mr smith-neuromuscular system Flashcards
sympathetic system
prepares body for exercise
referred to as fight or flight reponse
parasympathetic nervous system
relaxes body
slows down functions
rest and relax
what are the three types of mle fibres
slow oxidative type 1
fast oxidative glycolytic type 11a
fast glycotic type 11x
sally fed flynn
characteristics of slow twitch fibres type 1
slow contraction speed
adapted for lower intensity exercises
e.g. long distance running
produce their energy aerobically (with oxygen)
charcteristics of fast oxidative glycotic (type II
faster contraction speed
can generate greater force of contraction
fatigue very quickly
used for short, intense burts
e.g sprint
use their energy anaerobically (without presence of oxygen)
what are the two types of fast twitch fibres
fast oxidative glycotic-type 11a
fast glycotic-type 11x
type IIa fast twitch fibre
called oxidative glycotic
more resistant to fatigue
used for events with longer bursts of energy needed
e.g. long distance 1500m run
type 11x of fast twitch fibre
fast glycotic
fatigue much quicker then type 11a
used for highly explosive events
e.g 100m sprint
quick, short burst of energy needed
charctersitcis of all 3
mitchondria density
capillery density
myoglobin
all go high, medium low
what can happen to a muscle fibre through training
can increase in size
what is hypertrophy
where the muscle becomes bigger and stronger
what are muscle fibres grouped into
muscle units
what does a muscle unit consist of
muscle neurone and muscle fibres
what size motor units do msucles have
fine, controlled movements-have motor units with little amount of fibres e.g msucle moevemtn of eye
what type of motor units will body recruit
for lower intensity exercises, brain will recruit slow twitch motor units
for higher intensity exercises, brain will recruit fast twitch muscle units
all or none law
once the motor neurone stimulates muscle fibres. either all contract or none at a
what are the two ways to increase the strength of a contraction
wave summation
spatial summation
wave summation
where there is a repeated nerve impulse with no time to relax so smooth and doesn’t have twitches
PNF
-type of advanced stretching technique
-increases range of movement and flexibility
-most practical is CRAC technique contract relax antognist contract
2 types of proprioceptors
golgi tendon organs
muscle spindles
muscle spindles
often called stretch receptors
provide info to CNS about how far and fast muscle fibre should be stretched
CNS sends signal back to muscle telling it to contract
triggers stretch reflex
this reflex action causes musle to contract to prevent overstretching
reduce risk of injury
golgi tendon organs
detect levels of tension
msucle contracted isometrically
known as autogenic inhibition
what is autogenic inhibition
sudden relax of muscle in rerpsonse to high tension
steps of PNF
perfomer perfromers passive stretch
with help of partner to lift up their leg
stretched detected by muscle spindels
muscle is stretched too far, stretch reflex should occur
-individual then isometrically contracts leg by pushing against partners hand
-partner should hold enough resistance to keep them in stationery postion
-during isometric contraction, golgi tendon organs are activated
-inhibartory signals they send override the excitary signals from muscle spindles
-delay stretch reflex
what are two ways to increase the strength of contraction
spatial summation
wave summation
spatial summation
when the strength of a muscle contraction is increased due to recruitment of additional larger, stronger muscle motor units
wave summation
calcium is needed for a muscle to contact
if there are repeated nerve impulse with no time to relax, calcium is built up in the muscle cell creating a stronger forceful contraction
this contraction is called a tetanic contraction
PNF-propriorepector msuclular faciliation
advanced stretching technique
increases ranges of movement
most practical CRAC technique
contract, relax, antagonist, contract
what are the two types of prioproreceptors
msucle spindles and golgi tendon organs
msucle fibres
send info about hwo far and fast a muscle is beijg stretched
CNS send signal back telling it to contract, triggers stretch reflex which prevents overstretching
golgi tendon organs
detect changes in tension in muscle
muscle contracts isometrically, sense increase in tension and send signals to brain for antagonistic msucle to relax
known as autogenic inhibition
what are the stages of PNF
person perfomers passive stretch with help of partner
-extends leg until tension is felt
-detected by msucle spindles
-if msucle stretched too far, then stretch reflex will occur
-individual isometrically contracts muscle by pushing against partner for 10 seconds
-golgi tendon organ si activated
-inhibatory signals overide exciratory signals from msucle spindles
dalaing stretch reflex
-
isometric contraction
where there is tension in a muscle but no visiable movement
charcteristics
slow twitch have highest amount of
