Muscular System Ch 5 Flashcards
What is another name to describe the distal attachment?
Insertion
What is another name to describe the proximal attachment?
Origin
What is the term for the situation in which a muscle contracts until it can contract no farther even through more joint range of motion is possible?
Active insufficiency
Is walking downhill a concentric or eccentric contraction of your quadriceps muscle?
Eccentric
Identify the following in terms of open or closed kinetic chain exercises?
A. Wheelchair push ups?
B. Exercises with weight cuffs?
C. Overhead wall pulleys?
Wheelchair push ups = closed
Exercises with weight cuffs = open
Overhead wall pulleys = open
What position would a person have to be in to perform shoulder abduction and adduction in a gravity eliminated position?
Supine or prone lying
The rectus femoris flexes the hip and extends the knee. The vastus medialis extends only the knee. In what position must the hip and knee be place to be able to stretch the vastus medialis?
Hip flexed to place the rectus femoris on slack w/ the knee flexed
If you wanted a muscle to lift a very strong load, what muscle fiber arrangement would you want?
Oblique
If you wanted a muscle to contract through a very great range, what muscle fiber arrangement would you want?
Parallel
Describe parallel muscle?
Longer muscle fibers w/ greater ROM potential
Describe oblique muscle?
Shorter muscle fibers
Greater strength potential
Smaller ROM
More numerous per given area than parallel fibers
What shapes can parallel fibered muscles be?
Strap
Fusiform
Rhombodial (rectangular)
Triangular
Describe the characteristics of a strap shaped muscles? Give examples of some?
Long and thin with fibers running the length of the muscle
ie- sartorius, rectus abdominis, SCM
Describe the characteristics of a fusiform shaped muscles? Give examples of some?
Wider in the middle and tapers are both ends where it attaches to the tendon
Most but not all fibers run the length of the muscle
Can be long or short, large or small
ie- biceps, brachialis, brachioradialis
Describe the characteristics of a rhomboidal shaped muscles? Give examples of some?
Four sided, usually flat w/ broad attachment at each end
ie- pronator quadratus, rhomboids, gluteus maxius
Describe the characteristics of a triangular shaped muscles? Give examples of some?
Flat and fan shaped w/ fibers from a narrow attachment to one end to a broad attachment at the other
ie- pec major
Describe the characteristics of a unipennate shaped muscles? Give examples of some?
One sided feather
A series of short fibers attaching diagonally along a central tendon
ie- semimembranous, tibialis posterior, flexor pollicis longus of hand
Describe the characteristics of a bipennate shaped muscles? Give examples of some?
A feather
Fibers area obliquely attached to both sides of a central tendon
ie- rectus femoris and interossei
Describe the characteristics of a multipennate shaped muscles? Give examples of some?
Have many tendons w/ oblique fibers in between
ie- deltoid and subscapularis muscles
What refers to the force built up within a muscle?
Tension
What is the length of a muscle when it is unstimulated?
Normal resting length
What is irritability?
The ability to respond to a stimulus
This is the muscle’s ability to shorten or contract when it receives adequate stimulation?
Contractility
What is the muscles ability to stretch or lengthen when a force is applied?
Extensibility
What is elasticity?
The muscle’s ability to recoil or return to normal resting length when the stretching or shortening force is removed
What is slight tension that is present in a muscle at all times?
Tone
Name the term that describes the distance from maximum elongation to maximum shortening?
Excursion
When is a muscle at its strongest?
When it is put on stretch prior to contracting
When does passive insufficiency occur?
Occurs when a muscle can not be elongated any farther without damage to its fibers
Which type of contraction occurs when a muscle contracts and the muscle length and joint angle changes?
Isotonic contraction
Which type of contraction occurs when there is joint motion but the muscle appears to lengthen?
Eccentric contraction
Which type of contraction occurs when a muscle contracts producing force without changing the length of muscle?
Isometric contraction
Which type of contraction occurs when there is a joint movement , the muscles shorten and the muscle attachments move towards each other?
Concentric contraction
Describe an isokinetic contraction?
Resistance varies, if the person pushes harder the machine will give more resistance
Speed is preset and stays the same
ie- cybex orthotron machine is used to produce isokinetic contractions
What is a muscle or muscle group that causes the motion? What else could it be referred to as
agonist
prime mover
What is a co-contraction?
When the antagonist contracts at the same time as the agonist
Provides joint stabilization during normal movement
What is a muscle that assists in providing motion?
Assisting mover
What is an antagonist? Give an example?
A muscle that performs the opposite motion of the agonist
Elbow flexion: triceps = antagonist/ biceps = agonist
What is a stabilizer? Give an example?
A muscle or muscle group that supports a part and allows the agonist to work more efficiently.
ie- in a push-up
Agonist = elbow extensor muscles
Stabilizers = abdominal muscles keep the trunk straight while the arms move the trunk up and down
What is a neutralizer?
If a muscle can do two or more actions but only one is wanted a neutralizer contracts to prevent unwanted motions
Give an example of a neutralizer?
Biceps can FLEX elbow and SUPINATE the forearm, if elbow flexion is wanted, to rule out the supination motion, the pronator teres muscle contracts to counter act supination
What is a muscle that works with one or more other muscles to enhance a particular motion?
Synergist
What is a closed kinetic chain?
Distal segment is fixed (closed) and proximal segment moves
Closed chain exercises work multiple joints and multiple muscle groups at once
ie- push ups, , pull-ups, rowing machine, stationary bike, and stair stepper, mini squats, wall slides, lunges
What is a open kinetic chain?
Distal segment is free to move while the proximal segment is fixed
These types of movements tend to isolate a single muscle group and a single joint
ie- seated knee extension or flexion, dumbbell chest press, bicep curls
