Neuromuscular system and exercise cont. Flashcards Preview

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Flashcards in Neuromuscular system and exercise cont. Deck (98)
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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
Q

cast induces muscle ___

A

atrophy

26
Q

leucine and hypertrophy

A

activates mTOR which leads to hypertrophy

27
Q

path of satellite cells

A

proliferative and commit to differentiation (myoblast) then fuse into myotube and mature into myofibre

28
Q

myostatin related muscle hypertrophy

A

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
Q

myostatin inhibitors

A

not regulated so dont take it

30
Q

anabolic steroids

A

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
Q

How to achieve greatest gains

A

androgen administration with RT

32
Q

mechanism of hypertrophy

A

increased protein synthesis in skeletal muscle and activation of satellite cells

33
Q

5 adverse side effects of anabolic steriods

A

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
Q

virilizaton

A

females have male hair growth

35
Q

gynecomastia

A

male breast development

36
Q

hyperplasia in humans

A

hard to know - challenges directly measuring muscle fibers

37
Q

hyperplasia in animals

A

RT

38
Q

mechanisms of hyperplasia

A

satellite cells - form new fibers

skeletal muscle fibre splitting - hypertrophied fibers break apart

39
Q

hyperplasia in humans

A

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
Q

can change in muscle size be longitudinal?

A

yes, increase or decrease the number of sarcomeres in series, if its contracted all the time, sarcomere gets removed and lose length

41
Q

5 initial increases due to neural adaptation

A

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
Q

whats associated with the greatest neural adaptations?

A

high intensity (95-100% 1RM ) but does plateau - no change yet in actual muscle fiber

43
Q

limb immobilization/suspension and ____ and ______ can lead to 4

A

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
Q

can muscle fiber type change with training? (5)

A

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
Q

muscle fiber adaptation to RT for muscle size and structure -3

A

whole muscle and muscle fiber CSA

myofibril protein content

46
Q

connective tissue adaptation to RT - 3

A

increased collagen synthesis
portion of connective tissue to skeletal muslce
increased collagen stiffness

47
Q

neural adaptation to RT - 3

A

increased MU recruitment
increased synchronization
decreased GTO reflex

48
Q

metabolic adaptation to RT - 3

A

increased glycogen, PC, creatine phosphokinase

49
Q

hormonal adaptations to RT - 3

A

inconsistent findingds for testosterone and cortisol
no change in GH
increase in insulin like growth factor

50
Q

detraining and strength

A

strength is maintained longer than many other training adaptations - 15-30% decrease in strength reported with 30-32 weeks of detraining

51
Q

muscular adaptations to aerobic enduracne training programs

A

increase in SO fibre size

possible transition in FG to FOG

52
Q

concurrent training

A

integration of endurance and resistance based training into a training program

53
Q

strength gains and concurrent training

A

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
Q

RT proves 6

A

reduced mortality, improved functional capacity and cardiometabolic health, strength, muscle mass, BMR

55
Q

what improves insulin sensitivity?

A

aerobic training and RT

56
Q

the nervous system

A

controls voluntary and involuntary movement - responsible for gross and find motor skills

57
Q

somatic NS can be activated by

A

concsious thought and peripheral sensors

58
Q

proprioception

A

perception of movement of body plus its orientation in space

59
Q

proprioceptors aer located in

A

tendons, muslce and joints

  • muscle spindles
  • golgi tendon organ
60
Q

cerebellum

A

integrate info from the somatic receptors, vestibular aparatus and visual and auditory stimuli

61
Q

spinal cord receiving info

A

afferent info caried up the spinal column to the somatosensory cortex through ascending tracts - pain/nocireceptors

62
Q

spinal cord sending info

A

alpha motor neurons are activated by pyramidal or extrapyramidal descending tracts

63
Q

descending tracts (2)

A

pyramidal tract

extrapyramidal tracts

64
Q

pyramidal tract

A

voluntary corticospinal tract - neurons synapse directly onto alpha motor neurons

65
Q

extrapyramidal tract

A

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
Q

direct synapse means

A

monosynaptic

67
Q

muscle spindle furction and composition

A

proprioceptive stretch receptor
composed of fluid filled capsule
intrafusal muscle fiber and afferent neurons

68
Q

intrafusal muscle fiber

A

nuclear bag fibers - thicker and attached to connctive tissue
nuclear chain fibers - thinner and shoter

69
Q

afferent neurons

A

annulospiral - myelinated
- monitor rate of length change
flower spray sensory neurons - monitor relative muscle length and high threshold of excitation

70
Q

alpha gamma motor neuron coactivation

A

when an alpha motor neuron is activated a gamma motor neuron is also activated to ensure that muslce spindle is always responsive

71
Q

alpha motor neurons

A

activate extrafusal muscle fibres

72
Q

gamma motor neurons

A

activate intrafusal muslcle fibres

73
Q

reflex

A

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
Q

5 componenets of a reflex arc

A
receptor
afferent sensory signal 
integration center - processing of signal, integration with association neurons 
efferent motor neuron 
effector organ (skeletal muscle)
75
Q

reflexes can be ___ and ___

A

excitatory and inhibitory

76
Q

myostatic stretch reflex

A

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
Q

plyometrics

A

rapid stretches and stimulate the muscle spindels causing a reflexive muslce action to increases force production

78
Q

asynchronized activation of alpha and gamma

A

gamma first, can be coordinated

79
Q

golgi tendon organs

A

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
Q

inverse myostatic reflex

A

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
Q

untrained vs trained in plyometric training

A

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
Q

volitional control for

A
important for skilled movement 
function at the level of a single motor unit.
83
Q

myoelectric prosthetic

A

take sensors to mount them on signals for them to take it and relay - train ind units -

84
Q

volitional contraction of a muscle alters

A

muslce tension, length, and position ___

85
Q

muscular changes due to volitional contractions are sensed by

A

receptors and transmitted to the central nervous system through afferent neurons

86
Q

continual integration of this info and readjustments by the NS ensures

A

coordinated movement

87
Q

flexibility

A

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
Q

3 types of stretching

A

ballistic stretching
static stretching
proprioceptive neuromuscular facilitation

89
Q

ballistic stretching (3)

A

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
Q

static stretching

A

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
Q

proprioceptive neuromuscular facilitation

A

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
Q

why increase the agonist muscle when stretching

A

increase the ROM

93
Q

physiological responses to stretching (2)

A

improves ROM

before exercise may lead to performance deficits in strength, power, and reaction time

94
Q

flexibility training (2)

A

does not limit strength, power, and reaction times - may contribute to reduced DOMS after eccentric dynamic exercise

95
Q

does stretching and flexibility prevent injury?

A

no clear evidence

96
Q

why does stretching help with eccentric dynamic exercise

A

longer muscles

97
Q

take home msg for stretching

A

evidence on injury prevention, performance and health is not as strong as aerobic and RT - AT - RT - flexibility

98
Q

what are all the factors that can affect muscle tension

A
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