Module 32 - Skeletal Muscle Physiology Flashcards
what is a motor unit
somatic motor neuron and all the muscle fibers that it serves
true or false: each fiber can have many different connections
false. each fiber has 1 connection
the smaller the muscle the ____ fibers/units
less
what is recruited first? stronger or weaker units?
weaker
what is asynchronous recruitment
alternately contracting motor units to allow muscle contraction for longer periods of time
what is submaximal stimulus
activates multiple recruited motor units to produce a greater force of contraction
how can u increase muscle contraction strength?
exercise to increase myofibrils
what is the isometric contraction
length of the muscle doesnt change but tension increase
what is isotonic contraction
tension produced is constant but length of muscle changes
what are the two types of isotonic contraction
concentric: muscle shortens when tension overcomes resistance (bicep curl towards up/up)
eccentric: muscle lengthens when resistance is greater than tension (bicep curl away from you/down)
what are the 3 fiber types
I, IIa and IIx
what is the largest fiber type
IIx
what fiber type has the most mitochondria? what does that say about its production of ATP
type I has the most mitochondria. it means that its highly oxidative, so it produces more ATP but its slower at that production.
what fiber type has the least blood supply?
type IIx
what does being fatigue resistant say about the contraction of the fiber? which type has the best fatigue resistance?
better fatigue resistance = fiber contracts for longer periods of time = muscle focuses on endurance and not force.
type I.
