basic muscle movement Flashcards
describe how a body is aligned when it is in “stable equilibrium”
a body is in stable equilibrium when the line from its centre of gravity lies within its base of support.
what is the “base of support”?
the area by which a body is supported
what does a body being in “unstable equilibrium” mean?
a body is in unstable equilibrium if, after being displaced it becomes further displaced
where is the centre of gravity?
the point at which all forces acting on the body are equally balanced
the ability to generate tension is the ___ of the muscle?
the strength of a muscle
what will the amount of movement generated will depend on?
- force of muscle, contraction/tension provided
- resistance
the relationship between the internal force (tension) generated and the external load (resistance) is…
Muscle contraction
Describe Fixation and how it is obtained and what it is used to maintain
- state of immobility
- usually obtained by contraction of muscles around a joint
- used to maintain posture
- localising movement
Describe what stabilisation is
relative immobility
equal forces
IsoMETRIC contraction
- muscle is stimulated
- length remains unchanged due to an external force
- fixated joint
- force produced does not overcome resistance
- no movement, but stability
- e.g. postural muscle contraction, sustained grip
IsoTONIC contraction
- stimulated muscle contracts and changes in length
- e.g. two ends come closer together and a joint moves
IsoTONIC: Concentric
- muscle shortens
- bones are moved and movement is visibly seen
- muscle belly shortens in length
IsoTONIC: Eccentric
- Muscle Lengthens
- Muscle being used to control movement of a body part against force e.g. gravity
- “break action”
Agonist (Muscle group / Role)
- contracts to provide the force to facilitate movement
- muscle with the major role called the “prime mover”
Antagonist (Muscle group / Role)
Works in opposition to the Agonist
