Neuromuscular system and exercise cont. Flashcards
1
Q
resistance training
A
systematic program of exercises involving the exercises involving the exertion of force against a load used to develop strength, endurance, and/or hypertrophy of the muscular system
2
Q
CSEP and RT
A
beneficial to add muslce and bone strenthening activities using major muslce groups, at least 2 days/wk
3
Q
ACSM and RT
A
strenthening exercises at least twice a wekk for health related benefits of such exercises
4
Q
RT is used for 5
A
improving health - reduced risk of CV disease, type 2 diabetes, colon cancer, etc
injury rehab
improving athletic performance
improving dynamic stability and preserving functional capacity
changing physical appearance
5
Q
4 specificity in muscular fitness
A
muscular strength
hypertrophy
power
muscular endurance
6
Q
overload in muscular fitness is achieved by manipulating 4
A
load - amt of weight assigned to an exercise set
- % of 1RM
- most weight lifted for a specific # of reps
volume - load x reps x sets
rest intervals
frequency of training
7
Q
higher volumes are associated with
A
increases in muscle size
8
Q
load for muscular fitness 3
A
heavier loads - strength and power
mod for hypertrophy
light - endurance
9
Q
reps for muscular fitness
A
lowest to highest - power to strength to hypertrophy to endurance
10
Q
sets for muscular fitness
A
single set training may be appropriate for untrained ind. but higher volumes are necessary to promote further gains in intermediate and advanced participants
11
Q
rest interval
A
short rest periods utilized for building endurance
12
Q
frequency of training 3
A
novice - 2-3x/wk/muscle gp
intermediate 3-4
advanced 4-7
13
Q
RM for strength and power
A
2-7
14
Q
RM for hypertrophy
A
7-11
15
Q
RM for muscular endurance
A
13-20
16
Q
progression
A
increase in exercise stress - (intensity) once adaptation has occurred
- 2 for 2 rule - if 2 or more reps over the assigned goal can be performed in two consecutive workouts for a certain exercise, weight should be added to that exercise in the next training session
17
Q
rest/adaptation
A
1 day/muscle gp
18
Q
individualizaion
A
adaptation occurs at diff rates in diff ppl (genetic disposition)
19
Q
maintenacne
A
1 session/wk sufficient
20
Q
neuromuscular adaptations to RT (muscle function) -4
A
improve muscle strength and endurance by 25-100% with 2x/wk training
increased cross sectional area
both males and females are similar
regarless of age
21
Q
2 possible mechanisms for increased muscle size
A
hypertrophy - growth in cell size
hyperplasia - increase in the number of cells
hypertrophy for humans
22
Q
hypertrophy (3)
A
increase in muscle fibre cross sectional area
- increase myofilament content in myofibrils
- myofilament density - space between myosin filaments does not seem to be modified
23
Q
2 mechanisms of hypertrophy
A
signaling cascades leading to increased protein synthesis satellite cells (myosatellite) - muslce stem cells - located above the sarcolemma - quiescent unless activated can fuse with existing fibres
24
Q
myostatin
A
enhances muscle protein breakdown - limit skeletal muscle cell hypertrophy
25
cast induces muscle ___
atrophy
26
leucine and hypertrophy
activates mTOR which leads to hypertrophy
27
path of satellite cells
proliferative and commit to differentiation (myoblast) then fuse into myotube and mature into myofibre
28
myostatin related muscle hypertrophy
rare genetic mutation that prevents the body from producing myostatin - characterized by increased muscle size in ind with increased muscle strength and reduced subcutaneous fat pad thickness
29
myostatin inhibitors
not regulated so dont take it
30
anabolic steroids
synthetic substances related to the hormone testosterone that promote the growth of skeletal muscle as it binds to intracellular receptors to activate the DNA to dictate the synthesis of a protein
31
How to achieve greatest gains
androgen administration with RT
32
mechanism of hypertrophy
increased protein synthesis in skeletal muscle and activation of satellite cells
33
5 adverse side effects of anabolic steriods
CV disease - decreased HDL
endocrine: virilization, testis atrophy, prostatic hypertrophy, gynecomastia ( covertd into estrogen) , erectile dysfunction
liver: hepatitis, adenoma, carcinoma
musculoskeletal: premature epiphyseal plate closure, increase bone density, decrease tendon strength
psychiatric: aggressiveness, extreme mood swings- depression
34
virilizaton
females have male hair growth
35
gynecomastia
male breast development
36
hyperplasia in humans
hard to know - challenges directly measuring muscle fibers
37
hyperplasia in animals
RT
38
mechanisms of hyperplasia
satellite cells - form new fibers
| skeletal muscle fibre splitting - hypertrophied fibers break apart
39
hyperplasia in humans
young dead ppl - TA in dominant leg in young males had more muscle fibres than non dominant leg
increased cross sectional muscle area in powerlifters - not associated with increased muscle fiber size
- only in first years of life
40
can change in muscle size be longitudinal?
