exam 2 practice exams multiple choice
Lab X
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Which of the following best describes the hold relax with agonist contraction PNF procedure if the goal is to improve stretch of the gastrocnemius muscle?
-We stretched the subject's gastrocnemius passively until we reached the limits of its ROM. -Then we had the subject contract their gastrocnemius submaximally and then maximally while we held their foot in place -then had them relax while we pushed their foot further while the subject contracts their dorsiflexor muscles
Which of the following fiber types would tend to have the highest PFK (phosphofructokinase) activity?
IIX
Which of the following torque curves looks most like the torque curve we recorded for the hamstrings on the Biodex in lab (video)?
K (parallel/plateau)
___________________________________ is related to the orderly recruitment of motor units from most aerobic to least aerobic
size principle
Which of the following would produce the greatest torque?
eccentric knee extension 90 deg/sec
The following figure depicts EMG and iEMG activity during dynamic bicep curls until the subject could not lift the weight anymore. They lifted the weight 17 times before they fatigued. Which of the following mechanism(s) are most likely to be contributing this fatigue, given this set of data?
reduced force by each cross bridge
Which of the following best describes the hold relax with agonist contraction PNF procedure if the goal is to improve stretch of the hamstrings?
-We stretched the subject's hamstring passively until we reached the limits of its ROM. -Then we had the subject contract their hamstrings submaximally and then maximally while we held their leg in place -then had them relax while we pushed their leg further while the subject contracts their quadriceps muscles
Which of the following torque curves looks most like the torque curve we recorded for the quadriceps femoris on the isokinetic device in lab?
L (only peak/hump)
Which of the following EMG tracings best depicts the electrical activity of a muscle group moving a 25 pound weight and has a very very good overlap of actin and myosin at 135?
L (v shape)
The EMG data below was collected during a variety of activities from the abdominal muscles (abs) and from the rectus femoris (hip flexors). Which of the following exercises best activates the abdominal muscles?
two of these are equally good
How much power is produced when performing an isometric bicep curl, your subject held a/n 33 pound weight a distance of 0.28 meters off the floor for 0.43 seconds. No units required
0
Which of the following fiber types would tend to have the lowest ATPase activity?
I
Which of the following fiber types would tend to have the lowest amount of SERCAs?
I
Which of the following fiber types would tend to have the lowest amount of glycolytic enzymes?
I
Which of the following fiber types would tend to have the lowest mitochondrial volume?
IIX
Which of the following fiber types would tend to store the least intramuscular triglycerides (lipids)?
IIX
In our recent lab we did experiments related to several aspects of muscle performance including force, velocity, power, and muscle length. Which of the following figures best depicts the force-velocity curve during concentric and eccentric actions?
L
The far left panel depicts the torque curve for a muscle group performing an eccentric action. Which of the other curves best represents the torque curve you would expect to see for this same muscle group during a concentric action?
L (smallest hump)
The EMG tracing on the far left was recorded from a muscle group during a single concentric action with free weights. You then tested this same muscle group on an isokinetic dynamometer. Which of the figures best depicts the torque curve we would observe for this muscle during this isokinetic action? (green is shaded V shape
L (up hump)
Which of the following EMG tracings best depicts the electrical activity of a muscle group with the best leverage at 135 while performing a knee extension with free weights?
L (v shape)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Which point on this curve would probably be associated with the highest concentric forces?
L first dot after line on right
The torque curve on the far left was recorded from a muscle group during a single concentric isokinetic action. You then recorded the EMG of this same muscle group using free weights during a single concentric action. Which of the figures best depicts the EMG tracing we would observe for this muscle during this lift?
M (upside down V)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Considering all labelled data points on this curve, which has the lowest potentnial for producing power?
N (center point)
Which of the following EMG tracings best depicts the electrical activity of a muscle group that has its poorest leverage at 90?
N (diagnol down to right)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Considering all labelled data points on this curve, which has the lowest potentnial for producing power?
N (dot on the line)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Considering all Concentric data points on this curve, which likely has the greatest potentnial for producing power?
N (third dot from line on the right)
The EMG tracing on the far left was recorded from a muscle group during a single concentric action with free weights. You then tested this same muscle group on an isokinetic dynamometer. Which of the figures best depicts the torque curve we would observe for this muscle during this isokinetic action?
