Deck 6: The Biomechanics of Human Skeletal Muscle

Question 1

The elasticity of human skeletal muscle tissue is believed to be due primarily to which of the following?

A)the parallel elastic component
B)the series elastic component
C)the continuous elastic component
D)the active elastic component

Answer 1

the series elastic component

Question 2

Which behavioral property of muscle tissue is defined as "the ability to respond to a stimulus"?

A)elasticity
B)irritability
C)extensibility
D)contractility

Answer 2

irritability

Question 3

Which type of muscle could serve as an antagonist of a flexor?

A)abductor
B)adductor
C)extensor
D)rotator

Answer 3

extensor

Question 4

Which of the following time periods is termed electromechanical delay?

A)the time required for conduction of the nerve impulse to the neuromuscular junction
B)the time required for the nerve impulse to cross the neuromuscular junction
C)the time required for the muscle to initiate the development of tension after receipt of the nerve impulse
D)the time required for a muscle to reach peak tension after the development of tension is initiated

Question 5

Which of the following types of muscle tension is commonly used as a braking mechanism to slow limb movement?

A)eccentric
B)isotonic
C)concentric
D)isometric

Question 6

Which of the following is a behavioral property of muscle tissue?

A)ability to develop tension
B)extensibility
C)irritability
D)all of these answers are correct

Question 7

Which of the following most accurately describes a motor unit?

A)a single muscle fiber and a single motor neuron
B)a single motor neuron and all muscle fibers it innervates
C)a single muscle fiber and several motor neurons
D)none of these answers is correct

Question 8

What type of muscle contraction is employed by the elbow flexors when slowly lowering your backpack to your desk?

A)concentric
B)eccentric
C)isometric
D)isokinetic

Question 9

A contraction in which there is not a change in length is called what?

A)dynamic
B)isometric
C)concentric
D)isokinetic

Question 10

Which of the following is true regarding the parallel elastic component (PEC)of muscular elasticity?

A)This component is provided by the muscle membranes.
B)This component provides resistance when a muscle is passively stretched.
C)This is the component primarily responsible for the elasticity of muscle.
D)Both this component is provided by the muscle membranes and this component provides resistance when a muscle is passively stretched.
E)All of these answers are correct.

Question 11

When flexing the elbow,the biceps brachii,brachioradialis,and brachialis are the three major agonists recruited to perform this movement because all cause flexion at the elbow. However,the biceps also cause supination,an undesired movement. Therefore another muscle acting as a ________,causing ________ must be recruited to prevent the undesired motion.

A)stabilizer; extension
B)neutralizer; extension
C)stabilizer; pronation
D)neutralizer; pronation

Question 12

Which of the following is a unique behavioral property of muscle tissue?

A)ability to develop tension
B)extensibility
C)irritability
D)all of these answers are correct

Question 13

Which of the following is/are characteristic of fast-twitch oxidative glycolytic fibers?

A)Contraction speed is intermediate (faster than type I but slower than type IIB).
B)Fatigue rate is intermediate (faster than type I but slower than type IIB).
C)Both contraction speed is intermediate (faster than type I but slower than type IIB)and fatigue rate is intermediate (faster than type I but slower than type IIB).
D)None of these answers is correct.

Question 14

Which of the following statements is true?

A)When movement is slow,slow twitch fibers are recruited first.
B)When movement is fast,fast twitch fibers are recruited first.
C)Both when movement is slow,slow twitch fibers are recruited first and when movement is fast,fast twitch fibers are recruited first are true.
D)None of these answers is correct.

Question 15

A muscle directly involved in causing a segment to move is called what?

A)agonist
B)antagonist
C)neutralizer
D)stabilizer

Question 16

A single muscle cell is called what?

A)fiber
B)neuron
C)unit
D)none of these answers are correct

Question 17

Which of the following is a potential disadvantage of multijoint muscles?

A)active insufficiency
B)passive insufficiency
C)both active insufficiency and passive insufficiency
D)none of these answers is correct

Question 18

When an opposing torque at a joint is greater than the torque created by a muscle,what type of contraction occurs in that muscle?

A)isometric
B)isotonic
C)concentric
D)eccentric

Question 19

Which of the following terms best describes the rate of torque production at a joint?

A)mechanical work
B)muscular power
C)muscular energy output
D)muscular strength

Question 20

Where is the series elastic component (SEC)of a muscle found?

A)tendons
B)ligaments
C)muscle membrane
D)all of these answers are correct

Question 21

Choose the term that describes "having the ability to stretch or shorten over time."

A)stretch-shortening cycle
B)summation
C)tetanus
D)viscoelastic

Question 22

Which of the following is true regarding the stretch-shortening cycle?

A)When a muscle is stretched just prior to contraction,the resulting contraction is more forceful.
B)An eccentric contraction is followed by a concentric contraction.
C)The SSC promotes storage of elastic energy.
D)Both when a muscle is stretched just prior to contraction,the resulting contraction is more forceful and an eccentric contraction is followed by a concentric contraction.
E)All of these answers are correct.