yes, increase or decrease the number of sarcomeres in series, if its contracted all the time, sarcomere gets removed and lose length
41
5 initial increases due to neural adaptation
increased CNS drive
increased synchronization of MU ( agonists, synergists)
enhanced coordination of MU - less resistance from antagonist muscle
increase in the size and number of motor end plates
reduced inhibition by reflexes
42
whats associated with the greatest neural adaptations?
high intensity (95-100% 1RM ) but does plateau - no change yet in actual muscle fiber
43
limb immobilization/suspension and ____ and ______ can lead to 4
spinal cord injury/space flight
- muscle atrophy (reduced CSA) - SO are the first to atrophy because they are the first to be activated
- muscle fiber type prfile goes from slow to fast twitch
- muscle oxidative capacity is reduced
- general weakness
44
can muscle fiber type change with training? (5)
minor modifications
not conversion, but the contractile properties and metabolic capacities can shift
modify their expression of myosin heavy chain
after extensive training
neural and structural modifications are much greater
you can only adapt - harder to become a FT
45
muscle fiber adaptation to RT for muscle size and structure -3
whole muscle and muscle fiber CSA
| myofibril protein content
46
connective tissue adaptation to RT - 3
increased collagen synthesis
portion of connective tissue to skeletal muslce
increased collagen stiffness
47
neural adaptation to RT - 3
increased MU recruitment
increased synchronization
decreased GTO reflex
48
metabolic adaptation to RT - 3
increased glycogen, PC, creatine phosphokinase
49
hormonal adaptations to RT - 3
inconsistent findingds for testosterone and cortisol
no change in GH
increase in insulin like growth factor
50
detraining and strength
strength is maintained longer than many other training adaptations - 15-30% decrease in strength reported with 30-32 weeks of detraining
51
muscular adaptations to aerobic enduracne training programs
increase in SO fibre size
| possible transition in FG to FOG
52
concurrent training
integration of endurance and resistance based training into a training program
53
strength gains and concurrent training
thin strength gains because the two rate of force pathways inhibit each other, one goes through IGF, then mTOR then translationsal activity then protein synthesis, the other goes through glycogen AMP then alpha 1 then mitochondrial biogensis for aerobic capacity
54
RT proves 6
reduced mortality, improved functional capacity and cardiometabolic health, strength, muscle mass, BMR
55
what improves insulin sensitivity?
