Unit 3 Muscle

Lab

flexion

movement that reduces the angle between two articulated bone

Extension

movement that increases of the angle between two articulated bones

Hyperextension

extension past anatomical position

adduction

movement toward the midline of the body

abduction

movement away from the midline of the body

protraction

movement in an anterior direction within the horizontal plane

retraction

movement in a posterior direction within the horizontal plane

elevation

movement in a superior or upward direction

depression

movement in an inferior or downward direction

circumduction

motion of the distal end of a bone that describes a circle but the
shaft of the bone does not rotate

rotation

pivoting on an axis

pronation

rotation of the forearm that turns the palm down or posteriorly

subination

rotation of the forearm that turns the palm up or anteriorly

inversion

movement that turns the foot inward

eversion

movement that turns the foot outward

lateral flexion

movement that bends the vertebral column toward the side

plantar flexion

movement of the foot so that the toes are depressed with respect
to the ankle

dorsiflexion

movement of the foot so that the toes are elevated with respect to the
ankle

opposition

movement of the thumb toward the palm or other finger (a grasping
motion

origin

attachment point (usually a bone) which DOES NOT change position when the
muscle contracts.

insertion

attachment point (usually a bone) which DOES change position when the
muscle contracts.

agonist

(prime mover) – a muscle chiefly responsible for producing a particular
movement

ex. biceps brachii flexes elbow

antagonist

-muscle that opposes the movement of agnoist

ex. biceps brachii flexes elbow, tricpes brachii extends elbow

synergist

-muscle that assists an agonist in performing a primary action