Question 23

During the first 12 weeks of resistance training,strength gains are due primarily to what?

A)improved innervation of the muscle
B)increase in cross-sectional area
C)both improved innervation of the muscle and increase in cross-sectional area
D)none of these answers is correct

Question 24

Choose the term that describes a fiber that reaches peak tension relatively quickly.

A)contractile component
B)eccentric
C)slow-twitch fiber
D)fast-twitch fiber

Question 25

The amount of torque a muscle group can generate at a joint is used to measure what?

A)muscular power
B)muscular endurance
C)muscular strength
D)muscular flexibility

Question 26

What role do the triceps play during the down phase of an arm curl exercise?

A)agonist
B)antagonist
C)stabilizer
D)neutralizer

Question 27

When the wrist is flexed,the finger flexors cannot produce as tight a fist as when the wrist is in a neutral position. This is an example of what?

A)active insufficiency
B)passive insufficiency
C)both active insufficiency and passive insufficiency
D)none of these answers is correct

Question 28

In human skeletal muscle,force generation capability is highest in which of the following conditions?

A)muscle is at resting length
B)muscle is slightly shortened
C)muscle is slightly lengthened
D)muscle length is irrelevant to force production

Question 29

The force-velocity relationship implies which of the following?

A)It is impossible to move a heavy resistance at a fast speed.
B)It is impossible to move a light load at a slow speed.
C)Both it is impossible to move a heavy resistance at a fast speed and it is impossible to move a light load at a slow speed.
D)None of these answers is correct.

Question 30

Choose the term that describes the state of muscle producing sustained maximal tension resulting from repetitive stimulation.

A)stretch-shortening cycle
B)summation
C)tetanus
D)viscoelastic

Question 31

Choose the term that describes the passive elastic property of muscle derived from the tendons.

A)pennate fiber arrangement
B)series elastic component
C)parallel elastic component
D)contractile component

Question 32

Choose the term that describes the pattern of fibers within a muscle with short fibers attaching to one or more tendons.

A)parallel fiber arrangement
B)passive insufficiency
C)pennate fiber arrangement
D)series elastic component

Question 33

The torque of a muscle (rotary component)is greatest in what position?

A)when the moment arm is longest
B)when the muscle insertion is 90° to the bone
C)both when the moment arm is longest and when the muscle insertion is 90° to the bone
D)position does not affect torque

Question 34

Which of the following is/are characteristic(s)of muscle fatigue?

A)reduction in muscle force
B)reduction in shortening velocity
C)prolonged relaxation of motor units between recruitment
D)both reduction in muscle force and reduction in shortening velocity
E)all of these answers are correct

Question 35

The increased force generation capability of a slightly stretched muscle is primarily due to which of the following?

A)series elastic component
B)parallel elastic component
C)golgi tendon organ
D)muscle spindle

Question 36

Choose the term that describes a contraction involving lengthening of a muscle.

A)antagonist
B)concentric
C)contractile component
D)eccentric

Question 37

Choose the term that describes the role played by a muscle acting to cause a movement.

A)active insufficiency
B)agonist
C)antagonist
D)concentric

Question 38

Choose the term that describes a single motor neuron and all fibers in innervates.

A)fast-twitch fiber
B)isometric
C)motor unit
D)neutralizer

Question 39

The opposite of muscular endurance is what?

A)muscular strength
B)muscular fatigability
C)muscular power
D)muscular flexibility

Question 40

Which of the following likely contributes to the stretch-shortening cycle?

A)the series elastic component
B)muscle spindle activity
C)both the series elastic component and muscle spindle activity
D)none of these answers is correct

Question 41

Choose the term that describes an inability of a two-joint muscle to stretch to the extent required to allow full range of motion at all joints.

A)passive insufficiency
B)pennate fiber arrangement
C)series elastic component
D)slow-twitch fiber

Question 42

Choose the term that describes the role played by a muscle acting to eliminate an unwanted action produced by an agonist.

A)fast-twitch fiber
B)isometric
C)motor unit
D)neutralizer

Question 43

A ________ muscle fiber reaches peak tension relatively slowly.

Question 44

Hamstring strains are slow to heal and have a high incidence of reoccurrence.

Question 45

Although muscle fibers are typically categorized by three types,there is actually a continuum of fiber characteristics.

Question 46

The ________ fiber arrangement is a pattern of fibers within a muscle with short fibers attaching to one or more tendons.

Question 47

There is good evidence that regular,lifelong,high-intensity exercise can reduce the loss of motor units typically associated with aging.

Question 48

A pattern of eccentric contraction followed immediately by concentric contraction is called ________ cycle.

Question 49

________ is a role played by a muscle to stabilize a body part against some other force.

Question 50

A muscle contraction which does not result in a change in length is called ________.

Question 51

Delayed onset muscle soreness is associated more with isometric training than with concentric or eccentric training.