aerobic training and RT
56
the nervous system
controls voluntary and involuntary movement - responsible for gross and find motor skills
57
somatic NS can be activated by
concsious thought and peripheral sensors
58
proprioception
perception of movement of body plus its orientation in space
59
proprioceptors aer located in
tendons, muslce and joints
- muscle spindles
- golgi tendon organ
60
cerebellum
integrate info from the somatic receptors, vestibular aparatus and visual and auditory stimuli
61
spinal cord receiving info
afferent info caried up the spinal column to the somatosensory cortex through ascending tracts - pain/nocireceptors
62
spinal cord sending info
alpha motor neurons are activated by pyramidal or extrapyramidal descending tracts
63
descending tracts (2)
pyramidal tract
| extrapyramidal tracts
64
pyramidal tract
voluntary corticospinal tract - neurons synapse directly onto alpha motor neurons
65
extrapyramidal tract
carries info that controls muscle tone and posture as well as head movements in response to visual stimuli and changes in equilibrium - indirect, polysynaptic pathway activation of an alpha motor neuron
66
direct synapse means
monosynaptic
67
muscle spindle furction and composition
proprioceptive stretch receptor
composed of fluid filled capsule
intrafusal muscle fiber and afferent neurons
68
intrafusal muscle fiber
nuclear bag fibers - thicker and attached to connctive tissue
nuclear chain fibers - thinner and shoter
69
afferent neurons
annulospiral - myelinated
- monitor rate of length change
flower spray sensory neurons - monitor relative muscle length and high threshold of excitation
70
alpha gamma motor neuron coactivation
when an alpha motor neuron is activated a gamma motor neuron is also activated to ensure that muslce spindle is always responsive
71
alpha motor neurons
activate extrafusal muscle fibres
72
gamma motor neurons
activate intrafusal muslcle fibres
73
reflex
rapid, involuntary response to stimuli in which a specific stimulus results in a specific motor response - does not require the higher brain centres but higher brain centers are informed
74
5 componenets of a reflex arc
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receptor
afferent sensory signal
integration center - processing of signal, integration with association neurons
efferent motor neuron
effector organ (skeletal muscle)
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75
reflexes can be ___ and ___
excitatory and inhibitory
76
myostatic stretch reflex
stretch stretch reflex
occurs with rapid ___ of a muscle, afferent impulses along the annulospiral neuron travel to the spinal cord, resulting in the activation of the agonist muslce and the reciprocal of the antagonist muscle (inhibited by neurotransmitters)
77
plyometrics
rapid stretches and stimulate the muscle spindels causing a reflexive muslce action to increases force production
78
asynchronized activation of alpha and gamma
gamma first, can be coordinated
79
golgi tendon organs
proprioceptors in the tendon of a muslce - monitors mucle tension
inverse myostatic - reciprocal activation to protect the muslce so it doesnt over tighten/contract -
80
inverse myostatic reflex
activated by muscle contraction and stretch, afferent signals travel to the spinal cord resulting in relaxation of the agonist muscle and reciprocal activation of the antagonist muslce
- protext the muscles and tendons from damage
81
untrained vs trained in plyometric training
kicks in much earlier than in untrained because you stretch - with eccentric, after training golgi woud be turned off and more power from contraction
82
volitional control for
```
important for skilled movement
function at the level of a single motor unit.
```
83
myoelectric prosthetic
take sensors to mount them on signals for them to take it and relay - train ind units -
84
volitional contraction of a muscle alters
muslce tension, length, and position ___
85
muscular changes due to volitional contractions are sensed by
receptors and transmitted to the central nervous system through afferent neurons
86
continual integration of this info and readjustments by the NS ensures
coordinated movement
87
flexibility
ROM in a joint or serioes of joints that reflects the ability of the musculotendon structures to elongate within the physical limits of the joint
88
3 types of stretching
ballistic stretching
static stretching
proprioceptive neuromuscular facilitation
89
ballistic stretching (3)
an action reaction bouncing motion, in which the jts involved are placed into extreme ROM by fast, active contractions of the agonistic muscle groups
activates myostatic stretch reflex
risks of injury
90
static stretching
muscle to be stretched slowly put into a position controlled maxiaml or near maximal stretch by contraction of the opposing muscle group and held for 30-60 seconds
- activates the inverse myostatic reflex if stretch continues for 6 seconds
91
proprioceptive neuromuscular facilitation
muscle to be stretched is first contracted maximally, then relaxed and either actively or passively stretched
- maximal contraction activates the inverse myostatic reflex - in the
92
why increase the agonist muscle when stretching
increase the ROM
93
physiological responses to stretching (2)
improves ROM
| before exercise may lead to performance deficits in strength, power, and reaction time
94
flexibility training (2)
does not limit strength, power, and reaction times - may contribute to reduced DOMS after eccentric dynamic exercise
95
does stretching and flexibility prevent injury?
no clear evidence
96
why does stretching help with eccentric dynamic exercise
longer muscles
97
take home msg for stretching
evidence on injury prevention, performance and health is not as strong as aerobic and RT - AT - RT - flexibility
98
what are all the factors that can affect muscle tension
```
genetics - fiber 1 and 2, 2 has more force
length tension
CNS drive - central farigue
Jt angle
Velocity of contraction - eccentric is neg velocity and has lots of force
hypertropy
elasticity
reflex
age, disease, injury, disuse
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