Muscle fatigue Flashcards
what is muscle fatigue
muscles can no longer perform properly
what happens during muslce fatigue
there is a decrease in tension despire continued stimulation and
rest and relaxation
what are the 5 reasons muscle fatigue occurs due to
elevated extracellular k+concentration
depletion of metabolic reserves/insufficient oxygen
low pH
damage to sarcolemma and SR
muscle exhaustion and pain
where is there elevated extracellular k conc
in t tubule
it hyperpolarizes the cell to be less excitable
what does the depletion of metabolic reserves limited because of
it is limited to glycolysis
why is low pH bad
a decrease in intercell pH alters enzyme fxn and a decrease in blood pH leads to feelings of weariness and a decrease in motivation to contract muscle, but an increase in pain
what is the sarcolemma again
cell membrain
what are pain receptors stimulated by
low pH (high H+ and lactic acid
what is a recovery period
time required after exertion for muscle to return to normal
what is the steps/ tasks that need to be health with during recovery related to lactic acid
it leaves muslce cells and travels to the liver where it is converted to pyruvic acid. that i s then used to form glucose which is stored as glycogen at the liver or delivered to other cells
what happens at the end of recovery
o2 becoems available
mitochondrial activity resumes
energy reserves accumulate
what is oxygen debt refering to
after exercise, the body needs more oxygen than usual to normalize metabolic activities
what does an increased metabolic rate lead to
increased energy needed , whcih also leads to increased body temp and increased sweat glad activity…
needs to increase liver fxn and energy reserve in muscle
what is short term muslce soreness due to
low pH
what is muslce soreness following excercise entail
starts a few hours after excersise
can continue for several days
muscle tender to the touch
decreased range of motion
swelling
muscle fatigue
decreased muscle strength
what are the possible causes of muscle soreness
damage to muslce cell membrane
due to muscle spasms/contractures (myosin binds but doesn’t release) (fatigue)
damage to tendons
muscle metabolism is altered by what
level of activitiy
during low intensity exercise, what oxygen is available. what respiration provides the energy… how long
there is adequate oxygen
aerobic respiration
long time
during high intensity exercise, what oxygen is available. what respiration provides energy… how long
not adequate oxygen
anaerobic respiration
short time
what are the 2 factors of muslce performance
power and endurance
how are power and enduracne related
inversely
power def
max amount of tension produced
endurance def
amount of time an activity can be sustained
what is performance dependent on
fiber type
fast fibers are what (power n endurance wise)
powerful fibers, low endurance
slow fibers are what (power n endurance wise)
less powerful, high endurance
intermediate fibers are what (power n endurance wise)
medium power and medium endurance
do fast fibers contract slow or fast
fast, within .01 sec
are fast fibers large or small diameter
large
do fast fibers hvae a large or small glycogen reserve
large (glycolysis for atp)
do fast fibers have a lot or a few mitochondria
few
do fast fibers have strong or weak contractions
strong
so fast fibres fatigue quickly or slowly
quickly
are fast fibers white or red fibers
white, they lack myogloglobin
are slow fibers fast or slow at contracting
slow
.03 sec
are slow fibers large or small diameter
small
are slow fibers with more or a few mitochondria
more (aerobic repiration primarily
do slow fibers have a high or low o2 supply
high, increase of capillaries
does slow fibers have myoglobin
yes, a pigment that binds o2
do slow fibers have prolonged or short lived contractions
prolonged
are slow fibers white or red fibers
red, they do have myoglobin
what fibers are more so posture muscles, ones used to stand around or just walk around
slow fibers
