Levers
First class lever
Third class lever
Second class lever
Functions of levers
increase the load that a given effort can move
increase the speed at which the body moves
example: heading a ball - effort is the neck muscles (traps/delts), load is the ball, fulcrum is the neck - fulcrum is in the middle
the three components
Fulcrum
Effort
Load
the point at which the lever rotates
the location where the resistance is being moved
muscles - the location where the force is applied
the most common lever in the body
the most efficient lever
mechanical disadvantage - the load can be moved quickly - if resistance arm in extended, greater speed at the resistance and the load is released at a greater speed
example: kicking a football - effort is the quads, fulcrum is the hinge joint at the knee, load is the ball
innefficient at applying force
example: standing on tip toes to mark a player a netball - effort is contraction of gastrocnemius muscle, loads is the body weight, fulcrum is the toes - load is in the middle
FLE/123