Levers

Question 1

What are the three components of levers?

Answer 1

Fulcrum - the joint
Resistance (load) - the object you are lifting or the body itself
Effort - the insertion point of the muscle which is contracting

Question 2

What are three classifications of levers?

Answer 2

1st class
2nd class
3rd class

Question 3

What is the chant to classify levers?

Answer 3

123 FRE

Question 4

What are 1st class levers?

Answer 4

The fulcrum is in the middle
Only found during:
- Extension in the elbow
- Flexion and extension in the neck (nodding)

Question 5

What are 2nd class levers?

Answer 5

The resistance is in the middle
Only found during:
- plantar flexion at the ankle

Question 6

What are 3rd class levers?

Answer 6

The effort is in the middle
Found in all joints in the body:
- Flexion at the elbow
- Extension in the knee

Question 7

What are 2 advantages of 1st class levers

Answer 7

• Can produce quick movements
• Have a large range of movement

Question 8

What is a disadvantage of 1st class levers

Answer 8

• Cannot lift heavy loads

Question 9

What is an advantage of 2nd class levers

Answer 9

• Able to lift heavy loads

Question 10

What are 2 disadvantages of 2nd class levers

Answer 10

• Not able to produce quick movements
• Small range of movement

Question 11

What are 2 advantages of 3rd class levers

Answer 11

• Can produce quick movements
• Large range of movement

Question 12

What is a disadvantage of 3rd class levers

Answer 12

• Not able to lift heavy loads