THROWING Phases of Movement Remember to break down
THROWING
Phases of Movement Remember to break down movements into different phases to analyze movements • Stance • Preparatory • Movement/Acceleration • Follow through • Recovery
Throwing Motion
Stance Phase #1 • Comfortable & balanced position • Joints & body parts are aligned • Body is preparing for motion
Wind up #2 • Initiation of throwing motion (ball leaves glove) • Position body so all segments coordinate • Stride leg is lifted
Cocking #3 • Ball leaves glove • Force is applied to ball to increase distance • Stride leg moves forward then plants • Shoulder reaches max ER • Begin force transfer from LE/core to UE
Acceleration #4 • Hand begins to move forward to release ball • “Wound” anterior structures act like a spring to accelerate ball • Arm same speed as ball at release • IR average 6000+ deg/sec • Most common phase for pain
Deceleration #5 • Begins at ball release • Release arc is important – Too early • Pitch high • Drop elbow to compensate = stress shoulder/ elbow – Too late • Inc arm speed = stress shoulder • Ends after strong rotator cuff contraction to allow dispersion of energy in safe way • Forces are 2 x that of acceleration • Posterior cuff slows arm
Follow through #6 • Finishes dissipation of energy and positions body to the field • Begins after cuff contraction • Ends with trail leg on ground • Balanced position
Pitching Cues Often used to teach children how to pitch • “Small step back” • “Fire in the hole” (positions weight bearing foot next to pitching rubber) • “Knee to nose” • “Thumb to thigh, fingers to the sky” • “Toes to target” • “Pull Mama’s shades down” • “Step over the wall” • “Stand in ready position”
Optimum projection conditions Three factors influence the trajectory of a projectile 1. Projection angle • Vertical trajectory, oblique trajectory(0 -90 ), Horizontal trajectory 2. Projection speed • Determines length or size of trajectory 3. Relative height of projection • Higher objects go further
Types of delivery • • Overhead Longer moment arm so more speed Harder to control Comes through the hip Able to use body to add to speed – Increased lateral bending
Types of delivery 3/4 delivery • Erect trunk / vertical forearm – Increased valgus force elbow • Shorter lever arm • Flatter trajectory • Better control, but less velocity • Most popular
Types of delivery Sidearm • Elbow extends early • Increased valgus stress on elbow and anterior shoulder stress • Pitch very flat • Increased injury risk
Types of delivery • • Softball underhand Lower injury occurrence No extreme external rotation Larger muscles used for deceleration Little impingement risk
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