Movement analysis

Question 1

Lever

Answer 1

A lever is a rigid bone that turns about an axis to create movement. The force to move the lever comes from the muscles. Levers contain:
Fulcrum - the point of pivot of a lever.
Effort - the force applied to one part of the lever.
Load/resistance - the weight at the other end of the lever working against the force of effort.

Question 2

Types of levers

Answer 2

First class levers - the fulcrum is in the centre of the lever in between the effort and the resistance.
Second class levers - the load is in the centre of the lever in between the fulcrum and the effort.
Third class levers - the effort is in the centre in between the resistance and the fulcrum.

Question 3

Mechanical advantages

Answer 3

Different types of levers in the human body offer different mechanical advantages, enhancing efficiency and effectiveness in different types of movement.
First and third class levers have an effort arm that is short compared to the resistance arm. This enables: Fast movement and A wide range of movement.
Second class levers have a long effort arm compared to the length of the resistance arm.
This allows joints to overcome a large resistance with relatively little effort.

Mechanical advantage = effort arm length ÷ weight (resistance) arm length

Question 4

Frontal plane

Answer 4

Movement on this plane is from side-to-side.
The plane is a flat surface that divides the body into front (anterior) and back (posterior) halves.
Movements along a frontal plane include abduction and adduction.

Question 5

Transverse plane

Answer 5

Movement on this plane involves changes in direction.
The plane is a flat surface that divides the body into top (superior) and bottom (inferior) halves.
Movements on a transverse plane are rotational, or turning, movements.

Question 6

Sagittal plane

Answer 6

Movement on this plane are forwards or backwards.
The plane can be imagined as a flat surface that divides the body into left and right halves.
Movements on a sagittal plane include flexion or extension.

Question 7

Sagittal axis

Answer 7

The axis is a horizontal line that passes through the body from front to back
Movements in a frontal plane take place around this sagittal axis.
Examples of movements around a sagittal axis include:
Star jumps, or jumping jacks, use abduction when arms move outwards and adduction when the arms pull back towards the body.
Cartwheel: the body rotates around a front-back axis during a cartwheel motion.

Question 8

Longitudinal axis

Answer 8

The axis is a vertical line that passes through the body from top to bottom.
Movements in a transverse plane take place around this longitudinal axis.
Examples of movements around a longitudinal axis include:
Ice skating spin involving a 360° turn.
Discus throwers spin before releasing the disc.

Question 9

Transverse axis

Answer 9

The axis is a horizontal line that passes through the body from side to side.
Movements in a sagittal plane take place around a transverse axis.
Examples of movements around a transverse axis include:
Running.
Forward somersault.