Muscle physiology 2 Flashcards
what does muscle tension depend on
Number of muscle fibres contracting within the muscle
Tension developed by each contracting muscle fibre
in skeletal muscle which is shorter; duration of ap or resulting twitch
action potential
how to bring about a stronger contraction
repetitive fast stimulation of skeletal muscle
tetanus
if a muscle fibre is stimulated so quick it doesnt have time to relax between stimuli; sustained contraction
can cardiac muscle be tetanosed and why
no due to the long refractory period
when can max tetanic contraction be achieved
when a muscle fiber is at its optimal length
what is approx a muscles optimal lenght
its resting leength
what is isotonic contraction used for
body movements and moving objects
muscle tension remains constant as the length changes
what is isomeric contraction used for
supporting objects in fixed positions and maintaining body posture
when does muscle tension develop
constant muscle length
so when holding in position
what muscle fibres are more resistant to fatigue
those with greater capacity to synthesise ATP
metabolic pathway when o2 not present
glycolysis
metabolic source when o2 is present
oxidative phosphorylation
what are type 1 fibres used for
prolonged relatively low work aerobic activities e.g. maintenance of posture, walking
slow oxidative
type 2a fibres
fast oxidative
also known as intermediate-twitch fibres) use both aerobic and anaerobic metabolism and are useful in prolonged relatively moderate work activities e.g. jogging
