Upper Body Analysis Paper

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In the movement phase the quarterback starts to throw the football and it start by abduction and the upward rotation of the shoulder girdle, this is possible by the concentrically contracting of the pectoralis minor, serratus anterior, and the middle and lower portion of the trapezius muscle. The right glenohumeral joint is then internally rotated from the fully externally rotated position and concentrically contracted by the anterior deltoid, upper pectoralis major, latissimus dorsi, and subscapularis. The left glenohumeral joint is horizontally abducted concentrically by the posterior deltoid, latissimus dorsi, infraspinatus, and teres minor. The right humeroulnar joint is concentrically extended by the triceps brachia and anconeus. The left humeroulnar joint is isometrically flexed by the biceps brachia, brachioradialis, brachialis, and pronator teres. The right radioulnar joint is in a neutral position and is isometrically held in this position by the brachioradialis, the left radioulnar joint is supinated concentrically by the biceps brachia and supinator. The radiocarpal joints are concentrically flexed by the wrist flexors which include: flexor carpi radialis, palmaris longus, flexor carpi ulnaris, flexor digitorum superficialis,

Wells 4

flexor digitorum profundus, and flexor pollicis longus. The finger and thumb joints are flexed concentrically by the finger and thumb flexors.

The last movement or the follow through movement is when the quarterback has just released the ball. Most of these movements are eccentrically contracted because the force is no longer being generated so the muscles act as a cushion to slow down the limbs. The right shoulder girdle is abducted and upwardly rotated eccentrically by the pectoralis minor, serratus anterior and the middle and lower trapezius. The left shoulder girdle is downwardly rotated and depressed eccentrically by the lower trapezius, rhomboids, and pectoralis minor. The right glenohumeral joint is extended backwards eccentrically by the posterior deltoid, latissimus dorsi, teres minor and major, infranspinatus, and subscapularis. The right humeroulnar joint is eccentrically extended by the triceps bracia and anconeus. The left humeroulnar joint is being isometrically flexed by the biceps brachia, brachioradialis, brachialis, and pronator teres. The right radioulnar joint is eccentrically pronated by the pronator teres and pronator quadratus. The left radioulnar joint is being supinated and isometrically contracted by the biceps brachia and supinator. Both of the radiocarpal joints are eccentrically flexed by the wrsit flexors to soften the force applied on the wrists from snapping the football. The finger and thumb joints are eccentrically extended by the extensor digitorum, extensor indicis, extensor digiti minimi, abductor pollicis longus, extensor pollicis longus.

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