Exam 2 Flashcards
one advantage of using immediate energy sources?
able to get energy quickly (highest rate of energy transfer). 6-8x as fast as an aerobic pathway
one disadvantage of using immediate energy sources?
amount of storage is finite
after stored muscle glycogen and CP system is used, what is used to make ATP
glycogen (stored in the muscle). glycolysis…turning glycogen into ATP
during activities less than ____%of VO2 max lactate accumulation=lactate disappearance because lactate is being converted to pyruvate bc there is oxygen present
50%
between which time interval is lactate accumulation the highest in high intensity activities
60-180 sec (1-3 min)….during glycolysis
how long can we do exercises using stored reserves (Stored ATP and CP system)?
1 minute max
after 50% VO2 max, which pathway is mostly being used?
Anaerobic
describe tissue hypoxia and how it causes problems in the body
it is when the glycolytic mechanism predominates and we get too much NADH produced for the oxygen available. not enough oxygen available to accept the hydrogen being produced, so lactic acid forms.
___% of Lactic acid is used to create energy elsewhere (heart, other muscles, liver, etc)
70%
__% of Lactic acid is converted to glucose
20%
__% of Lactic acid gets converted to amino acids
10%
which type of muscle fiber has the most LDH
2b (fast glycolytic)
what does LDH do?
if converts lactic acid to pyruvic acid (removes the hydrogen to lactic acid)
what is the blood-lactate threshold
when lactate levels in the blood start to accumulate
how does the blood-lactate threshold increase through training? (3 things)
- ) training adaptations occur….endurance training increases the number of capillaries in the body, size of mitochondria, etc.
- ) Faster removal of lactate….neighboring cells respond to constant levels of high lactate levels during training by increasing their metabolites to remove the lactic acid
- ) some people may have a genetic endowment to have increased blood flow to the muscle or a greater number of mitochondria in the muscle)
do endurance or power athletes experience a 20-30% incr in the amount of lactic acid they can produce
power athletes
why do training people have the capacity to produce higher levels of lactic acid (3 things)
- ) improved motivation
- ) increased intramuscular glycogen stores…more glycogen in the muscle glycogen means larger muscle size
- ) increase in glycolytic enzymes
have to switch to aerobic pathway after how long maximum?
3 minutes max
why can’t steady state actually go on forever?
- ) because we would eventually deplete our energy supply (carbs, fats, proteins) needed for the energy production pathways
- ) loss of hydration…exercise duration shorter in hot climates
- ) the amount of stored glycogen is a limiting factor…muscle glycogen is the only type of glycogen that powers exercise
balance between energy production and energy demand=
steady state
why doesn’t steady state occur immediately?
anaerobic pathways are doing the work before going to steady state. (think: takes time for body to get oxygen into the cells, so have to rely on other ways to produce energy)
why does the shift to aerobic pathways occur
**the consumption of oxygen is proportional to the need for atp….production makes demand
do endurance athletes, power athletes, or both types reach a steady state faster (have less of an oxygen deficit)
endurance only!! endurance training allows one to almost go directly into the aerobic pathways
why do endurance athletes reach steady state faster (have less of an oxygen deficit)?——-3 things
- ) more rapid increase in bioenergetics…this means they have more enzymes that shift them toward aerobic cycle and away from lactate production
- ) increase in overall cardiac output….increase in blood flow means greater exchange happening at the lungs so oxygen can get into and around the body quicker
- ) get better at shunting the blood to the active tissues (tissue perfusion)
maximal aerobic power is the same thing as____
vo2 max
maximal oxygen consumption is____
vo2 max
what does vo2 max quantify?
person’s ability to produce energy via the aerobic pathway
does vo2 max incr or decr w/ age?
decr
do young men or young women have a higher vo2 max?
young men
do older women or older men have a higher vo2 max
older women (vo2 max become more similar as we age…between genders)
what are some physiological changes that contribute to an incr in vo2 max?
