Section 2: movement analysis

What is a lever

This is a rigid bar that moves about a fixed point when force is applied on it

What are the parts of a lever system

• The lever arm

• The fulcrum

• The effort

• The load

What is the lever arm

The bone being moved around a point

What is the fulcrum

The joint where the lever arm pivots

What is the effort

The force applied by the muscles to the lever arm

What is the load

Its pulls against the muscles on the lever arm

What is the first class lever

The load and effort are at opposite ends of the lever and the fulcrum is in the middle e.g Elbow extension football thrown in

What is the second class lever

The fulcrum and effort are at the opposite ends of the lever with the load in the middle e.g plantar and dorsi flexion

What is the third class lever

The load and fulcrum are at opposite ends with the effort in the middle e.g elbow flexion (lifting a weight) and flexion and extension at the knee

What is the distance between fulcrum and effort

Effort arm

What is the distance between fulcrum and load

Weight or resistance arm

What is the mechinal advantage

Effort arm divided by weight arm

Why does the 2nd class lever have a high M.A ( higher than 1)

This is because the weight arm is shorter than the effort arm. So it can carry large load with minimal effort

What happens with a lever with small M.A (less then 1)

It requires much effort from muscles to move a small load but it can move quickly through a large range of movement. The effort arm is shorter than weight arm

What is a plane of movement

This is an imaginary flat surface which runs through the body

What are the examples of planes

• Sagittal: left and right

• Transverse: top and bottom

• Frontal: front and back

What are axis of movement

This is an imaginary line that runs through the body

What are the three axis

• Sagittal: front to back

• Transverse: left to right

• Longitudinal: top to bottom

What are the types of movements using different planes and axes