N (upside down U)
In our recent lab we did experiments related to several aspects of muscle performance including force, velocity, power, and muscle length. Which of the following figures best depicts the length-passive tension curve?
O (decrease to increase normal looking slope)
Which of the following EMG tracings best depicts the electrical activity of a muscle group performing a 3 second isometric action (ignore joint angles listed below figures)?
O (square shaded box)
In our recent lab we did experiments related to several aspects of muscle performance including force, velocity, power, and muscle length. Which of the following figures best depicts the length-tension Total tension curve?
O (upwards graph that cuts off)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Low speed resistance training would increase which concentric data point the most?
O second dot from the line on concentric
Which of the following torque curves best depicts the resistance during a single concentric bicep curl with a 20 lb weight?
O straight across line
Which of the following would have the highest EMG activity with a 20 pound weight?
concentric action with low force arm:resistance arm ratio'
Which of the following would require the greatest recruitment of motor units with a 20 pound weight?
concentric action with poor leverage
Which of the following would have the highest EMG integral with a 20 pound weight at mid flexion (~90degrees)?
concentric action with poor overlap of actin and myosin
Which of the following would require the most motor unit recruitment when using a 15 lb weight?
concentric bicep curl with forearm supinated moving at 30 degrees per second
If you were performing a hold relax with agonist contraction PNF procedure to try to improve hamstring flexibility, which of the following muscles/muscle groups would we contract during the second phase of this procedure?
quadriceps femoris
The following figure depicts EMG and iEMG activity during dynamic bicep curls until the subject could not lift the weight anymore. They lifted the weight 17 times before they fatigued. Which of the following mechanism(s) are LEAST likely to be contributing this fatigue, given this set of data?
reduced calcium release from the sarcoplasmic reticulum
The following figure depicts EMG and iEMG activity during dynamic bicep curls until the subject could not lift the weight anymore. They lifted the weight 17 times before they fatigued. Which of the following mechanism(s) are LEAST likely to be causing this fatigue, given this set of data?
reduced excitability in motor areas of the cerebral cortex
The following figure depicts EMG and iEMG activity during dynamic bicep curls until the subject could not lift the weight anymore. They lifted the weight 17 times before they fatigued. Which of the following mechanism(s) are most llikely to be contributing this fatigue, given this set of data?
reduced excitability in motor areas of the cerebral cortex
In lab one of our experiments looked at the effects of velocity and type of action (concentric, eccentric, isometric) on the abiltiy to produce force during knee extension and flexion exercise on an isokinetic dynamometer. The figure below depcits some of this data. Match the points on the figure with the best descriptions below.
the axis that represents the torque K velocity of 0 degrees/second M concentric velocity of 300 degrees/second L The curve for the extensor muscles P The curve for the flexor muscles O
In lab one of our experiments looked at the effects of velocity and type of action (concentric, eccentric, isometric) on the abiltiy to produce force during knee extension and flexion exercise on an isokinetic dynamometer. The figure below depcits some of this data. Match the points on the figure with the best descriptions below.
the axis that represents the torque P axis that represents velocity J eccentric velocity of 90 degrees/second M speed 0 degrees/second N concentric velocity of 300 degrees/second. O
In lab one of our experiments looked at the effects of velocity and type of action (concentric, eccentric, isometric) on the abiltiy to produce force during knee extension and flexion exercise on an isokinetic dynamometer. The figure below depcits some of this data. Match the points on the figure with the best descriptions below.
the axis that represents velocity Q velocity of 0 degrees/second M eccentric velocity of 90 degrees/second N The curve for the extensor muscles P The curve for the flexor muscles O
During our "jumping" experiment we had our subject jump with or without a counter-movement, and we also had our subject perform some "drop jumps". We recorded EMG activity from the vastus lateralis and jump height during each. Here are some sample results from these experiments. What is a likely explanation for the increase in jump height between the counter movement jump and the 0.25m drop jump? 16,14,19,17
the initiation of a stretch reflex
___________________________________ is when more motor units are stimulated more frequently to produce more force.
twitch summation
Which of the following changes would cause the biggest increase in Torque?
