Phase #4- The Swing

Phase #4- The Swing

1. General Instruction: This is the phase in where the hands, hips, and shoulders drive the bat through the hitting zone in order to make contact with the ball. Bring your hands from starting postion directly to the baseball with a level bat plane, by pulling your bottom hand to the ball. Focus your eyes and fix your head on the ball. Turn hips at ball for power and to matain balance.

2. Shoulder Girdle: While in the swing phase the left shoulder rapidly Adducts (retracts) while the right should smoothly Abbucts (protracts) to support the bat as it drives thru the hitting zone.

3. Shoulder Joint: At the intial part the swing the left shoulder joint begins to externally rotate (teres minor, infraspinatus, posterior deltoid) and transversely abduct (posterior deltoid, lateral deltoid, infraspinatus, teres minor). The right shoulder joint transversely flexes (pectoralis major, anterior deltoid, coracobrachialis, biceps brachii) and medial rotates (subscapularis, latissimus dorsi, teres major, pectoralis major, anterior fibers of deltoid). During contact both right and left shoulder joints are flexed and concentrically contracted. The left shoulder joint will continue through transverse abduction and the  right shoulder joint will continue transversely flex.

4. Elbow Joint:The left elbow is flexed (biceps brachii, brachialis, brachioradials)and concentrically contracted as well as being pronated (pronator teres) during contact of the ball. Right after contact the left elbow begins to eccentrically contract and extended (Triceps brachii, anconeus). The right elbow is flexed (Biceps brachii, brachialis, brachio radials) and concentrically contracted and is supinated (supinator, biceps brachi) during contact with the ball. 

5. Hip Joint: Hip joint is slightly tilted anteriorly (Rectus Femoris & Psoas). The left hip is concentrically contracted and slightly internally rotated. The right hip is concentrically contracted and fully rotates internally during contact (Gluteus Minimus, Gluteus Medius, Adductor Longus, Adductor Brevis, Semimembranosus, & Semitendiosus). The hip contractions go from concentric, to eccentric, to concentric.

6. Knee Joint: The Left Knee is Extended (vastus medialis, vastus intermedius, vastus lateralis, rectus femoris) and slightly medially rotated (popliteus, semimembranosus,semitedendinosus,satorius,gracilis). The Right Knee is flexed and is rotating internally. The right knee is also concentrically contracted and adducted (adductor longus, and adductor brevis).