Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

FS Exam 2 > Force Regulation > Flashcards

Force Regulation Flashcards

1
Q

Discriminating Features of Muscle Types

A

Speed of Contraction (depends on ATPase - CB cycling)
Maximal Force Production (depends on # of CB)
Mechanical Efficiency (ATP produced for given force)
Oxidative Capacity (more mitochondria, more blood flow)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Fast vs. Slow Twitch

A

Type I = Slow Twitch/Slow Oxidative = SO
Type IIa = Fast Twitch/Fast Oxidative = FOG
Type IIx = Fast Twitch/Fast Glycolytic/Fast Fatigueable = FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Type I

A 
Slow Twitch - SO
Uses more oxygen, has more mitochondria
More myoglobin (binds ox to muscle)
Most fatigue resistant
Smaller motor unit, less mu strength, not innervating as many muscle fibers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Type IIa

A

Fast Twitch = FOG
Oxidative
More mitochondria, more oxidative fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Type IIx

A

Fast Twitch = FG
Greatest shortening velocity, Glycolytic
Produces most force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Why do slow twitch contract more slowly?

A

Myosin/ATPase, less developed SR, so less ATP is hydrolyzed at a time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why is slow twitch more fatigue resistant?

A

Higher oxidative enzymes, using mitochondria vs. glycolysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

ATPase Activity (least to most)

A

SO, FOG, FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Extensivity of SR (least to most)

A

SO, FOG, FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Motor Unites (least to most)

A

SO, FOG, FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Mitochondrial # (least to most)

A

FG, FOG, SO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Glycolytic Enzyme (least to most)

A

SO, FOG, FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Contractile Speed (least to most)

A

SO, FOG and FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Fatigability (least to most)

A

SO, FOG, FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Motor unit force (least to most)

A

SO, FOG and FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Nerve Conduction (least to most) - diameter of axon

A

SO, FOG and FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Efficiency (least to most)

A

FG, FOG, SO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Prevalance of fiber types

A

Typical Sedentary Indv.
50% SO
25% FOG
25% FG

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Skiing and Long Distance running trains what?

A

SO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Running 100 meters = which type?

A

Depends more on FG - doesnt require that much oxygen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Postural muscles, Diaphragm, and Intercostal = which type?

A

SO - we dont want them to fatigue

22
Q

Quad and Gastroc = which type

A

Fast and more power generating - FOG

23
Q

What determines fiber type?

A

Genetics - determines which motor nerve innervates individual fibers
Exercise Training - FOG will inc. with resistance and endurance training
Aging
Spaceflight - atrophy to postural muscles

24
Q

Muscle Fiber Recruitment

A

SO –> FOG –> FG

25
Q

Size Principle

A

MUs are recruited in order from smallest to largest (fewest to most fibers)

26
Q

Recruitment and Fatigability Relationship

A

Inversely related
SO first and least fatigable
More fibers are recruited as fibers in use start to fatigue

27
Q

Control of Muscle Force Production Depends on…

A

CB formation!

  1. MU recruitment (more MU, more force)
  2. MU firing rate (inc firing rate, inc force)
28
Q

Interaction of Firing and Recruitment in small vs. large muscles

A

Small muscles = more dependent on firing rate to generate force to get to max contraction
Larger muscles = can get to max contraction by recruitment more so than small muscles

29
Q

Force production begins with…

A

A twitch!

30
Q

Muscle Twitch phases

A
  1. Latent = AP to CB formation
  2. Contraction = beginning to peak tension or force generation
  3. Relaxation = Peak tension to no tension (when Ca is sequestered)
31
Q

Summation

A

Multiple twitches needed can summate
As frequency of stimulation increases, muscle cant fully relax so twitches summate until maximal (tetanic) contraction is reached

32
Q

Types of Muscle Contraction

A

Isometric
Isokinetic
Isotonic (Concentric and Eccentric)

33
Q

Isometric

A

no change in length, tension increases

Push against wall, static positions, postural muscles

34
Q

Isokinetic

A

Velocity at joint is constant

Need equipment to elicit

35
Q

Isotonic

A

Change in length, same tension
Concentric = shortening of muscle
Eccentric = lengthening of muscle (higher max forces can be generated, more soreness)

36
Q

Length Tension Relationship

A

Max force occurs at length of optimal myosin and actin overlap
This typically occurs at the normal resting muscle length

37
Q

Length and Passive Tension

A

Passive - depends on CT
No contraction involved
As muscle is stretched, tension develops (preload)
More stretch = more passive elements are activated
Stretch 2-3% of resting length with application of load

38
Q

Stretch Shortening Cycle

A

Box Jumps
Rapid coupling of Eccentric –> Concentric
Storage of elastic energy in ecc phase is then released in conc phase
Enhance CB activity via preload effect

39
Q

Factors Affecting SSC

A

dissipates with increased duraction btw ecc and conc

Inc in stretch velo = inc in storage of elastic energy

40
Q

Muscle Length vs. Tension in Active vs. Passive

A

Active = reflects CB formation
Passive = reflects elastic elements
Total tension = active + passive

41
Q

Force and Velocity Relationship

A

Inverse relationship

As load increases, the velocity of shortening will decrease

42
Q

As rate of contraction increases, what happens to force? Why?

A

Decreases

Because less time for CB formation

43
Q

Force at any given velocity is _____ in fast twitch muscle? Why

A

Greater

Faster myosin ATPas activity and more Ca released from SR

44
Q

Force Power Relationship

A

Peak power is at 20 or 30% of fiber peak force

At 100% peak force, you have no power, not going anywhere

45
Q

Agonist

A

primary mover

46
Q

Antagonist

A

opposes the prime mover

47
Q

Synergist

A

facilitates action of prime mover

48
Q

Co-Contraction

A

simultaneous activation of agonist and antagonist

49
Q

Active Insufficiency

A

muscle cant produce or maintain active tension because it is too long or too short
Flexion of elbow and shoulder
ROM inhibited by agonist

50
Q

Passive Insufficiency

A

Length of antagonist is not long enough to allow agonist to further increase ROM
ROM inhibited by the antagonist

FS Exam 2 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions