Muscles and Movement Flashcards
Superior
Above/top/towards the head
Inferior
below/bottom/away from the head
Anterior
Towards the front
Posterior
Towards the back
Proximal
Closer to the trunk/origin
Distal
Away from the trunk/origin
Medial
Towards the mid-line
Lateral
Away from the mid-line
Deep
Inside the body and away from the surface
Superficial
Towards the surface
What are the three planes of movement?
Sagittal, transverse and frontal
Axis for sagittal plane
Frontal horizontal axis
Axis for transverse plane
Vertial axis
Axis for frontal plane
Sagittal horizontal axis
Concentric
Muscle is in tension and shortening
Eccentric
Muscle is in tension and lengthening
Isometric
Muscle is in tension and length stays the same
Passive movement
Muscle is not under tension
Agonist
The muscle(s) responsible for performing the movement - prime movers.
Antagonist
The muscle(s) that could oppose the agonists if activated
Stabilisers
Muscles that contract to stabilise nearby joints
Synergists
Muscles that assist in the action of the agonists (guiding muscles)
Approximate number of muscles in the body
600
4 muscle functions
Movement - contracts to move bones
Maintain posture
Store and move substances
Thermoregulation
How does skeletal muscle produce movement?
Force is produced by the muscle
Force is transmitted to the skeleton via the tendon
> Movement occurs/joint is stabilised/posture is maintained
Pennation angle
Angle between orientation of muscle fibres and the tendon (or line of pull). Usually up to 45 degrees
Difference in tension between parallel and pennate muscles and why
Pennate muscles have a higher tension than parallel of the same size as pennate muscle fibres pull at an angle to the line of pull.
Example(s) of pennate muscles
Rectus femoris and biceps femoris
Origin
The tendon attachment(s) nearest the centre of the body.
Insertion
The tendon attachment(s) furthest from the centre of the body.
Torque
Torque = force x perpendicular distance from pivot
What does it mean if there is a longer lever arm at a pivot joint?
Increase in torque
Decrease range of motion
Decrease joint angular velocity