(6 things)
- ) Incr pulmonary ventilation
- ) incr hemoglobin concentration
- ) incr blood volume
- ) affecting cardiac output (stronger heart)
- ) changes in peripheral blood flow
- ) incr in aerobic enzyme concentration
low myoglobin content in found in______fibers which is _______muscle
fast glycolytic (2b), white
red muscle means what?
high myoglobin content (and oxidative)
stop and go sports would use what muscle fiber type a lot?
type 2a (maintain both types of fibers for most sports)
rate of recovery for light aerobic exercise?
rapid recovery because there was a rapid attainment of steady state, so not much oxygen deficit and not much lactic acid being produced….fast component is the only thing seen here
rate of recovery for moderate to heavy exercise?
both fast and slow component seen bc lactic acid does accumulate. longer recovery time because it took a bit longer to reach steady state
rate of recovery for maximal exercise?
no steady state is ever produced, there is lots of lactic acid accumulation so a large slow component to remove the LA from the body
recovery time is dependent on both intensity and duration but MAINLY
Intensity
what are some other factors aside from intensity that influence recovery time?——5 things
- ) Body temperature….the more we heat up during exercise, the longer it takes to recover.
- ) Reloading lungs….have to get air back into the lungs in the same proportion as before exercise
- ) Reloading myoglobin
- ) Elevated Heart Rate…heart needs to have energy consumption to make it beat
- ) Tissue repair…need oxygen to repair damaged tissues
active recovery good for??
non-steady state things (done to remove the lactic acid)
passive recovery good for??
steady state—bc we want a process that will resynthesize phosphate and replenish oxygen in the body. so doing nothing is ideal to allow oxygen to be replenished in the body
what is Dalton’s law?
percent contribution of gas in a mixture makes up the total pressure
how does Dalton’s law relate to gas exchange at the lungs?
this shows that not all gases will be able to reach the lungs equally/not all gases have the same effect
describe H20, N2, and O2 levels of air in the trachea compared to the atmosphere
H20….incr
N2….decr
O2….decr
hydration of the air occurs____
in the trachea
describe H20, O2, and CO2 levels in alveoli compared to trachea
H20…constant
O2….decr again
CO2….gained LOTS
how does the composition of the air in the alveoli stay constant
functional residual capacity (air that always stays in the lungs)
Henry Law says what
the amount of gas dissolved in solution varies depending on the pressure
what two things affect movement of gases into and out of the lungs?
pressure differential and solubility of the gas
net movement of gas goes from…
high to low pressure
which is more soluble co2 or o2
co2 (25x more soluble)
which is at a higher pressure co2 or o2 (thus wants to move to a lower pressure0
o2
why is partial pressure of oxygen in the blood lower than that of the alveoli (lungs)?
venous admixture
factors that impair gas transfer? (2 things)
- ) thickened alveolar membrane (particulate matter)
2. ) reduction of surface area of alveoli (emphysema caused by smoking)
why do we always maintain co2 levels in the blood?
ventilation is controlled by co2 levels, so co2 tells us how hard we need to breathe. if co2 levels are high the pons/medulla oblongata are activated to stimulate the respiratory center
how many HEMES total in hemoglobin
4
endurance athletes can suffer from what type of anemia?
Iron deficiency
why does endurance training cause one to suffer from fe deficiency anemia?
long distance training reduces fe content so they have to make sure they consume lots of iron in their diet
what is cooperative binding?
the binding of one oxygen to hemoglobin promotes binding of more and more hemoglobin. hemoglobin wants to be fully saturated with 4 oxygen total
hemoglobin will not give up oxygen until the partial pressure of oxygen gets below what %?
60%
what is the Bohr effect?
an increase in plasma acidity (or an increase in body temperature) that causes hemoglobin to give up oxygen to the tissue more easily (this shifts the curve down and to the right). note: the change in pH is caused by the accumulation of lactic acid
hemoglobin doesn’t give off more than ____% of what it has
70%
why does hemoglobin stay 70% saturated even after offloading oxygen at tissues
because it needs to have a reserve….just in case
what are the 2 methods to change the amount of perfusion happening?
- ) change the amount of blood to certain place that need it (shunting)
- ) hemoglobin more likely to give up oxygen to active than inactive tissues
why is hemoglobin more likely to give up oxygen to active over inactive tissues?
active tissue is using up its oxygen, so the gradient is greater.