Energy Transfer part 2 Flashcards
What are the 3 energy systems that act as a continuum?
Short term(ATP-PCr) long term (Aerobic Glycolysis) intermediate (Anaerobic Glycolysis)
How is energy provided in the short term energy system?
from high E phosphates from ATP and CP
ATP and CP are stored in
contractile mechanisms of muscle (myofibril)
Short term energy system allows for
all out work for 10 seconds (anaerobic)
High power/ low capacity
How is short term energy altered?
with training. increase mass = increased storage capacity
Energy system for work lasting 30-180 seconds?/
anaerobic glycolysis
The lactic acid system (anaerobic glycolysis) provides energy for
muscle endurance and high intensity work/
What happens in anaerobic glycolysis?
glucose broken down. LA is end product causing burn due to decrease in pH of muscle.
in anaerobic glycolysis, where does the E to phosphorylate ADP come from?
blood glucose and stored glycogen.
Why can’t the body function on the lactic acid system for long?
enzymes and contractile mechanisms of muscle do not function with increased acidity.
Where does anaerobic glycolysis occur and whats sequence?
cytoplasm
Glycogen->glucose->LA= 2 ATP
sequence for aerobic system? when is it used?
Glycogen->glucose->pyruvate->Acetyl-CoA->Krebs cycle->ETS-H20 and CO2= 36 ATP
exercise over 3 mins
What must be present for the Krebs cycle?
O2
Steady state reflects balance between
E required and ATP production via aerobic metabolism.
What are the stages of fuel utilization?
1) Digestion/absorbtion
2) Degrading of subunits into acetyl CoA
3) Oxidation of Acetyl CoA -> CO2 and H2O with ATP production
Where does degrading stage occur?
Oxidation stage?
cytosol
Mitochondria
What are the subunits broken down in fuel utilization?
aa, glucose, FFA , glycerol units.
What are the 3 substrates?
Carbs
Fats
Protein
What substrates primary function is to supply E for cellular work?
what can It’s stored energy be used to generate?
Carbs
ATP anaerobically
What is required so that fat can be processed through the metabolic mill?
a continual breakdown of Carbs
What will glucose be broken down into?
what happens if there is O2 present? and if not?
Pyruvic Acid
Converted to Acetyl CoA and enters Krebs Cycle
LA forms
Rate of energy released in glycolysis is ____ than rate of E released from lipid breakdown.
3x faster.
How much fat is stored compared to carbs?
60-100,000 KCals in adipose tissue Vs. 2000KCals of Carbs
What is the storage form of Fat?
and what are they broken down into?
triglycerides.
glycerol and 3 Free Fatty Acids
Where are FFAs delivered to?
what happens if they are not used?
active tissues where they are mobilized.
converted to LDL by the liver.
How is mobilization of FFA from adipose tissue augmented?
E and NE, glucagon, and growth hormone.
How much ATP does the breakdown of FFA through beta oxidation and Krebs cycle yield?
441
Breakdown of glycerol through glycolysis and Krebs cycle yields
19 ATP
What is the largest endocrine organ in the body?
Fat.
What is secreted to decrease appetite
Leptin and Estrogens
Can serve important role as E substrate during sustained exercise
Protein.
How does protein provide energy?
amino acids converted to form then enter metabolic pathways.
In proteins, what must be removed and where does it occur?
nitrogen
deamination accuse in the liver.
Where does transamination occur?
skeletal muscle.
What happens to the nitrogen containing amino group?
must be excreted from the body dissolved in fluids.
Protein RDA for adults
athletes?
.83 g/kg of body mass
1.2-1.8 g/ kg of body mass.
What provides the means by which organic compounds formed from the breakdown of fats and proteins are metabolized for energy?
Krebs cycle.
Krebs cycle is the vital link between
Food E and chemical energy of ATP
Breakdown of FFA depends on
continual background level of glucose catabolism and O2
Degradation of FFA via the Krebs cycle continues only if
sufficient oxaloacetic acid is available to combine with Acetyl CoA formed during beta oxidation.
What cannot enter Krebs cycle during CHO depletion or restriction?
what results?
Acetyl CoA from beta oxidation and FFA from adipose tissue.
increase in the extracellular fluids and are converted to ketone bodies by the liver.
What does fuel utilization during exercise depend on?
intensity
Duration
Fitness
and Nutritional level.
What is prime contributor of energy during first few minutes of exercise?
why?
stored muscle Glycogen
because of ability to generate E without O2 presence.
What can 2 hour bout of exercise do?
deplete glycogen in the liver and exercising muscle.
What becomes source of energy as glycogen stores decrease during exercise progression?
blood borne glucose becomes major source of CHO and utilization of fat occurs
at about 2 hours of exercise, how much VO2 max is sustained and why?
50 %
slow rate of aerobic E release from fat metabolism.
Why are FFA released from adipose tissue?
due to hormonal stimulation of SNS and decreased insulin levels.
When does protein breakdown occur?
when CHO stores are low.
Fuel source during <30% VO2 max? 40-60? 75? >80?
<30=muscle fat
40-60= Fat and CHO evenly
75%=mostly carbs
>80%=100% carbs.
upper limits of exercise intensity depends on
rate that cells extract, conserve and transfer chemical energy of food to myofibrils.
what alters rate of E release during chemical reactions?
Enzymes and co-enzymes.
Difference between total O2 consumed during exercise and total that would have been consumed had a steady state of aerobic metabolism be reached immediately from start?
O2 deficit
Energy supplied from O2 deficit is from what?
anaerobic systems (STP/CP/anaerobic glycolysis(LA system))
Who has less O2 deficit? why?
train person. they reach steady state more rapidly.
the time it takes the body to get adjusted to exercise?
circulatory lag.
What is reasoning of circulatory lag?
it is time of production of oxidizable substrate (H+) in which O2 combines.
What does EPOC stand for?
Excess post exercise O2 consumption
AKA O2 Debt.
Vo2 in recovery- VO2 theoretically consumed at rest=
O2 uptake in recovery.
Reflects the anaerobic metabolism of exercise and the respiratory-circulatory-hormonal-ionic-thermal adjustments of recovery
O2 Debt/ EPOC
In submit exercise, recovery is______ and can last ____
rapid
2-3 mins
In stressful exercise, what happens to recovery?
body requires more time to return to rest
can last hours
What is responsible for increasing metabolic rate after exercise?
recover.
