Muscular System Flashcards
Insertion
more movable bone
Origin
More stable bone
What do muscle names tell us?
- Location
- Shape
- Action
- Number of heads/divisions
- Attachments = origin/insertion
- Direction of fibers
- Size of muscles
Parallel muscle
fibers tend to be longer & have greater ROM potential
Oblique muscles
fibers tend to be shorter, but more numerous
Strap muscles
long and think with fibers running the entire length of the muscle
Fusiform muscles
shape similar to a spindle – wider in the middle and tapers at both ends
Rhomboidal muscle
4 sided, usually flat with broad attachments at each end
Triangular muscle
flat & fan shaped, with fibers radiating from a narrow attachment at one end to a broad attachment at another
Unipennate muscle
one side of a feather
Bipennate muscle
looks like a normal feather
Mulitpennate muscle
many tendons with oblique fibers in between
Normal resting length
length of a muscle when it is unstimulated
Irritability
ability to respond to a stimulus
Contractility
muscles ability to shorten or contact when it receives adequate stimulation
Extensibility
muscles ability to stretch or lengthen when force is applied
Elasticity
muscles ability to recoil or return to normal resting length when the stretching or shortening force is removed
Tension
force built up within a muscle
Excursion
distance fro maximum elongation to maximum shortening
Active insufficiency
muscle cannot shorten any further
Passive insufficiency
muscle cannot be elongated any further
Isometric Contraction
muscle contracts, but no movement in the joint
Isotonic contraction
muscle contracts, movement in the joint
2 types
concentric
eccentric
Concentric contraction
joint movement, muscle shortens
Eccentric contraction
joint movement, muscle lengthens
Agonist
prime mover
Antagonist
performs the opposite motion of the agonist
cocontraction
when the antagonist contracts at the same time as the agonist
Stabilizer
muscle or muscle group that supports, or makes firm, a part and allows the agonist to work more efficiently
Neutralizer
contracts to prevent unwanted motion
Synergist
muscle that works with one or more other muscles to enhance a particular motion
Closed kinetic chain
distal segment is fixed and proximal segment is open –
example: standing up from a sitting position
Open kinetic chain
distal segment is free to move while the proximal segment remain stationary
example: sitting and lifting your foot from the knee down
