General Definitions

Question 1

Movement

Answer 1

The act of moving

Sum of all torques

Question 2

Science

Answer 2

Latin scientia, means knowledge

Question 3

Biomechanics

Answer 3

application of mechanics to biological systems

Question 4

Kinesiology

Answer 4

study of movement

Question 5

Kinetics

Answer 5

quantification of forces (as scalars or vectors)

• forces that produce or change motion
• Linear – causes of linear motion;
• Angular – causes of angular motion

Question 6

Kinematics

Answer 6

quantification of motion (vectors)

• geometry of motion
• Describe time, displacement, velocity, & acceleration
• Linear -motion in straight line; angular - rotating

Question 7

Torques

Answer 7

Rotational Forces

Question 8

Movement subsystems

Answer 8

• Control centre/motor centre
• Passive subsystem
• Active subsystem

Question 9

Control Centre

Answer 9

• Brain
• CNS
• PNS

Question 10

Passive Subsystem

Answer 10

• Bones
• Joints
• Ligaments
• Facia (between active and passive)

Question 11

Active Subsystem

Answer 11

• Muscles

- Tendons

Question 12

Joints

Answer 12

The skeleton is a system of levers that rotate about fixed points when force is applied.

Degrees: measures angular displacement.

• Ball & Socket
• Plane
• Hinge
• Saddle
• Pivot
• Condyloid (Ellipsoid)

Question 13

Fascia

Answer 13

• It forms a whole-body continuous three-dimensional matrix of structural support. Fascia interpenetrates and surrounds all organs, muscles, bones and nerve fibres, creating a unique environment for body systems functioning
• Acts as scaffolding to support whole body
• Role is gradually being understood

Question 14

External Factors to movement

Answer 14

Environment

Context of movement

Question 15

Internal Factors to movement

Answer 15

Motivation

Emotional

Question 16

Quantitative movement analysis

Answer 16

Cause of movement – ie the forces and moments – are calculated from the outcome movement

That means we need to work out what forces act on each body segment to cause/affect the movement

Question 17

Levers

Answer 17

Consists of a rigid body with two externally applied forces and a point of rotation.

The two forces can be either on the same or opposite sides of the centre of rotation (COR).

3 classes of levers
- First
- Second
- Third
Classification is based on fulcrum position in relation to the effort

Question 18

First class levers

Answer 18

Fulcrum is positioned between the force and the resistance

If the fulcrum of the lever is exactly halfway between effort and resistance the mechanical advantage will be 1

Anatomical Examples

• Triceps Brachii inserting into olecranon
• Head extensors (upper cervical spine) inserting into occiput
• Trunk Side Flexors

Question 19

Second class levers

Answer 19

Resistance is between force and fulcrum

• Has a mechanical advantage > 1
• allows large force generation
• has a force advantage

Anatomical Examples

• Triceps Surae
• Rear molars and the muscles of the jaw

Question 20

Third class levers

Answer 20

Force between the resistance and the fulcrum

Most common arrangement in the body

Allows great movement

• Has a mechanical advantage

Question 21

Mechanical Advantage

Answer 21

The ratio of distances:

= length of force moment arm / length of resistance moment arm

If >1 then mechanical advantage

If

Question 22

Application of levers

Answer 22

If you increase the lever arm it generates more force

But force is needed to rotate the limb around the fulcrum ( hip ) – so shorten the lever first eg flex knee then extend it just before you kick the ball