W7 - Constraints-LED Motor Learning

Question 1

What are the 3 stages of Motor Learning according to Bernstein’s Stages of Motor Learning?

Answer 1

Stage 1 : Freezing of the degrees of freedom
Stage 2 : Releasing and Reorganising
Stage 3 : Exploiting mechanical properties

Question 2

Name some characteristics of complex systems

Answer 2

• Many independent and variable degrees of freedom (how muscle is innovated is determined within the structures)
  
  • E.g. Neural(muscles), mechanical(physical ability), psychological(what we want to do) - there are limits in each of these components, so determines the outcome
  • The ability of subsystem components to limit or influence the behaviour of other subsystems

Question 3

Name some examples of organismic constraints:

Answer 3

Human characteristics

• Height
• Weight
• Strength
• Flexibility
• Motivation
• Emotion

Question 4

Provide examples of environmental constraints:

Answer 4

Physical & Social

• Gravity
• Light
• Temperature
• Weather
• Culture
• Expectations

Question 5

What are some examples of task constraints?

Answer 5

Specific to Performance

• Task Goals
• Rules
• Equipment
• Playing Surface
• Line Markings
• Specific Obstacles

Question 6

Describe the Perceptual-motor Landscape by Davids et al.

What does Attractor mean?

Answer 6

A repertoire of movement attractors which are co-ordinated with the environment in order to perform skills effectively. As constraints change, so does the landscape.
- Done to search for a solution that satisfies the constraints
* Adapting as constraints change
* Stabilise successful coordination pattern - finding what works and practising it (make it an attractor)

Attractors - preferred state (e.g.: having both limbs carrying out the same movement) - usually when a certain freq is reached
- Gymnast with lots of different motor programs performing on beam/ gymnast with lots of different movement attractors on beam

Question 7

What is the reduced strength constraint an example of?

What can be determined from this?

Answer 7

Perceptual-Motor Landscape

Full strength = simulation of elite male gymnast strength
Reduced strength = simulation of 75% strength of elite male gymnast
- The gymnast can be 100% successful in full strength is anywhere in the white circle
- By constraining the gymnast we are forcing the gymnast to move in a very particular way (success rate is directly under the green star)
- Constraints force us into finding that correct movement pattern

Question 8

What are the 3 stages in Newall’s Model of Motor Learning?

Answer 8

1) Assemble a coordination pattern
- establish relationships: swing - step - release
Interactions: surfaces (the lane), obstacles (gutter), equipment, strategic goals
- Without these constraints the coordination pattern may be completely different
i.e.: explore the perceptual-motor landscape

2) Gaining control of a coordinative structure
- tighter fit: coordination & performance environment, e.g.: vary the values of important parameters

3) Skilled optimisation of control, e.g.: In slightly different conditions we know how to optimise the parameters of the system to get the desired outcome
- Large solution space

Question 9

What are some ways to manipulate constraints?

What is the aim when manipulating constraints?

Answer 9

• Rules
  
  • Equipment
  • Surfaces
  • Obstacles

manipulating factors encourages the correct coordination pattern (pushing someone towards/able to produce the correct coordination pattern)
e.g.: Giving a child a smaller and lighter ball for them to produce the movement pattern that is correct to knock down the pins