Exam 1: Part 2 Flashcards
What is skeletal muscle responsible for?
Movement of body and all of its joints
Muscle contraction produces…
force that causes joint movement
What do muscles provide?
protection, dynamic stability of joints, posture & support
What is Aggregate muscle action?
muscles work in groups rather than independently to achieve a given joint motion
What are the 5 properties of force and movement of joints?
- irritability or excitability
- contractility
- extensibility
- elasticity
- plasticity
All muscles have a ____ that _____
nerve that stimulates it
What is irritability/excitability?
property of muscle being sensitive to chemical, electrical, and mechanical stimuli
What is contractility?
Ability of muscle to contract and develop tension or internal force against resistance when stimulated
What is extensibility?
A muscles ability to lengthen; ability of muscle to be passively stretched beyond it’s normal resting length
What is elasticity?
ability of muscle to return to its original length following stretching
What is plasticity?
ability of muscle to return to a new length following stretching
Intrinsic
pertaining usually to muscles within or belonging solely to body part upon which they act
Extrinsic
pertaining usually to muscles that arise or originate outside of (proximal to) body part upon which they act
ex: wrist and hand
Action
specific movement of a joint resulting from a concentric contraction of a muscle which crosses a joint
Innervation
segment of nervous system responsible for providing a stimulus to muscle fibers
Tendon
attaches a muscle to a bone
Origin
structurally, the proximal attachment and the least movable part
Insertion
Structurally, the distal attachment and the most movable part (usually always want to go towards the origin)
Contraction
when tension is developing in a muscle as a result of a stimulus
What do concentric contraction do?
Cause motion/movement; muscle shortens
What do eccentric contractions do?
Controls motion/movement; muscle lengthens
What type of contraction are both concentric and eccentric?
Isotonic contractions
T/F: All isotonic contractions work with the same muscle or same muscle groups
True
What do Isometric contractions do?
Prevent motion/movement; muscle length stays the same
What type of contraction are concentric and eccentric contractions?
Dynamic Contraction
What type of contraction is an isometric contraction?
Static Contraction
What’s the role of the agonist muscle?
Causes joint to move when it concentrically contracts
What’s another word for agonist muscles?
Prime move
What is the antagonist muscles location?
On the opposite side of the joint from the agonist
What’s the purpose of the antagonist muscle?
Suppose to relax to make agonist work
What’s the purpose of stabilizers?
Contract to fixate or stabilize an area to enable another limb to exert force and move
What does the synergist assist?
The agonist
What’s the purpose of the neutralizer?
counteracts the actions of another muscle to prevent undesirable movements
What is Reciprocal inhibition?
The antagonist muscles groups must relax and lengthen when the agonist muscle group contracts
What is active insufficiency?
When a muscle (agonist) cannot shorten any farther
What is passively insufficiency?
When the opposing muscle (antagonist) cannot stretch any farther
