ch 6 fatiuge muscle soreness and muscle cramps

Question 1

definition of fatigue

Answer 1

decrement in muscular performance with continued effort coupled with general sensations of tiredness

inability to maintain required power output to continue muscular work at a given intensity

Question 2

2 major divisions of the causes of fatigue

Answer 2

central and peripheral

Question 3

what is central fatigue

Answer 3

alterations in neural control of muscle contraction

Question 4

what are the 3 causes of peripheral fatigue

Answer 4

decreased rate of energy delivery

accumulation of metabolic byproducts

failure of muscle fibers contractile mechanisms

Question 5

what 2 things can deplete that cause peripheral fatigue

Answer 5

PCr and glycogen

Question 6

as you do more maximal repeated contractions what happens to PCr levels

Answer 6

they decrease

Question 7

muscle glycogen is the predominant fuel for activities _____ 10/15 seconds (not counting aerobic)

Answer 7

greater than

Question 8

rate of glycogen depletion during exercise, is faster _____ during the duration of exercise

Answer 8

earlier on

Question 9

glycogen depletion correlates strongly with what

Answer 9

fatigue

Question 10

depletion of muscle glycogen interferes with what

Answer 10

excitation-contraction coupling and Calcium release from the sarcoplasmic reticulum

Question 11

how does ATP generation and glycogen correlate

Answer 11

low glycogen, slow atp generation

Question 12

the first fibers recruited during exercise are also the first to be ____ of glycogen

Answer 12

depleted

Question 13

different types of activities will deplete ______ muscle groups at ______ rates

Answer 13

different, varying

Question 14

the feeling of glycogen depletion is usually

Answer 14

mental, however actual glycogen depletion is linked with fatigue

Question 15

what are the 3 metabolic by-products most associated with fatigue

Answer 15

inorganic phosphate, lactic acid (lies) , and H+

Question 16

inorganic phosphate _____ during what kind of exercise as PCr and ATP is broken down?

Answer 16

increases, during short and intense exercise

Question 17

what does high concentrations of inorganic phosphate do that contributes to fatigue?

Answer 17

impairs contractile function of myofibrils

reduces Calcium release from sarcoplasmic reticulm

inhibits ATP breakdown (due to negative feedback loop)

Question 18

lactic acid is produced where?

Answer 18

cytoplasm

Question 19

lactic acid only accumulates during what kind of effort

Answer 19

breif, highly intense effort

Question 20

what does lactic acid do after being produced

Answer 20

can be taken up and used by that muscle fiber or shuttled to other sites

Question 21

is lactic acid to blame for fatigue

Answer 21

no, H+ is the trifiling cunt that is released via lactic acid dissociation

Question 22

what does the accumulation of H+ cause

Answer 22

acidosis, too low of pH

Question 23

what pH limits phosphofructokinase activity

Answer 23

pH of <6.9

Question 24

what pH does glycogen breakdown begin to halt

Answer 24

pH of <6.4

Question 25

aside from acidosis what does accumulation of H+ cause in muscle

Answer 25

lowers amount of calcium released from sarcoplasmic reticulm

Question 26

how long does the decreased pH from excess H+ normally last

Answer 26

35min maximum

Question 27

neuromuscular fatigue causes

Answer 27

-reduced release of acetylcholine -hyperactivation of cholinesterase (which causes low acetylcholine levels and cant cause action potential) -inhibition of cholinesterase ( acetylcholine buildup and cant relax muscle) -membrane develops higher threshold for stimulation -competition with acetylcholine with other substances at receptors -potassium leaves intracellular space (decreased membrane potential) -calcium retained in sarcoplasmic reticulum (due to low glycogen availability and metabolic by products)

Question 28

what is the central governor theory

Answer 28

processes occur in the brain that regulate power output by muscles to maintain homeostasis and prevent unsafe levels of exertion

Question 29

central governor theory states that we limit exercise by

Answer 29

decreasing the recruitment of muscle fibers and therefore feel fatigued

Question 30

most individuals terminate exercise before______________

Answer 30

physiological exhaustion

Question 31

summary of central governor theory

Answer 31

your brain tells you to be a pussy, you are not going to carry the boats or the logs

Question 32

what does the psychobiological model of fatigue state

Answer 32

ultimate determinant of endurance performance in highly motivated athletes is interaction between perception of effort and motivation basically the central governor theory but voluntary cognition

Question 33

does "mental fatigue effect performance

Answer 33

no, it will however effect RPE

Question 34

exercise in the heat does what to CHO utilization

Answer 34

increases, may be caused by increase epinephrine secretion

Question 35

it is theorized that high muscle temperatures impair both________ and __________-

Answer 35

skeletal muscle function and muscle metabolism

Question 36

what is the sensation of acute muscle soreness

Answer 36

pain felt immediately after exercise stiffness, aching, and tenderness

Question 37

what can cause acute muscle soreness

Answer 37

accumulation of end products (H+) tissue edema (swelling)

Question 38

how long does it take for acute muscle soreness to go away

Answer 38

a few hours (very fucking scientific, this is from the slides)

Question 39

what is delayed onset muscle soreness physiologically

Answer 39

tissue damage inflammatory response (needed for recovery)

Question 40

what training is thought to be primary initiator of delayed onset muscle soreness

Answer 40

eccentric

Question 41

2 primary theory's of muscle cramps

Answer 41

electrolyte depletion theory neuromuscular control theory

Question 42

what is the electrolyte depletion theory of cramping

Answer 42

sweating from Ex leads to electroyte imbalences which lead to hyper excitable nerve terminals

Question 43

what is the neuromuscular control theory of muscle cramping

Answer 43

exercise associated muscle cramps occur when some aspect of control between motor neuron and muscle becomes altered