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41 Cards in this Set

  • Front
  • Back
Running OP
pendular action of the legs
Running CP To get to attractor level 1/initiate running
strength of runner
Running CP To get to attractor level 2
velocity of running
3 dissimilarities of running/walking
1.Running never has double support phase
2.Running must have “in flight” phase: neither foot in contact w/ ground
3.Gravity & air resistance are the only forces exerted on the person when projectile (no ground rxn forces)
Running has specific phases phase: when R leg in support, L leg in recovery; support: foot on ground & COG behind the foot or over foot
2.take off phase: when COG is in front of foot flight phase: when foot leaves the ground phase: foot back on ground; recovery: when opposite leg is coming forward
inc velocity of running by:
increase stride length maintaining stride frequency
How far COG travels relates to 3 things
height of release
Attractor Level 1 Runners
•ankle, knee, hip not extended @ take off
•COG well ahead of foot @ take off (20cm)
•Arms in wing position in flight phase
•COG well behind support foot & see backward rotation @ landing
•Flat footed @ landing for stability
•Not much cushion phase
Attractor Level 2 Runners
•Extension seen in 1/couple of joints, but not all three @ take off
•COG closer to take off foot @ take off (10-12cm)
•Arms @ side & move back and forth in front of body
•Heel first @ landing, then step to flat foot
•COG closer to support foot @ landing, but still slightly behind
Attractor Level 3 Runners
•No jerking of upper body: head barely moves up and down
•Head over/slightly ahead of take off foot @ take off
•Complete extension of hip/knee/ankle @ take off to create max force
•@ recovery, recovering leg flexes up a whole lot more (almost in buttocks)
ob/c: reaction from force of ground
oreduces moment of inertia (makes easier to rotate hip) faster stride frequency
•land outside body @ foot strike, then rock to center & heel barely touches the ground
•arms move w/ legs & in the same plane of motion; arms now used for extra forces exerted @ take off, which will increase stride lengthincrease stride velocity
Jumping CP
distance jumped
Jumping OP
impulse produced @ take off
Attractor Level 1 Jumper
•3 ½ years old
•Take step w/ one foot & then take off
oTake off @ angle <30°
oIn air for very short time: leap
•Legs remain separated in air, land on other foot & then quickly bring legs together
•Arms out wide for balance & even wider in flight
•COG just behind support leg @ landing
•Flexion @ ankle, knee & hip @ take off
•Angle remains constant @ ankle, knee, hip in flight
Attractor Level 2 Jumper
•5 years old
•See increase in LBM around this age: this facilitates an increase in forces that can be produced @ take off  increase in impulse produced  jump further
•Angle of take off round 30° b/c more comfortable w/ balance
•Little movement b/w feet @ take off, but may still see slight movement @ first & feet land together
•In flight phase attempt to bring one leg even w/ the other leg & see knees & hip flex @ the same time in preparation for landing
•COG further behind foot @ landing
•@ take off, arms comes down, swing in upward position helping produce more force
•Arms out a little, but closer to body in flight
•Extension @ ankle &/or knee @ take off (hip flex)
Attractor Level 3 Jumper
•Crouch down low: flex @ knees, hip, ankle @ take off
•Arms move far behind body, swing forward when jump
•@ take off, straight line/full extension through hip, knees, ankles
•Arms over head @ take off
•Take off angle >30°
•@ in flight, knees flex 1st then hips in preparation for landing & bring arms down & back
Throwing OP
open kinetic chain
Prerequisites for TAM to occur
•Distal segment in link must be less massive than proximal neighbor
•Distal segment must lag behind its proximal neighbor during movement
Attractor Level 1 Thrower
•4-5 years old
•Total lack of segmental lag
•No rotation of trunk
•Giveaway for level is the preparation for the throw:
oBring ball up in front of body to the side of the head & extend @ elbow joint
•Everything reaches peak velocity @ same time (trunk-humerus-forearm-hand)
Attractor Level 2 Thrower
•6-7 years old
•Preparation for throw: kids bring arm/ball up to the shoulder/head by bringing it up to the side, naturally adducting the elbow, and a little behind the head
•Ipsilateral step: take step w/ same leg as throwing arm
•Hand always lags behind forearm; forearm tends to lag behind humerus most of the time; humerus rarely lags behind trunk
Attractor Level 3 Thrower
•8-9 years old
•Contralateral step: step w/ opposite leg than throwing arm, naturally:
oRotates body to side & allows for trunk rotation forward/backward
oFacilitates the arm to come back more w/ trunk rotated back
oTrunk & humerus rotate together, so even though have trunk movement, don’t see a lot of humerus lag
Attractor Level 4 Thrower
•11 years old
•Turns to side before throw so that opposite shoulder faces the direction they want to throw
•Contralateral step
•Ball comes straight back well behind the body & head
•Trunk rotates 1st, humerus 2nd, forearm 3rd, hand 4th
Catching CP
Tau/visual flow
Color of Object
Size of Obect
Angle @ which object thrown
•3 kinds of anticipation important for catching
timing, receptor, effector aniticipation
Catching OP
Impulse-Momentum Principle
Attractor Level 1 Catcher
•3-4 years old
•Wait for object to hit their chest & them trap the object w/ humerus
onot good visual flow/effector anticipation
•use large ball at 1st to teach catching
Attractor Level 2 Catcher
•5-6 years old
•predominantly use forearms to trap the ball after it hits the individuals chest
osoccer ball size
Attractor Level 3 Catcher
•7-8 years old
•Trap the ball with their hands after it hits their chest
oSoftball size
Attractor Level 4 Catcher
•10-11 years old
•Catch the ball without trapping it against the chest 1st
•Hold hands out & try to bring hands in to trap the ball @ the right time; then bring arms into the chest w/ the ball in hand
•Start moving toward ball to catch it  better effector anticipation developed
•Cannot catch with one hand yet
•Has to place oneself in front of the ball
Attractor Level 5 Catcher
•11-12 years old
•Effector anticipation strongly developed and in good use
•Can run to the ball wherever thrown to catch it
•Can catch from not directly in front of the ball
•Can use one hand to catch
•If ball below the catcher waist, turn hands down & put pinkies together
•If ball above catchers waist, turns hands up & put thumbs together allows for cushioning of the ball
•Angle @ which the ball is thrown is not an issue: as go up attractor levels, angle can decrease
Attractor Level 1 Kicker
•4-5 years old
•Takes no advantage of the kicking OP: open kinetic chain & transfer of angular momentum
•Start well behind the ball (1/2 foots length)
•Squarely face where intend to kick & don’t take a step before kicking- simply lift leg and extend leg
•No trunk rotation & very little lag w/ trunk & thigh
Attractor Level 2 Kicker
•6 years old
•Figure out if run up to ball & kick, it will go further
•Plant foot right @ back of the ball
•See more segmental lag, which allows us to see more transfer of angular momentum
oLittle trunk rotation, but good shank to thigh lag
•Most kick straight on still
Attractor Level 3 Kicker
•Plant foot with toe a little ahead of the back of the ball
•Complete use of open kinetic chain: all segments lag
•See dip step: when plant to kick, COG comes down & then kick
oAllowing to project ball in air better
oIncrease time can apply torque on the ball
oGives time to rotate trunk more  increasing angular momentum/max advantage of transfer  increase velocity of foot ultimately
Attractor Level 1 Punter
•5-6 years old
•Hold ball w/ hands under the ball in preparing to punt
•1st couple of times, hold ball and drop … find they don’t bring their foot back fast enough, so throw it up in the air before punting
•Expect ball to be tossed higher than the punters head
•See very little movement of the body before the punt: hardly any transfer of angular momentum, simply flex/ext of knee
Attractor Level 2 Punter
•7-8 years old
•Toss not as high as before: about as high as head & not greater
•Still hold hands under the ball
•Larger swing of the leg, greater angle of hip joint, more sweep of the leg
oThis allows for greater transfer of angular momentum, especially from thigh to shank
•May take step before making the punt
Attractor Level 3 Punter
•9-10 years old
•Hold hands @ side of the ball in preparation for kick
•Drop ball to foot, don’t toss it in the air 1st
•Definitely take step before punting w/ opposite foot than punting foot
oThis helps to rotate trunk, allows the thigh to come around faster, but still see no lag
oDo see lag b/w thigh to shank and maybe even a little lag b/w shank and foot
Attractor Level 4 Punter
•12 years old
•Always take 1, and sometimes 2, steps before punting
•Hands placed above and below ball: opposite hand above and same hand as punting foot below
•Guide ball down to foot for punt & remove hands just before punting
oThis allows for a decrease in timing b/c let gravity take over
•More control over angles and velocities
•See complete transfer of angular momentum leading to ultimate increase of velocity in the foot
oTrunk rotates, thigh lags, shank lags, foot lags
•See dip step just before bring punting leg forward
oIncreasing opportunity to rotate trunk
oIncreasing time to exert torque on leg
•Tau and effector anticipation well-developed
Attractor Level 1 Striker
•5-6 years old
•Shoulders square away and face ball where coming from
•Bat sits on shoulder & dominant hand is further down on the bat: cross hand position
oThis is b/c it takes the strongest arm to provide leverage to get the bat off the shoulder & be able to swing
•Bat moves almost entirely in Y axis/sagital plane
•Very little opportunity for transfer of angular momentum down to the bat
Attractor Level 2 Striker
•Bat still sits on shoulder
•Batter takes ipsilateral step
•See some trunk rotation & transfer of momentum to arms & bat at the same time
•Bat down @ 45°- giving motion in sagital & frontal planes
•Cross-hand position still: dominant hand on bottom
Attractor Level 3 Striker
-batter stands @ open 45 angle
-short contralateral step taken
-trunk rotates
-no cross hand grip
-bat a little off shoulder
-R wrist supinated/L wrist pronated
Attractor Level 4 Striker
-wrist roll @ contact
-stand w/ shoulder facing direction where ball coming
-body rotates 1st w/ swing
-max adv OPC
-hands & bat transfer velocity
Striking CP:
Mass of bat