ergonomics aids exam one

Role of mitochondrial respiration during exercise

Produce long-term ATP and replenish PCr

ATP has what kind of supply

Limited

Mitochondrial respiration has what kind of supply

Virtually unlimited

Why is continuous synthesis of ATP necessary for muscle contraction?

muscle contraction can increase ATP demand by 100 so it must be continually synthesized to fuel activity

What are the three energy systems and which ones are considered anaerobic?

PCr (anaerobic) glycolysis (anaerobic), and mitochondrial respiration (aerobic)

How long can the PCr systems supply energy during an all out sprint ?

10 to 15 seconds

What is the role of mitochondrial respiration during exercise?

To produce long term ATP and replenish PCr

Stimulates metabolic pathways to speed up

High ADP levels

Causes hitting the wall

Low glycogen levels; forces slow fat oxidation

PCr system provides energy for…

2-3 seconds for max effort

Which energy system has the highest rate of ATP production

PCr

Entry point to TCA cycle

Acetyle CoA

Net ATP yield from glycolysis using blood glucose

2

Main reason fat is not used during high intensity exercise

Needs oxygen which is limited

Fat ____ is a ____ process requiring ____ amounts of ____ which ____ keep pace with the rapid energy demand

Metabolism, Slow, high, oxygen, cannot

Molecule that acts as the final electron receptor in the electron transport chain

Oxygen

How many ATP does complete oxidation of one glucose molecule produce

32

what stimulates energy production in the cell; turns pathways on

High ADP levels

Process that breakdown fatty acid into two carbon units

Beta oxidation

What is the body‘s main energy currency and how long is it stored for max efforts?

ATP ; 2-3 seconds

How long does the ATP PCR system last?

10-15 seconds

net ATP produced from glycolysis using blood glucose

2

net ATP from glycogen breakdown

3

The body’s primary way to store glucose for quick energy

Glycogen

Primary fuel source for producing ATP

Glucose

What is the rate limiting enzyme for glycolysis?

PFK

glycogen depletion causes…

“Hitting the wall”

Explain how the phosphine and oxidative systems work together

By providing immediate power for high intensity movement while simultaneously allowing the body to recover and prepare for future action

Define the crossover point

The intensity at which energy from carbs begin to dominate over energy from fat

What is the primary effect of endurance training on the crossover point?

The body can adapt to Use fat as a major fuel at higher intensities rather than carbs

Low intensity, long duration activities are fueled almost entirely by which system

Aerobic (mitochondrial respiration)

Lactate

Important fuel (not waste)

At low intensities, this is the main fuel source

Fat

At high intensities, this is the main fuel source

Carbs

The CP concept describes the shift from __ to __ as exercise intensity increases.

Fat, carbs

What causes the crossover shift toward carb use at higher intensities?

The activation of fast-twitch muscle fibers and higher muscle contraction intensity, which triggers rapid glycogen breakdown, and epinephrine (adrenaline) increases

endurance training shifts the crossover point in which direction?

Right (because trained athletes can work harder before switching to carbs)

Glycogen sparing occurs mainly because trained athletes….

can use more fat at a given workload, slowing glycogen use

At high exercise intensities, the main fuel source is:

Carbs

Lactate threshold represents the point where lactate :

Appears faster than it can be cleared

What is lactate’s primary role in the body during exercise?

Serves as a preferred fuel for many muscles like the brain and heart

The gas exchange threshold (GET) is detected when:

CO2 rises disproportionately

Critical power separates which two intensity domains

Severe and heavy

When exercising above CP, what happens

Vo2 keeps rising, PCr decreases, lactate accumulates, fatigue becomes inevitable

What causes glycogen sparing after endurance training

Increased fat oxidation and mitochondria

What is the primary role of phosphocreatine in the phosphate energy system?

to rapidly donate a phosphate group to ADP, reforming ATP for immediate use

Describe the relationship between the rate of ATP production and the total capacity of the body is three energy systems

Systems with the highest rate of ATP production, like the phosphogen system, have the most limited capacity

why is the gas exchange threshold valuable in clinical settings?

It’s effort independent, making it a reliable and objective measure of metabolic stress and surgical risk.

TCA cycle primary role

To complete the oxidation of acetyl-CoA and harvest high-energy electrons for the electron transport chain

Why does the complete oxidation of a fatty acid like palmitic acid yield more ATP than a molecule of glucose?

The breakdown of fatty acids produces a much larger number of acetyl-CoA molecules

the body’s most immediate source for regenerating ATP (type of system)

phosphagen system