Threshold stimulus = the weakest stimulus that caninitiate a contraction.
Sobthreshol stimulus = Stimulus weaker than what isneeded – no contraction results
Recruitment = When all the motor units are working andtotal whole muscle is contracting
All or none response = Muslce will always contract allof the way
Tetanus = sustained contraction, repeated stimuli atclose intervals (maintains posture)
Tone/Tonus = a sustained partial contraction “Ready togo”
Isotonic = Muscle pulls on attatched structure,movement results
Isometric = Muscle does not shorten, no met movement,muscle does tense +energy is used
Group Action = the coordinated response of a group ofmuscles that brings body movement.
Action = any change in muscle position
Antagonist = works against agonist to cause relaxation
Synergist = 2 or more muscles which work to hold bonesteady
Origin = point of muscle attachment to the morestationary bone
Insertion = point of attachment to the more moveablebone
Flexion = Motion which decreases the angle between 2bones
Extension = motion which increases the angle between 2bones
Hyperextension = increases the angle beyond normal inopposite of flexion.
Eversion – Toes outward
Inversion – Toes inward
Protraction – Straight outward from midline
Retraction – returning body to straight position