Shared Flashcard Set

Details

Exercise Physiology Exam 1
O2 Consumption/Fuel Selection
42
Other
Not Applicable
01/09/2005

Additional Other Flashcards

 


 

Cards

Term
VOCAB: Oxygen Deficit
Definition
The difference between the O2 actually used and the total O2 that would have been used if state state metabolism had been achieved immediately after start of exercise.
Term
VOCAB: Steady state
Definition
The point in exercise where you use O2 for energy production, which is more dependable for long-term use.
Term
What are you using for energy before you hit steady state?
Definition
Anaerobic energy systems.
Term
VOCAB: VO2
Definition
The rate of O2 uptake (L/min). NOT O2 consumption!! We have no idea how much O2 the body is actually consuming. only how much it's pulling in!
Term
VOCAB: Respiratory Quotient, AKA Respiratory Exchange Ratio
Definition
CO2 produced = O2 the body takes up. This can ONLY be calculated if the subject is in steady state of activity!
Term
What factors affect the rate of energy production?
Definition
Increased ADP, and increased ATP
Term
How does increased ADP affect the rate of energy production? By what mechanism?
Definition
Increased ADP stimulates rate-limiting enzyomes to increase energy production.
Term
How does increased ATP affect the rate of energy production? By what mechanism?
Definition
Increased ATP inhibits rate-limiting enzymes which decreases energy production.
Term
How does training impact O2 deficit? Is this beneficial? Why or why not?
Definition
Training decreases O2 deficit, which is beneficial because it promotes conservation of carbohydrates by decreasing the time needed to get to the aerobic phase of exercise. It increases flow to muscles, increases aerobic enzymes, and increases cardiac output.
Term
VOCAB: Excess Post-exercise O2 Consumption
Definition
Oxygen debt that occurs after the conclusion of exercise, during the recover phase.
Term
Why do we experience EPOC? (6major reasons)
Definition
1. Because we need to re-synthesize phosphocreatine. 2. Need to restore blood O2. 3. HR and RR continue to be elevated, and those muscles work above baseline level so they require increased O2. 4. Muscle use --> incr. heat, which --> BMR --> incr. enzyme speeds --> incr O2 use. 5. Hormones (epinephrine, etc) released during exercise also increase BMR, which Incr. O2 Consumption. 6. May have increased lacate which requires O2 to be transported.
Term
What factors influence fuel selection?
Definition
1. Diet - you can force use of one fuel over another through food intake. 2. Intensity of exercise. 3. Duration of exercise.
Term
What are the crossover points for the different energy systems? (times at which one system takes over for another)
Definition
1-5sec of exercise = phosphagen (anaerobic)
>5sec of exercise = phosphagen and glycolytic. (also anaerobic) >45sec = phosphagenic+glycolytic+oxidative (mostly aerobic)
Term
What happens to EPOC if activity level is increased?
Definition
EPOC increases.
Term
Where is glycogen stored?
Definition
In the muscles and liver.
Term
VOCAB: Cori Cycle
Definition
Process in the liver which produces glucose.
Term
What fuel source do we preferentially use of high intensity/short duration activities?
Definition
Carbs
Term
What fuel source do we preferentially use for low intensity/long duration activities?
Definition
glycogen
Term
What do we use for energy in the inital phase of activity?
Definition
phosphagen system and carbs
Term
As you increase activity, what happens to muscle use of glucose?
Definition
As you incr activity, the muscles use more glucose.
Term
Which of the following does the body use most during mild intensity exercise? Plasma FFAs, muscle glycogen, plasma glucose or muscle triglyceride?
Definition
plasma FFAs
Term
Which of the following does the body use most during moderate intensity exercise? FFAs, muscle glycogen, plasma glucose or muscle triglyceride?
Definition
It uses them all fairly equally.
Term
Which of the following does the body use most during high intensity exercise? FFAs, muscle glycogen, plasma glucose or muscle triglyceride?
Definition
muscle glycogen. Not much fat is used.
Term
With increased intensity, what fuel source do you use more of?
Definition
glucose
Term
With increased duration what fuel source do you use most?
Definition
Plasma FFAs
Term
VOCAB: Cross Over Point
Definition
The point in exercise intensity where you start to use more cabs than lipids. (approx 40% VO2 max)
Term
At 65-75% of VO2max, there is an ideal split of carbs and lipids. If you continue to exercise at that level for a longer duration, and you have adequate supply of all substrates, what is the relationship between carb and lipid use, and how does this compa
Definition
As long as the intensity is kept the same, the proportion of carb to lipid use will be maintained for the duration of the activity. Muscle stores will be used less as the duration of the activity continues. Carb and lipid use will increase proportionally as intramuscular store use decreases.
Term
VOCAB: Fatigue
Definition
When exercise proceeds past the point that comprimises liver and muscle glycogen supply, despite sufficient O2
Term
If you eat a meal filled mostly with carbs, will you have more or less endurance than if you had eating a meal filled mostly with protein?
Definition
more, More, MORE! :)
Term
What measurement tells us if we're using primarily carbs or lipids for energy?
Definition
RER - Respiratory Exchange Ratio. VCO2/VO2
Term
If you're using purely carbs as an energy source, the RER will = ?
Definition
Uno.
Term
If you're using purely fat as an energy source, your RER will =?
Definition
0.7
Term
In order to measure RER, the subject must meet certain criteria. What are those criteria? (3)
Definition
Must be in steady state, must not increase intensity, and they must be over the O2 deficit level.
Term
What type of relationship do work load and VO2 have?
Definition
linear. As Work load increases, VO2 increases linearly.
Term
VOCAB: VO2 Max
Definition
Plateau in O2 uptake even when there's increasing workload. IF YOU DON'T SEE A PLATEAU IN THE GRAPH, YOU CAN'T SAY YOU GOT TO VO2 MAX! (I guarantee she'll try to trip us up with that one.)
Term
VOCAB: VO2 Peak
Definition
The highest point on a VO2 over workload graph, if you don't see a plateau.
Term
What determines VO2 Max? (4)
Definition
gender, age, heredity, a little bit by fitness.
Term
Can you change your VO2 max?
Definition
not for the most part. It's pretty much pre-determined.
Term
VOCAB: MET (metabolic equivalent)
Definition
Rate of energy expenditure at rest.
Term
A Calorie is a measure of what?
Definition
heat. Amt of energy required to raise 1g of H20 by 1 degree C.
Term
VOCAB: Direct Calorimetry
Definition
subersion of an individual in H2O to measure the temperature change.
Term
Indirect calorimetery, equation
Definition
Food + O2 intake --> Heat + CO2 + H2O
Amt of O2 consumed is directly related to heat.
Supporting users have an ad free experience!