Anatomical Levers Flashcards
What is a lever?
> A long bar that pivots (bone)
What is a fulcrum?
> The point where the load is pivoted
What is a load?
> The weight trying to move (body/object)
What is an effort?
> The force applied to move the load (muscle)
What is a first class lever?
> The fulcrum is in the middle, between to effort and load
Give 3 examples of a first class lever
1) Football header
E: neck muscles
F: neck joint
L: head weight
2) Throw in
E: tricep muscle
F: elbow joint
L: football weight
3) Oar of rowing boat
E: arm pulling oar
F: oar lock on boat
L: water resistance
What is a second class lever?
> The load is in the middle, between the effort and the fulcrum
Give an example of a second class lever
> A diver on their tiptoes at the edge of the board
E: gastrocnemius muscle
L: body weight
F: toe joints (ball of foot)
What is a third class lever?
> The effort is in the middle, between the load and the fulcrum
Give an example of of a third class lever
> A bicep curl
F: elbow joint
E: bicep muscle
L: dumbell weight
What is a mechanical advantage?
> A large load can be lifted by a relatively small amount of effort (effort arm is longer)
1st class
2nd class
What is a mechanical disadvantage?
> Cannot lift a large a load with the same amount of effort (load arm is longer)
Can produce a large range of movement with relatively low effort
1st class
3rd class
