neuromuscular system Flashcards
what are the three muscle fibre types
slow twitch fibre (type 1)
fast twitch glycolytic (type 11b)
fast oxidative glycolytic (type 11a)
what do the slow twitch fibres do
slow speed contraction
use of oxygen to to produce energy
high resistance to fatigue
name a sporting example that would use slow twitch fibres
long distance runners
triathletes
what do the fast twitch glycolytic fibres do
greatest anaerobic capacity lowest resistance to fatigue high force of contraction fastest contraction speed anaerobically produces energy
name a sporting example that would use fast twitch glycolytic fibres
100m sprint
sprint to get a pass in hockey
what do the fast oxidative glycolytic do
fatigue quickly
high glycolytic capacity
more resistance to fatigue than type 11b
higher force of contraction than slow twitch
faster contraction speed than slow twitch
name a sporting example that would use fast oxidative glycolytic fibres
800m runner
1500m runner
name 3 structural characteristics for slow twitch fibres
high mitochondria density
high triglyceride stores
high capillary density
name 3 structural characteristics for fast oxidative glycolytic fibres
moderate capillary density
medium pc stores
medium mitocondrial density
name 3 structural characteristics for fast twitch glycolytic fibres
low mitochondrial density
high PC stores
low capillary density§
what is a motor unit
a motor nurone and its muscle fibres
only one type of muscle fibre can be found in one motor unit
each muscle is made up of many muscle units which vary in size
what is a motor neurone
nerve cells which transmit the brains instructions as electrical impulses to the muscle fibre.
each motor neurone has branches that that end in the neuromuscular junction on the muscle fibre
what is the neuromuscular junction
where the motor neurone and the muscle fibre meet
what is the all or none law
a sequence of impulses must be sufficient intensity to stimulate all of the muscle fibres in a motor unit to contract.
if the stimulus is not sufficient intensity then none will contract
it is not possible for a motor unit to contract
what is the threshold
the minimum amount of stimulation required to start a contraction
what is a muscle contraction
stimuli cause nerve impulses to be sent to the muscle which releases calcium, this must be present for the muscles to be contract
what is wave summation
this is when nerve impulses are repeated with no time for the muscle to relax causing a build up of calcium
this produces a more forceful and sustained contraction known as a tetanic contraction
what is a tetanic contraction
this produces a forceful sustained and smooth contraction
what is spatial summation
this is when two or more impulses are received by the neurone at the same time at different places
recruits additional and bigger motor units within a muscle to develop more force
rotates the frequency of impulses to reduce fatigue and increase force of contraction
what is PNF
advanced stretch technique
one of the most effective forms of flexability training for increasing the range of motion at a joint
what technique does PNF use
CRAC technique Contract Relax Antagonise Contract
what contraction does PNF use
isometric
what is autogenic inhibition
a sudden relaxation of the muscle in response to to high tension
where are the Golgi tendon organs found
found between muscle fibre and tendon
