S/F Muscle One

Question 1

what is the end result of muscle force?

Answer 1

bone movement

Question 2

what is the fundamental unit of a muscle that creates force?

Answer 2

sacromere

Question 3

what are sacromeres in series called

Answer 3

myofibril

Question 4

what is a muscle cell called

Answer 4

fiber

Question 5

what surrounds a fiber

Answer 5

endomysium

Question 6

what is a group of fibers

Answer 6

fasicles

Question 7

what surrounds the fasicles

Answer 7

perimysium

Question 8

what surrounds the entire muscle

Answer 8

epimysium

Question 9

sliding filament hypothesis states that following electrical stimulation:

Answer 9

1 - myosin heads form rotating cross brides with actin filament
2 - actin is pulled over myosin

Question 10

__________ created is directly proportional to the number of simultaneously formed cross bridges

Answer 10

active force
(length tension relationship)

Question 11

what part of the sarcomere is the anchor point for actin and myosin filaments

Answer 11

Z line

Question 12

what part of the sarcomere is the anchor point for myosin (midpoint)

Answer 12

M-line

Question 13

what band only contains actin

Answer 13

I-band

Question 14

what shortens in the sarcomere during contraction

Answer 14

H and I band

Question 15

what part of the sarcomere contains myosin and only variable levels on actin

Answer 15

A-band

Question 16

what band only contains myosin and is located within A-band

Answer 16

H band

Question 17

what band does not change length with a muscle contraction

Answer 17

A band

Question 18

fusiform or strap muscles are built for

Answer 18

speed

Question 19

fusiform or strap muscle fibers are _________ with the tendon

Answer 19

parallel

Question 20

what is an example for fusiform or strap muscles

Answer 20

biceps or sartorius

Question 21

pennate muscles are built for_______

Answer 21

force

Question 22

pennate muscle fibers are _______ to the tendon

Answer 22

oblique

Question 23

example of unipennate muscles

Answer 23

tib post
semimembranosis

Question 24

example of bipennate muscles

Answer 24

gastroc
vmo
vi

Question 25

examples of multipennate muscles

Answer 25

deltoid, glute max

Question 26

what is additive shortening

Answer 26

muscle fibers with more sarcomeres in series shorten more increased shortening over similar time = increased velocity

Question 27

why do pennate muscles create more force

Answer 27

because there is not a 1:1 ratio between fiber length shortening and muscle length shortening. there is greater muscle fiber length shortening which adds up to increase the resultant force

Question 28

max force potential of a muscle is proportional to:

Answer 28

the sum of the PCSA of all its fibers (physiological cross sectional area)

Question 29

greater PCSA =

Answer 29

greater force development

Question 30

PCSA is greater for what muscle architecture

Answer 30

pennate muscle because it has an oblique angle

Question 31

passive length tension:

Answer 31

at some critical muscle length, increasing stretch results in storage of strain energy available to do work

Question 32

increased passive stiffness with:

Answer 32

increase length and increased velocity (viscoeleastic)

Question 33

active length-tension relationship

Answer 33

want there to be an appropriate amount of overlap between sarcomeres in order to produce optimal force

Question 34

what is the active contractile component of the hill type muscle model

Answer 34

actin myosin cross bridges

Question 35

what is the passive parallel elastic component of the hill type muscle model

Answer 35

- runs parallel to contractile proteins - connective tissue at z lines, endomysium, perimysium

Question 36

what is the passive series elastic component of the hill type muscle model

Answer 36

- joins end to end with contractile proteins - tendon and titin

Question 37

after an achilles tendon elongation repair, the typical elongation is 10-15%. what is this effect?

Answer 37

greater length (larger ROM) required to develop equivalent force

Question 38

passive insufficiency

Answer 38

multi joint muscle stretching will not allow full ROM at each joint crossed

Question 39

active insifficiency

Answer 39

multi joint muscle under active tension cannot produce force through available ROM at each joint crossed

Question 40

generally we experience reduced force of the agonist (__________) before resistance of the antagonist (_____________)

Answer 40

active insufficiency passive insufficiency

Question 41

T or F: force and power hit peak values under the same conditions

Answer 41

FALSE concentrically you cannot max both at the same time - greatest force produced when muscle does not change length - greatest speed produced under no load

Question 42

muscle produces greatest force when it:

Answer 42

does not change length

Question 43

muscle produces greatest speed when it is:

Answer 43

under no load

Question 44

linear power =

Answer 44

force x velocity

Question 45

angular power =

Answer 45

torque x angular velocity

Question 46

muscle force varies with contraction velocity. order from strongest to weakest

Answer 46

eccentric, isometric, concentric

Question 47

T or F: at a given force, concentric muscle contraction: - decreases metabolic cost - decrease CV load - decreases neural cost - decreases fatigue - increases DOMSr

Answer 47

false, eccentric does silly

Question 48

there is some evidence of potentially greater strength gains with ___________ overload training for the elderly, frail, and athletes alike

Answer 48

eccentric