muscle fibre types Flashcards
what are the 3 muscle fibre types
type 1-slow oxidative-slow twitch
tye 2a-fast oxidative glycotic
type 2x-fast glyotic
slow twitch fibres
slow contraction speed
better adaptedd to low intensity exercise
prodcue their energery aerobically (presnce of o2)
type 2a fast oxidative glycotic fibres
more resitant to fatigue
used for events such as 1500m in athletcs
where longer burst of energy is needed
type 2x fast glycotic fibres
used for highly exploseive events e.g e.g 100m run where quick burst of energy are needed
characteristics of slow twitch fibres
slow contraction speed
high levels of
mitochondrial density
myglobin content
capillery density
chearcertsrics of type 2a fast oxidative glysoctic fibres
fast contractio speed
meddium mitochondrial denisty
myglobin content
and medium capillery density
characteristics of type 2x fast glycotic fibres
fast contraction speed
large motor neurone size
low levels of mitochondrial dnsity
myglobin content
adn low levels of capillery density
what are muscle fibres grouped into
motor units
motor unit-motor neurone and its muscle fibres
small muscle
used for fine motor control
e.g yes
lagre muscle
used for gross movements
e.g muscles for legs and quadriceps
all or none law
once motor neurone stimulates muscle fibres either all of them contract or none of them contract
what motor units will brain recurit for low intesnity exercisen
slow twitch
what are the two ways to increase strength of contraction
wave summation
spatial summation
wave summation
repeated nerve impulse with no time to relac so a smooth sustained contraction occurs (tetanic contraction))
spatial summation
when impulses are recieved at same time at diffrent places on enurone
recruitment of additional bigger motor units within a muscle to develop force
