Efficiency Of Movement

Question 1

Is efficient movement the same for every person?

Answer 1

No, but some aspects of movement are consistent across typical, healthy adults.

Question 2

What are the features of efficient movement?

Answer 2

1. Motor equivalence.
2. Avoid extreme joint angles.
3. Uses spring-like elasticity of muscles.
4. Smooth movement: minimal jerk.
5. Straight hand path.
6. Synergies/coordination. Automaticity.

Question 3

What is motor equivalence?

Answer 3

The capacity to perform a given task in a variety of ways

Question 4

What are the advantages of MOTOR EQUIVALENCE?

Answer 4

1. Obstacle avoidance
2. Limb availability: turn on the light with the elbow while carrying a tray.

Question 5

How does the CNS use the elasticity of muscles to create efficient movements?

Answer 5

The CNS treats muscles like springs:

1. Determine the desired muscle length at the end of the movement
2. Let the peripheral system move until it finds that length (Gamma-drive)

Question 6

What makes a movement EFFICIENT?

Answer 6

1. Least cognitive processing
2. Consumes less oxygen
3. Biomechanically ideal pattern (reduces joint stress)
4. High sucess rate
5. Speed
6. Smooth and ease of mvmt, has a flow

Question 7

How would you assess SMOOTHNESS of movement?

Answer 7

• Movements with fewer and smaller accelerations with few isolated or unconnected elements.
• Minimum rate of change of acceleration, also known as “minimum jerk”

Question 8

Most adults follow a very consistent rule when moving the hand in curves:

Answer 8

2/3 power law: hand velocity slow down as the amount of curvature increases

Question 9

How do we develop efficiency in movement?

Answer 9

1. Regulation of intersegmental force dynamics:
   
   • Active and Passive forces
2. Blending successive movement components:
   
   • internal representation of the entire sequence
3. Blending simultaneous movement components
   
   • Integrated and simultaneous tasks

Question 10

intersegmental dynamics requires precise interplay between:

Answer 10

–Active forces: Concentric and Eccentric muscle contractions

–Passive forces: Motion of limbs associated with gravity, momentum, external forces

Question 11

Blending successive movement components requires…

Answer 11

1. Internal representation of the entire sequence
2. Anticipatory activation of components in sequential movement

Question 12

Coupling simultaneous movements requires the interplay between which 2 components?

Answer 12

1. Integrated tasks: steering the wheel and doing visual search. Reaching and grasp 2. simultaneous tasks: walk and chew gum, carry an open cup while walking.

Question 13

How is Dynamic Action Perspective used on efficiency change with learning?

Answer 13

1. Variability in early stages of learning reflects exploratory strategies, search for optimal solution. May be unconscious.
2. Once and efficient solution to a tasks is found, it becomes an ATTRACTOR.
3. Attractors may develop a deep well: the dominant task solution.

Question 14

What is the Task-Oriented System Approach used for efficiency change with learning?

Answer 14

1. Early in learning, various subsystems may need to be trained.
2. With practice on the various aspects of the tasks, one can develop task solution for each subsystem.
3. Integration and coordination yields an efficient task solution.

Question 15

The IDEAL SOLUTION for efficient movement depends and which three aspects?

Answer 15

-Individual -Task -Environment

Question 16

in regards of efficient movement, what is 2/3 power law

Answer 16

velocity slows down as the amount of curvature increases