend and initiate pelvic rotation and forward tilting followed by upper torso rotationCite error: Invalid<ref>tag; name cannot be a simple integer. Use a descriptive title.
Late Cocking phase
[edit | edit source]
- This phase begins from the point stride leg contacts the ground to the point of maximum external rotation of throwing arm.
- During this phase, the trunk is perpendicular to the batter and upper extremity position is finalizedCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. The pelvis reaches its maximum rotation and upper torso continues to rotate and tilt forward and laterally. - Shoulder is abducted about 90o, 10o to 20o horizontally adducted and laterally rotates to about 175o. Wrist is in neutral and elbow is elevated about shoulder height and is 90o flexed.
- During this phase, a varus torque of about 64 N-m is generated at the elbow and about 67 N-m internal rotation torque is generated at the shoulderCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. Scapula is elevated and upwardly rotated which provides adequate subacromial space to avoid impingement.
Acceleration[edit | edit source]
- The acceleration phase begins from point of maximum shoulder external rotation to the point of ball release.
- The trunk continues to rotate and tilt, and energy transferred through upper extremity.
- During this phase, the shoulder moves into horizontal adduction and internal rotation. A rapid shoulder internal rotation takes place and shoulder moves from point of 175o of humeral external rotation to 100o of humeral internal rotation in about 42 to 58 millisecondsCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. - Ball release takes place between 40o and 60o of humeral external rotation. The elbow first moves to about 120o of flexion and then rapidly extends to about 25o of flexion at ball releaseCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. At ball release elbow extension velocity peaks at approximately 2500o/sec. The wrist moves into flexion from extended position and ends in neutral, while forearm is in about 90o pronation at release.
Deceleration[edit | edit source]
- It occurs from the point of ball release to maximal humeral internal rotation and elbow extension.
- Shoulder is abducted 100o, humeral rotation reaches 0o and arm is horizontally adducted to 35o.
- Greatest amount of joint loading is generated during this phase. Posterior shear force of about 400 N, inferior shear force of 300 N, 1090 N of compressive forces and about 97 N-m of horizontal abduction torque are generated during this phase after ball release.
Follow-through[edit | edit source]
- Follow-through is the phase where the body continues to move forward until the arm has ceased motion.
- The elbow undergoes a rebound effect and is approximately flexed to 45oCite error: Invalid
<ref>tag; name cannot be a simple integer. Use a descriptive title. - During this phase the rest of the body catches up with the arm and it culminates with the pitcher in fielding position.
Muscle activation[edit | edit source]
Windup ==
