Throwlike and Pushlike Movement Patterns (source: Kreighbaum 1996 ed, pp 335-355)

• Usual objectives of throw and push patterns• projection of objects for greatest horiz or vert dist

– ex : javelin, discus, shotput

• projection of objects for accuracy with speed a factor

– ex: volleyball, tennis, racquetball, baseball pitch

• Movement pattern terminology review• Throwing patterns are further defined as underarm, sidearm, or overarm

(See Table on slide 2)

• Skills listed under each pattern differ because of constraints– ex: rules governing implement or ball, rules governing target.

• Open and Closed chain movements• Open kinetic chain - sequential segmental action, end segment is free to

move (e.g., baseball pitch)

• Closed kinetic chain - simultaneous end segment movement, end segment meets with “considerable resistance “ (e.g., shot put)

Common movement patterns (Table J.1, p 336)

Understanding questions on segmental movement concepts and terminology

• List three general movement patterns and one sport skill under each pattern.

• How does one distinguish between a movement pattern and a spot skill?• List one sport skill using an overarm, an underarm, and a sidearm

parttern.• List two open kinetic chain activities.• List two closed kinetic chain activities.• What is the difference between an open skill and an open kinetic chain

activity?• What is the difference between a closed skill and a closed kinetic chain

activity?

Throw-like patterns

• Characteristics of throw-like patterns– can be a strike or a kick

– high end-point velocity is critical

– sequential segmental action, object lags behind elbow and/or shoulder

• Open kinetic link model – see slides 6 & 7

• Linear motion of a point on a rotating segment: V = r• Sequencing segmental rotations - kinetic link principle

– system has a base and a free open end

– segmental masses progressively decrease

– an external torque is applied at the base to initiate the movement

– segmental rotational acceleration is timed sequentially

• A model of an open kinetic link system – See slide 9

• Throwlike movements performed while in the air – See slide 10

Understanding questions on sequential segmental rotations

• Which of the following activities does the open kinetic link principle applies: soccer punt, golf swing, jab in boxing, back handspring takeoff, hammering a nail, hammer throw, football pass, bowling.

• State three principles that relate to the use of body segments in generating velocity on the open end of the open kinetic chain.

• How does the radius of gyration relate to throwing an object or swinging an implement?

• Describe the differences in the radius of gyration and the radius of rotation in relation to throwlike movements. Relate those to linear and angular velocity.

Three-segment kinetic link model

Three-segment model: (Fig j.2, p 339)

Whip-like action of segmental system

Three-segment model when airborne:

Throwing motion (sequential)

Segmental sequence when throwing

Pushlike Movements• Pushlike patterns - Simultaneous segmental actions

– Objective is accuracy, or large motive force

– Distal segments move simultaneously, resulting in rectilinear movement of distal segment

– Four differences in throw and push (p 350). In throws:• distal segment “lags back”, segments move sequentially, object moves

curvilinearly, wheel-axle movements (shoulder and hip rotation) involved

• Movements lie on a throw-push continuum, the location depending on constraints of performer and object:– performer strength and skill

– object mass, size, and shape

Understanding questions on pushlike and throwlike patterns

• What four factors distinguish a pushlike pattern from a throwlike pattern?

• List five constraints of the activity, equipment, or performers that would have the effect of putting a pushlike element into an otherwise ideal throwlike pattern.

• List three skills that are not throws per se but that use the upper extremity in a throwlike pattern.

• List three skills that use the upper or lower extremity in a pushlike pattern.

Pushing Motions

Development of throwing motion

Push with armshoulder rotation Step with leg on same side

Step with opposite leg