Lecture Exam 1 (part 2) Flashcards
1
Q
List the 3 MF types
A
SO-slow twitch oxidative
FOG-Fast twitch oxidative glycolytic
FG-Fast twitch glycolytic
2
Q
Type naming for MFs
A
Type 1 (SO) Type 2a (FOG) Type 2b (FG)
3
Q
List how muscle fiber types differ (4)
A
Stimulus threshold for contraction
fiber type recruitment patterns
speed of contraction
structural differeneces
4
Q
Lowest stimulus threshold
A
SO
5
Q
Highest stimulus threshold
A
FOG, FG
6
Q
Fiber type recruitment is not this but this
A
speed related
intensity related
7
Q
Low intensity workouts us
A
SO
8
Q
Max intensity workouts use
A
FOG, FG, SO
9
Q
This increases the number of muscle fibers whos threasholds are met
A
increase in intensity
10
Q
most frequently recruited MF
A
SO
11
Q
Speed of contraction for ST, FT
A
110 ms
50 ms to contract
12
Q
four factors that contribute to speed of contraction
A
level of myosin ATPase
Myosin Isoforms
Development of SR
Troponin/Ca++ binding
13
Q
Myosin ATPase, these have low lvls, these have high lvls
A
ST
FT
14
Q
More ATPase =
A
faster contraction
15
Q
These can be used to determine muscle typing
A
myosin isoforms
16
Q
These fibers are not as effiecient in Ca++ release from SR
A
ST fibers
17
Q
This affects speed of cycle of myosin/actin binding
A
ST fibers have poor troponin/Ca++ binding affinity in relation to FT
18
Q
This are generally smaller than these
A
ST fibers
FT fibers
19
Q
T/F: FT fibers similar size
A
T
20
Q
indurence trained athletes have larger this than this due to specific training
A
ST
FT
21
Q
These are important in aerobic/oxidative ATP production
A
mitochondria
22
Q
This indicates the presence of many mitochondria in the cell
A
Oxidative
23
Q
FG don’t have mitochondria
A
F
24
Q
4 structural differences in between FT/ST
A
Size
mitochondria concentration
number of capillaries around
glycogen stores
25
This fiber types have many capillaries around them
SO
| FOG
26
this is a polymer of glucose, animal carbohydrate
glycogen
27
These fibers have large glycogen stores, these have smaller
FG and FOG
| SO
28
This fiber type do a good job of using fatty acids to produce energy
SO
29
difference in fiber innervation
smaller neurons innervate ST
| Larger neurons innervate FT
30
This characteristic of neurons is related to conduction velocity
diameter
31
Biochemical differences in MF types
```
myosinATPase concentration
hexokinase
phosphofructokinase
isocytrate dehydrogenase
mitochondrial enzyme activitiy
```
32
these are in higher concentration in glycolytic fibers
hexokinase
| phosphofructokinase
33
This compound effects speed of contraction
myosin ATPase
34
this puts glucose and glucose 6-phosphate together
hexokinase
35
this is the compound responsable for the rate limiting step of glycolysis
phosphofructokinase
36
These have more glycolytic enzymes than these
FG, FOG
| SO
37
All fibers can produce energy in these ways
aerobic
| anaerobic
38
this is the rate limiting enzyme in krebs cycle
isocytrate dehydrogenase
39
SO and FOG have more of these than FG
mitochondrial enzymes
40
These fibers are very versital in athletic events
FOG
41
these are more fatigue resistant but less powerful
oxidative fibers
42
this are generally more powerful/large
FT fibers
43
Different muscle in the same individual have this
different muscle fibers
44
this of the muscle dictate the general fiber type distribution patterns
functional demands
45
designed to determine if neuron dictates fiber type
cross innervation studies
46
cross innervation studies proved this
neuron dictates fiber type
47
Two hypotheses of how neuron dictates fiber type
use/disuse theory
| axoplasmic flow theory
48
neuron dictates stimulus threshold for contraction, fiber adapts to demands placed on it are ideas of this theory
use/disuse theory
49
unidentified chemical produced in body of LMN flows down the axon of the LMN and is released at the myoneural junction. Chemical tells fiber to take on characteristics of a given muscle fiber type
axoplasmic flow theory
50
Fiber type distribution patterns have the same in M/F
T
51
this is the ST/FT ratio in the vastas lateralis
1:1
52
in an individual the different muscles have different fiber type distribution.
T
53
What must we do when we say someone has more ST MF
specify the muscle groups
54
extremes in metabolic distribution means
substantial differeance in MF distribution patterns in different types of athletes
55
relationship between genotype/phenotype
genotype you are born that way
| phenotype is the result of exercise training
56
you cant convert from these two MF types, but you can in these types
ST to FT
FG to FOG fibers
stop training can turn FOG back to FG
57
Genotype/phenotype and how it relates to athletic performance in these two group types
heterogeneous group
| homogeneous group
58
genetic predisposition dictates athletic fitness
heterogeneous group, lower lvl athletics
59
phenotype predominates (diet,exercise), genotype is prerequisite
homogeneous group, highest lvl athletics
60
Factors that effect force production in a muscle (6)
```
# of fibers in an activiated motor unit
# of activated motor units
size of the muscle fiber
relationship between stimulation and inhibition
speed of movement
frequency of stimulation
```
61
Which factor of force production does the following represent: some have few, some may have up to 2-3000, more fibers = more force
of fibers in an activated motor unit
62
Which factor of force production does the following represent: as intensity increases we overcome the thresholds of more motor units
of activated motor units
63
Which factor of force production does the following represent: large MF stronger than small MF
size of the muscle fiber
64
Which factor of force production does the following represent: ACh for stimulation, inhibitory neurons at synapse release GABA at UMN and LMN junction.
relationship between stimulation and inhibition
65
Which factor of force production does the following represent: as velocity increases torque decreases
speed of movement effects force production
66
Which factor of force production does the following represent: firing rate of motor neuron
frequency of stimulation effects force production
67
under voluntary conditions we cannot always do this
activate all motor units
68
this can cause an increase in force past max exertion
electrical stimulation
69
initial strength increase in training is because of this
decrease in GABA activity
| seen in first 4-5 weeks as strength gains are not associated with size gains
70
relationship between stimulation and inhibition allows us to do this
control force with more precision
71
As this increases torque decreases
velocity
72
why does a faster movement reduce force
ST fibers cannot contract rapidly enough to keep up at high velocity muscle movement. Therefore force production of ST fibers is lost
73
describe the frequency of stimulation effect on force production
additive force effect when stimulation reoccurs before resting state
74
these modulate torque (2)
recruitment
| frequency (rate coding)
75
How does recrutiment modulate torque
as weight is increased recruitment of muscle fibers and motor units increases
increased freq. of rate stimulation also affected
76
name of the strategies that are affected by modulation of torque
motor unit-activation strategies or motor recruitment strategies
77
Some muscles rely more on this and some on this
rate coding
| recruitment
78
The more this the finer control of force production
rate coding
79
in an arm up to 80-90% of force is produced by this, the last 10-20% of force production capability is this
recruitment and frequency
| frequency (rate coding)
80
all of these muscle movements have different motor recruitment strategies for that type of force.
Isometric
concentric
eccentric
81
changes in the motor recruitment strategy is this when changing between muscle movements
instantaneous
82
this does not say will give all available force, only that at stimulus threshold a contraction with occur
all or none principle
