Motor Behavior During Childhood

1
Motor Behavior During Childhood

• Laws of motion and stability
• Movement governed by principles of motion and
  stability
• Environment influences movement patterns
• Growth changes size, proportions
• Optimize skill performance based on these laws
• Force
• Newtons first law of motion external force must
  act on a resting object to cause it to move
• Maximize performance apply force over greatest
  distance
• Optimal Force characterized by
• Preparation
• Application of force through full range of motion

2
Action/Reaction

• Newtons 3rd law of motion For every action
  there is an equal and opposite reaction
• Want to exert as much force as they can
• Also applies to parts of the body
• Extension of a limb
• Ballistic task limb traces part of circle
• Releasing or striking an object flies away from
  curved path in a straight line

3
Open Kinetic Chain

• Maximal ballistic effort involves several parts
  in sequence
• Sequence must be tied so force of each succeeding
  movement is applied just after the previous
  movement to accelerate the object
• Force Absorption
• Can minimize force by dissipating it over a
  distance or over area
• Increase distance or area to better absorb force

4

• Base of support
• Larger the base the more stability
• Kids start out with wider stance until gain more
  balance
• Skilled just wide enough to maintain stability
• Qualitative changes in motor skills
• Skill developmentgradual process of refining
  skills
• Many have described development through sets of
  successive steps
• Developmental sequences
• Can apply developmental steps in two ways
• Describe characteristics for Step 1.
• Component model
• Sometimes reach transitions

5
Locomotor Skills

1. Walking
2. Running
3. Jumping
4. Hopping
5. Galloping
6. Sliding
7. Skipping

6
Walking

• Acquire near adult walking by age 5
• Walk alone between 9 and 17 months of age
• Early walking
• Short steps -flat footed
• Toes pointed out -knee bent
• Wide stance -very little trunk rotation
• Hands and arms carried high in bent position
• As develop, drop to waist
• Later extend arms at sides

7
Proficient Walking

• Stride length increase
• Heel to forefoot pattern
• Decrease in out-toeing, narrow base of support
• Double knee lock pattern
• Pelvis rotates
• Increase in balance
• Oppositional arm swing

8
Developmental Changes

• Age 2 ingredients for fast walking
• Pelvic extension 14 months
• Knee flexion 16 months
• Narrow support 17 months
• Oppositional arm swing 18 months
• Stride length increase through adolescence
• Increase velocity 1-3.5 years
• Rhythm and coordination improve up to 5 yrs

9
Observing Walking

• Need for practice
• Focus on specific body components
• One segment at a time
• Arm position and opposition
• Videotaping from front and side

10
Running

• More advanced but similar to walking
• Period of flight
• Flight phase 6-7 months after learn how to walk
• Earliest running attempts are fast walking
• Some suffer regression with fear of the new skill

11

• Early Running
• Rear leg doesnt extend fully
• Arms extend when swing back
• Sometimes swing horizontally
• Proficient Running
• Increase stride length
• Fully extend rear leg at push off
• Knee bent in forward swing
• Eliminate lateral leg movement
• Heel-toe landing
• Eliminate out toeing and keep narrow base of
  support
• Support leg flexes with weight
• Increased trunk rotation
• Arms swing forward and back, elbows at right
  angles

12
Developmental Changes

• Above changes with increased size and strength
  lead to increase speed and time of flight
• Most teenagers continue to refine running form
• Some adults don't run correctly
• May reflect imbalance
• Walking and running are symmetrical and involve
  50 phasing
• Can observe running using same methods as walking