How does our body work?
Its all about simple machines called levers. Every time you move, muscles and bones work together as hundreds of tiny lever systems
What are the 4 key parts of a lever system?
- Fulcrum - the pivot point of rotation (your joints)
- Load - the resistance or force to be moved
- Effort - the force applied by your muscles
- Lever arm - the rigid bar that moves (your bones)
What are some examples of a fulcrum?
The elbow joint(during a bicep curl)
The neck (when lifting your head)
The ankle(during a calf raise)
What is a fulcrum?
The pivot point of rotation (your joints)
What is a load?
The resistance or force to be moved
What is the effort?
The force applied to the load by your muscles
What is the lever arm?
The rigid structure, usually a bone like the forearm or the whole leg, that pivots around the fulcrum
What lever system would a see saw fall into?
A first class system - the fulcrum in the middle
What is a first class lever?
In a first class lever, the fulcrum sits in the middle, between the load and the effort
What is an example of a first class lever system in our body in sports?
Completing a header
Load - the weight of your head
Fulcrum - your neck joint
Effort - your neck muscles
What is a second class lever?
The load sits in the middle, between the fulcrum and the effort
What is an example of a second class lever system?
Calf raise:
Fulcrum - the ball of your foot
Load - your bodyweight
Effort - your calf muscle (gastrocnemius)
What is a good analogy for a second class lever system?
Using a wheelbarrow
What is a third class lever system?
The effort sits in the middle, between the fulcrum and the load
What is an example of a third class lever system?
Bicep curl:
Fulcrum - the elbow joint
Effort - your bicep muscle
Load - the weight in your hand
What is a good analogy of a third class lever system?
Using a spade:
Fulcrum - hand at the top of the handle
Effort - foot pushing on the spade
Load - the weight of the soil
What is meant by mechanical advantage?
This happens when the output of the lever is greater than the input
First and second class levers both work at a mechanical advantage
What is meant by mechanical disadvantage?
This happens when the effort and the load are both the same side of the fulcrum but the effort sits closer to the fulcrum than the load does.
Third class levers work at a mechanical disadvantage
What is the best way to remember which lever is which?
FLE:
F - fulcrum - middle of the first class lever
L - load - middle lf the second class lever
E - effort - middle of the third class lever
Why do first and second class levers operate at a mechanical advantage?
First and second-class levers operate at a mechanical advantage when the effort am is longer than the load arm, allowing a small input force to move a large load.
Why do third class levers operate at a mechanical disadvantage?
Third-class levers operate at a mechanical disadvantage because the effort arm distance from fulcrum to effort is shorter than the load arm distance from fulcrum to load. However they generate speed and has a greater range of motion
-
Soc 111
-
Soc 29
-
Soc 38
-
Soc 425
-
Soc 5&619
-
Soc 720
-
Soc 811
-
Soc 916
-
Soc 10 Injuries17
-
Soc 11 PEDs23
-
Soc 12 - Skeletal System18
-
Soc 13 - Joints, Movements , Ligaments And Tendons9
-
Soc 14 - Muscles10
-
Soc 15 Cardiovascular8
-
Soc 16 : Structure Of The Blood Vessels13
-
Soc 17 - The Structure Of The Respiratory System14
-
Soc 18 Anaerobic , Aerobic Exercise And Energy Sources15
-
Soc 19 - Short And Long Term Affects Of Exercise16
-
Soc 20 - Levers21
-
Soc 21 - Planes And Axes Of Movement17
-
PAPER 2 soc 22 - Physical Emotional And Social Health6
-
Soc 23 - Lifestyle Choices21
-
Soc - 24 Sedentary Lifestyle13
-
Soc 25 - Energy Use, Diet And Hydration20
-
Soc 26 - Skills Practice, Guidance And Feedback33
-
Soc 27 - Engagement Patterns In Sport9
-
Soc 28 - Commercialistation Of Sport9
