Analyzing the system [1]

Question 1

What is qualitative motion analysis and what are the 2 approaches?

Answer 1

QMA: describes how the body looks as it performs skills, such as position in space, position of body parts relative to each other, and position of segments of body parts in relation to each other

2 approaches:
1. composite approach
2. component approach

Question 2

What is the composite approach?

Answer 2

**total body approach **
- stages of skill progression are based on the product of all body parts in combination.
- each stage/phase identifies important **body parts **used to perform the skill

not using specific muscles

Question 3

What is the component approach?

Answer 3

error-analysis strategy
- each primary body component is observed
- each component has its own evaluative series of stages that can be advanced through independently of each other

Question 4

Describe an overhand throw in both approaches

Answer 4

composite
- chop throw, then sling throw, high cocking phase, trunk rotation & stepping motion added, finally complete throwing motion

component:
- Trunk
1. no trunk motion
2. some
3. optimal trunk rotation

• Upper arm
  1. no backswing
  2. some backswing
  3. optimal backswing

Question 5

What is Quantitative motion analysis?

Answer 5

stems from the understanding of the need for WHY the system moves the way it does
- used by PT’s and when training elite athletes

Question 6

What are the basic concepts of quantitative motion analysis?

Answer 6

Scalar Quantity: a quantity that possesses only a magnitude but NO direction **(mass & inertia)

• scalars also include length, speed, and temp
• mass does NOT = volume

Vector Quantity: can only be fully specificed with a magnitude of appropriate units AND precise direction ex) weight: a measure of the force with which gravity pulls on an objects mass
- they are represented by arrows
- ex of vectors: weight and mass are proportional but not the same bc of gravity

Question 7

What are the 5 ways vectors represent forces?

Answer 7

1. Direction
2. Oreintation
3. Magnitude
4. Point of application
5. Line of action

Question 8

Describe the cartesian coordinate system?

Answer 8

an x/y axis graph
- we can define the position of an object in space by establishing 1 or more frame of reference within this system

Question 9

Describe a polar coordinate system?

Answer 9

Still has an origin and multiple reference axes
- positive x-axis is used as the reference axis
- location of the given point is defined by its disatnce (r) from the origin by Ø between the chosen reference axis and line formed by connecting the point to the origin
- it is measured counterclockwise from the positive x-axis

Question 10

Practice finding component vectors and resultant vectors

Answer 10

draw on paper for these