Chapter 18: Muscle contraction and movement

Question 1

At what part of body lifts that female and male has distinguish different muscular strength?

Answer 1

upper body lift (bench press)

Question 2

Does the concentric contraction accelerate or decelerate? eccentric?

Answer 2

concentric contraction accelerate

eccentric contraction decelerate

Question 3

What muscle type that generate the greatest force? highest velocity?

Answer 3

pennate, bipennate, multipennate

parallel fibers in a fusiform manner

Question 4

What does the maximal velocity depend on?

Answer 4

the cycle rate of number cross bridges

Question 5

What does the maximal force depend on?

Answer 5

the number of cross bridges

Question 6

What determine the maximal number of cross bridges?

Answer 6

the sarcomere length (2-2.25)

Question 7

What does 1RM measure?

Answer 7

dynamic resistance strength

Question 8

Identify the three most probably causes of fatigue during short-term, high-intensity
anaerobic exercise.

Answer 8

depletion of PC stores
lactate interferes with cross-bridgings
accumulation of hydrogen ions

Question 9

Identify the three most probable causes of fatigue during long-term, moderate to
heavy, submaximal aerobic exercise.

Answer 9

depletion of glycogen
accumulation of hydrogen ions
lactate interferes with cross bridging

Question 10

What are the two uniques cause of muscle fatique in static exercise?

Answer 10

Occlusion of blood flow

Inhibition of motor cortex via sensory fibers in muscle

Question 11

What are the exercises use whole contraction of muscle?

Answer 11

dynamic, static and isokinematic exercise

Question 12

What is the dynamic exercise?

Answer 12

Exercise in which muscle forces vary as due to change of muscle length accordingly to the movement around joints

Question 13

Isotonic exercise

Answer 13

Exercise in which the muscle force is constant

Question 14

Isokinetic exercise

Answer 14

exercise in which velocity of contraction is constant

Question 15

Isokinematic exercise

Answer 15

exercise in which whole muscle contraction rate of limb displacement and joint is held constant

Question 16

Isometric exercise

Answer 16

exercise in which the length of muscle fiber is constant (velocity is zero)

Question 17

Static exercise

Answer 17

exercise in which there is no displacement or joints movement

Question 18

What exercise create the greatest force? least force?

Answer 18

eccentric dynamic exercise

concentric dynamic exercise

Question 19

what determine the force generated in muscle fibers?

Answer 19

neural factors ( frequency of stimulus and the recruitment of # of motor neurons)

Question 20

Length-tension relationship

Answer 20

The greatest force is generated is when at the optimal length of sarcomere (2-2.25)

Question 21

What happen when muscle fibers contract at optimal length?

Answer 21

the number of cross bridges are greatest

Question 22

Force-velocity relationship

Answer 22

the shortening velocity increases when the force decreases

Question 23

How does the muscle perform with prestretch?

Answer 23

muscle fibers generate greater force with prestretch without

Question 24

What happen when exercise damage the skeletal muscle?

Answer 24

It cause the leaking membrane, increase Ca2+, which degrade Z-disc and cause inflammation

Question 25

Treatment for DOMS?

Answer 25

Anti-inflammation drugs

Massage, Compression

Question 26

What is delay-onset muscle soreness?

Answer 26

the condition which you feel pain when palpate your muscle, occur 8hrs after exercise and peak from 24-48 hours and disappear after 96 hrs

Question 27

What are the laboratory methods to measure the muscular strength?

Answer 27

EMR: measure the motor units recruitment
Isokinetic: force, velocity, power
Force transducer: muscle static strength and endurance

Question 28

What cause the decline in muscle strength?

Answer 28

muscle mass degrade - 25% for both male and femal
loss of contractile properties of muscle fibers
reduced activation of motor units, denervation

Question 29

Does the ST lose more than FT when aging?

Answer 29

No, they are losing both equally