knee extensors going from 300 deg/sec to 30 deg/sec
Which of the following changes would cause the smallest increase in Torque?
knee flexors going from 300 deg/sec to 30 deg/sec
When we perform a counter-movement to try to jump higher, one possible mechanism for this improvment in jump height might be tied to activating which of the following proprioreceptors?
muscle spindles
The far left panel depicts the torque curve for a muscle group performing a concentric action. Which of the other curves best represents the torque curve you would expect to see for this same muscle group during an eccentric action?
n (biggest peak)
Which of the following would require the least amount of motor unit recruitment with a 15 lb weight?
eccentric bicep curl 30deg/sec
Which of the following would have the lowest iEMG integral when using a 15 lb weight?
eccentric bicep curl with forearm pronated moving at 90 degrees per second
Which of the following would produce the greatest force?
knee extensors 30 degrees/second
Which of the following changes would cause the biggest decrease in Torque?
knee extensors going from 30 deg/sec to 300 deg/sec
The following figure depicts EMG and iEMG activity during dynamic bicep curls until the subject could not lift the weight anymore. They lifted the weight 17 times before they fatigued. Which of the following mechanism(s) are most llikely to be contributing this fatigue, given this set of data?
low dopamine levels in motor areas of the brain
The following figure depicts EMG and iEMG activity during dynamic bicep curls until the subject could not lift the weight anymore. They lifted the weight 17 times before they fatigued. Which of the following mechanism(s) are LEAST likely to be contributing this fatigue, given this set of data?
low pH inhibiting PFK, which would reduce ATP production
If we observed an increase in EMG amplitude when our subject lifted a heavier weight, this would be evidence of what type of summation?
multiple motor unit summation
___________________________________ is related to the orderly recruitment of motor units from lowest threshold to highest threshold
size principle
Which of the following fiber types would be most resistant to fatigue?
I
Which of the following fiber types would have the lowest frequency required to achevie tetanus?
I
Which of the following fiber types would tend to be recruited first?
I
Which of the following fiber types would tend to have the greatest capillary density?
I
Which of the following fiber types would tend to have the largest twitch time (highest number if we gave it a numeric value)?
I
Which of the following fiber types would tend to store the least glycogen?
I
Which of the following fiber types would tend to be the largest diameter fibers in men?
IIA
Myosin heavy chain IIA and Myosin heavy chain I would both be found in which fiber type?
IIC
Myosin heavy chain IIX would be the predominant type of myosin in which fiber type?
IIX
Which of the following fiber types would tend to store the most glycogen?
IIX
Which of the following EMG tracings best depicts the electrical activity of a muscle group that has its sticking point at 180?
K ( straight up)
Which of the following EMG tracings best depicts the electrical activity of a muscle group that has its sticking point at 180?
K (diagnol down to left)
Which of the following torque curves best depicts the expected torque curve for a flexor muscle group?
K (parallel)
Which of the following torque curves best depicts the expected torque curve we would expect for a muscle group with long muscle fibers?
K (parallel, goes up plateau and goes down)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. High speed resistance training would increase which concentric data point the most?
O (last pt concentric)
During the second phase of the hold-relax with agonist contraction procedure to try to increase the stretch of a muscle we make use of which of the following reflex phenomena?
reciprocal inhibition
Your subject is an 25 year old female who weighs 190 lbs. You previously determined that her maximal voluntary contraction force was 33 lbs and her iEMG integral during the MVC was 0.000213. During lab today you had her hold a 16 pound weight isometrically for a few seconds and her integral during this lift was 0.000090. What is her normalized iEMG activity for this lift?
42.3
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Considering all labelled data points on this curve, which has the lowest potentnial for producing power?
L (center point)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Considering all labelled data points on this curve, which has the greatest potentnial for producing power?
L (first pt eccentric)
The EMG tracing on the far left was recorded from a muscle group during a single concentric action with free weights. You then tested this same muscle group on an isokinetic dynamometer. Which of the figures best depicts the torque curve we would observe for this muscle during this isokinetic action?
L (normal hump)
Which of the following torque curves best depicts the expected torque curve we would expect for a muscle group with short muscle fibers in a pennate arrangement?
