Exercise Physiology II (19) Flashcards
What are the 4 anaerobic supplies of ATP?
1- “stored” ATP
2- Myokinase reaction (ADP + ADP)
3- Creatine phosphate
4- Glycolysis
What are the aerobic supplies of ATP?
CHO, Fatty Acid and Amino Acid oxidation
Which is quicker to turn on…aerobic or anaerobic ATP generating pathways?
Anaerobic
What is O2 deficit?
ATP is provided by anaerobic mechanisms until aerobic mechanisms can turn on
What is O2 debt?
Continuing aerobic mechanisms even after ATP demand has stopped in order to replace ATP, Creatine Phosphate and O2 stores
What is the anaerobic threshold?
When anaerobic processes supplement ATP production.
Is the anaerobic threshold the same for every individual?
No..it varies between people and it can be increased with training
What is the relationship between RER and exercise intensity?
RER increases with higher intensity workout
Do you oxidize more FAs or CHOs in higher intesity exercise?
More CHO and less FAs
What does RER during exercise depend on?
1- Exercise intensity
2- Prior dietary history
3- Exercise duration
4- Fitness level
Does exercise fatigue come quicker on a high fat diet or a high carb diet?
High fat diet
What is the cause of increased glucose uptake by skeletal muscle during exercise?
Enhanced insulin sensitivity
When is glycogen depletion most severe?
When exercise is performed at about 75% VO2 max.
What is the cause of fatigue at most % of VO2 max?
Causes aside from glycogen depletion.
Describe the differences in FA mobilization and utilization between trained and untrained muscle?
Trained muscle takes up and oxidizes more free fatty acids and mobilizes more free fatty acids
Describe the difference in lactic acid levels in trained vs untrained muscle when exercising?
Untrained muscle has increased levels of lactic acid
Why are increaed levels of lactic acid bad?
Because lactic acid inhibits lipolysis, so free fatty acid release is inhibited resulting in a decrease in free fatty acid mobilization and decrease in free fatty acid uptake.
What happens to VO2 max during extended periods of inactivity?
Decreases
When beginning to exercise after a period of inactivity, who recovers their VO2 max faster…an individual who is trained or untrained?
An untrained individual recovers quicker and is also able to exceed their original VO2 max
What is VO2 max a product of?
Max CO and Max (A-V) O2 difference
Why does (A-V) O2 difference increase with increased VO2?
Because an increased capillary density which increases surface area and decrease distance of diffusion
Also, aerobic training stimulates mitochondrial synthesis
Why does CO increase with increased VO2?
CO= HR x SV
SV increases in individuals who train. Heart rate does not reach that much.
Why does SV increase with increased VO2 max?
Due to a healthy increase in left ventricle volume. Additionally the heart is a muscle and with training it is able to get stronger.
Describe the SV and HR of a well trained athlete when compared to a untrained individual when exercising?
SV is increased and HR is decreased
What is RPP?
Rate pressure product
RPP= HR x SBP
Describe the RPP of a fit person verses an unfit person for any given work rate?
RPP is lower at any given work rate in fit vs unfit
What are the consequences of a lower RPP?
Heart requires less oxygen
Heart requires decreased blood flow
Heart operates more efficiently
What is the Borg scale?
A scale designed so that the number of reported (percieved level of exertion) multiplied by 10 wuould approximate the HR at that exercise level
What happens to endurance even as VO2 max plateaus?
It continues to increase due to muscle adaptations….increased mitochondria that are more efficient and larger
What are the qualities of an ideal exercise regimen?
Dynamic activity using large muscle groups
3-5 times a week
20-60 min
Intensity of 55%- 75% VO2 max
What is the overload principle?
Body systems must be exposed to sufficient stress to improve and as training adaptations occur, stress must be increased.
