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)