Throw and Push Patterns: Movement and Skill Constraints

1. proximal segments in front of projectile with distal segments behind projectile sequential for  v curvilinear path mostly wheel-axle all segments behind projectile pushing the projectile or load simultaneous for  F rectilinear path mostly lever motions THROW Pattern PUSH Pattern

2. Movement Patterns - Related Skills

3. Constraints: Throw/Push Continuum • Mass of projectile • Volume/Size of projectile • Shape/Profile of projectile • Target Area for projectile • Strength/Power of person • Skill of person

4. Throw or Kick End Segment Free [e.g. hand, foot] sequential movement of body segments Jump or Push or Pull End Segment Restrained[e.g. foot, hand] simultaneous movement of body segments OPEN Kinetic Chain CLOSED Kinetic Chain

5. Throwlike Patterns • 1. Proximal Parts Move First • 2. Distal Parts Lag Behind • 3. Achieve either : maximum distance [ HORZ or VERT ] OR maximum velocity

9. Fig J.1 page 338 1. segment A is accelerated which gives L to entire system: segments A, B, and C 2. A rotates cw while B and C lag behind 3. A is THEN decelerated by muscle T 4. To conserve L, B accelerates cw THEN decelerates, C then accelerates cw

10. Transfer L to arm by reducing/stopping L in shoulders

11.  End Point v due to decreasing r • See FIG. J.1 on page 338 L= mk² x • initial k is from axis “a” to top of segment C • when segment A decelerates, the k changes to the distance from axis “b” to top of segment C • when segment B decelerates, the k changes to the distance from axis “c” to top of segment C

12. v = r  • final velocity of hand or foot or implement @ release/impact determines projectile v • r =  d from the axis of rotation [e.g. joint] and the contact point of release/impact • see FIG J.12 on page 352 with regard to r

13. Kinetic Link Characteristics • system of linked segments with a fixed base and a free open end • more massive segments @ proximal end • least massive segments @ distal end • initial motion caused by T applied to base • T gives entiresystem LL= mk² x  OR L = I

14. Sequential Motions • 1. proximal/massive segments move first givingL to entire system • 2. external T decelerates proximal segments • 3. to conserve L, next segment, which is less massive, accelerates with rotation now occurring about a new axis and a smaller k • 4. Each successive segment/link accelerates achieving   than previous segment due to both m and k getting progressively smaller

15. Airborne Reaction Rotation • See FIG 15.16 on page 514 • VB spiker abducts hip and/or flexes knees to I (I = mk²) in lower extremities • turntable demo

16. Flexion/Extension Protraction/Retraction Abduction/Adduction Medial/Lateral Rotate Pronate/Supinate Inversion/Eversion Lever Motions Wheel-Axle

17. Wheel-Axle Motions • muscle T rotates a bone which becomes an axle • the wheel is the adjacent segment positioned at an angle to the axle • the wheel r (radius) is modified via flexion/extension or adduction/abduction • see FIG J.6 on page 346 and FIG J.12 on page 352

18. THROW / PUSH for Speed and Accuracy FIG J.8 page 349 FIG J.10 page 350

19. Enjoy the Break No Class this Friday