L (normal hump)
In our recent lab we did experiments related to several aspects of muscle performance including force, velocity, power, and muscle length. Which of the following figures best depicts the length-total tension curve?
M
Which of the following EMG tracings best depicts the electrical activity of a muscle group that has a very low force arm:resistance arm ratio at 135?
M (rollar coaster up down)
In our recent lab we did experiments related to several aspects of muscle performance including force, velocity, power, and muscle length. Which of the following figures best depicts the passive length tension curve?
N
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. If we were comparing knee extensors and knee flexors, the extensors would be most likely to have higher force production at which concentric data point?
O (second dot from line to the right)
Which of the following EMG tracings best depicts the electrical activity when performing an isokinetic knee extension (best leverage around 135)?
O (shaded straight across)
In our recent lab we did experiments related to several aspects of muscle performance including force, velocity, power, and muscle length. Which of the following figures best depicts the length-active tension curve?
P (normal hump but weird breaks)
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Why does point O have such a low value on this figure?
This is a power-velocity curve, and at that point velocity is zero, and since power = F x velocity, power would be zero
Which of the following would require the most EMG activity?
all would be the same
The following figure depicts EMG and iEMG activity during dynamic bicep curls until the subject could not lift the weight anymore. They lifted the weight 17 times before they fatigued. Which of the following mechanism(s) are LEAST likely to be contributing this fatigue, given this set of data?
an increase in Pi inside the muscle fibers
Which of the following would have the highest EMG integral with a 20 pound weight?
concentric action with low force arm:resistance arm ratio
Which of the following would have the highest iEMG integral?
concentric action with low force arm:resistance arm ratio
Which of the following would produce the least force?
concentric action with low force arm:resistance arm ratio
Which of the following would require the greatest number of motor units to be recruited?
concentric action with low force arm:resistance arm ratio
If you were performing a hold relax with agonist contraction PNF procedure to try to improve gastrocnemius flexibility, which of the following muscles/muscle groups would we contract as during the second phase of this procedure?
dorsiflexors (e.g. tibialis anterior andextensor diegitorum longsus)
If you were performing a hold relax PNF procedure to try to improve hamstring flexibility, which of the following muscles/muscle groups would we contract as a part of this procedure?
hamstrings
If you were performing a hold relax with agonist contraction PNF procedure to try to improve hamstring flexibility, which of the following muscles/muscle groups would we contract during the first phase of this procedure?
hamstrings
During the first phase of the hold-relax with agonist contraction procedure to try to increase the stretch of a muscle we make use of which of the following reflex phenomena?
inverse stretch reflex
When using the hold-relax with agonist contraction procedure to try to increase the stretch of a muscle we make use of which of the following reflex phenomena?
inverse stretch reflex and reciprocal inhibition
Which of the following would produce the most torque?
isokinetic knee extension mid-extension (125-135 deg)
Which of the following would have the lowest EMG integral when using a 15 lb weight?
isometric action with high force arm:resistance arm ratio
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Why does point M have a high value on this figure? (top of concentric peak)
power is high; intermediate velocity and force provides the best combination for producing power
in lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. Why does point M have a high value on this figure?
power is high; intermediate velocity and force provides the best combination for producing power
When we perform a counter-movement to try to jump higher, one possible mechanism for this improvment in jump height might be tied to activating which of the following reflexes?
stretch reflex
If motor units are stimulated frequently enough we will observe no relaxation between twitches, this is called ____________________________
tetanus
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. How would a muscle with more FT fibers compare to this subject at point Q? (top of concetric peak)
the subject with more fast twitch fibers would have higher values
Which of the following isokinetic actions would have the highest EMG integral?
they would all be about the same
In lab we collected data related to force-velocity and power-velocity relationships. One such set of data is presented graphically below. How would a muscle with more FT fibers compare to this subject at point O? (bottom in middle of ecentric/concentric on the line)
they would be about the same
What is the goal of hold relax and hold relax with agonist contraction PNF procedures if you were trying to improve hamstring flexibility? select the single best answer
to inhibit hamstring muscle contraction so that the muscle cna be stretched further
Which of the following would produce the least torque?
eccentric knee extension 30deg/sec
