Phys Ed Studies
5 Functions of Skeleton
Framework- Provides shape and gives structure
Red Blood Cells- produced in bone marrow
Protects- Bodys internal organs- e.g lungs are protected by ribs
Movement- Muscles contract and pull on the bone to move it
Stores- Essential minerals such as phosphorus and calcium
Skeletal Muscles
Characteristics
Fibres
Excitability- Ability to contract in response to chemical/ electrical signals
Extensibility- Capacity of a muscle to stretch beyond its resting length
Contractibility- Ability of a muscle to contract or shorten
Elasticity- Ability of a muscle to return to its resting length after being stretched passed it
Slow Twitch- Marathon runner
Red
Slow contraction speed- endurance
Aerobic system
Low force of contraction
Fatigue resistant
Fast Twitch (Type 2A)- 400m
Intermediate speed of contraction
Moderate contraction of force
Generates greater force
Fatigue resistance- Not as much as slow
Possess some aerobic but uses long term anaerobic[
Fast Twitch (Type 2B)- 100m
Rapid contraction speed
High force of contraction- explosive movement
Anaerobic short term
Fatigue very quickly- low blood supply
Generates greater force and more powerful contraction
