How Skeletal Muscles Produce movements

Question 1

What is a (RMA) Reverse muscle action?

Answer 1

This occurs during certain movements of the body when the action is reversed and the portions of the (O) and (I) of a specific muscle switch.

Question 2

What is a lever in relation to Muscles?

Answer 2

This is a Rigid Structure that can move around a fixed point called a “Fulcrum”.

Question 3

What is a Fulcrum?

Answer 3

This is what the lever moves around when creating force and a Joint in the body acts as this.

Question 4

What is the force that creates movement in the body?

Answer 4

Effort.

Question 5

What is the Opposing feature of the Effort?

Answer 5

Effort is resisted by “Load”.

Question 6

Where does the “effort” come from in the body?

Answer 6

The Effort is exerted by muscle contraction.

Question 7

What is a First Class Lever?

Answer 7

The Fulcrum is between the Effort and the Load. 
A first class lever can produce a Mechanical Advantage r disadvantage. Depending on if the Effort or load is closer to the Fulcrum.

Question 8

What is a Second Class lever?

Answer 8

The Load is between the Fulcrum and the Effort.

They always produce a Mechanical Advantage because the load is always closer to the fulcrum than the effort.

Question 9

What is a Third Class lever?

Answer 9

The Effort is between the Fulcrum and the Load. 
Third class levers always produce a Mechanical Disadvantage because (The effort is always closer to the Fulcrum than the Load).

Question 10

What Determines if a lever will have a Mechanical advantage or disadvantage?

Answer 10

This is determined whether The relative distance between the Fulcrum and Load applied and the point at which the effort is applied.

Question 11

What would provide a Mechanical Advantage?

Answer 11

For ex: If the Load is closer to the Fulcrum and the Effort is further from the fulcrum.
Then relatively less Effort is needed to move the load. over a small distance.

Question 12

What would provide a Mechanical Disadvantage?

Answer 12

For ex: If the load is further from the Fulcrum and the effort is applied closer to the fulcrum.
Than relatively more effort is needed to move the Load.

Question 13

How are levers categorized?

Answer 13

They are sorted based on:

Positions of the Fulcrum, The effort and the Load.

Question 14

What is an example of a First Class lever?

Answer 14

The head resting on the vertebral column, when the head is raised the contraction of the posterior neck muscles provide the effort, the Atlanto occipital joint is the fulcrum, And the weight of the anterior portion of the skull is the Load.

Question 15

What is an uncommon Type of lever in the human Body?

Answer 15

Second class lever.

Question 16

What type of lever favours speed and ROM over force?

Answer 16

Third Class levers.

Question 17

What is an Example of a Second class lever?

Answer 17

An example of this is standing on your toes.
The ball of your foot is the Fulcrum, The load is your bodyweight, The effort is the Contraction form the Calf muscles because they raise the heel off the ground.

Question 18

What is an example of a Third class lever?

Answer 18

The Elbow joint is the Fulcrum, The effort comes form the muscles of the Anterior Arm such as the Bicep brachii, The weight of the forearm and the hand is the load + Added weight.