Exercise Physiology

What is cardiac output?

The total amount of blood pumped by the heart each minute.

What is stroke volume?

The amount of blood pumped from the left ventricle per beat (~70 mL)

What is heart rate?

The number of times the heart beats per minute.

What is blood pressure?

The force exerted by the blood on the artery walls as it is pumped through the body.

What is respiratory rate?

The number of breaths a person takes per minute.

What is perspiration?

The release of liquid from the body’s sweat glands as a result of exertion.

What is blood redistribution?

The redirection of blood flow during exercise to working muscles rather than inactive regions.

What is the meaning of resynthesise?

The process of replenishing energy depleted during physical activity.

What are the 6 immediate cardiovascular responses to physical activity?

Increased cardiac output, stroke volume, heart rate, blood pressure, a-VO₂ difference, and blood redistribution.

What are the 3 immediate respiratory responses to physical activity?

Increased tidal volume, gas exchange, and respiratory rate.

What is ventilation and how is it calculated?

The amount of air inspired and expired in 1 minute (tidal volume x respiratory rate)

What is tidal volume?

The amount of air breathed in and out in one breath.

What is a-VO₂ difference?

The difference in oxygen volume between blood in the arterioles and venules.

What are the 6 long-term cardiovascular adaptations to training?

Increased stroke volume, capillarisation, cardiac output and haemoglobin, decreased heart rate and blood pressure.

What are the 4 long-term respiratory adaptations to training?

Increased tidal volume, gas exchange, VO2 max, and ventilation.

What is the ATP-CP energy system?

The adenosine triphosphate - creatine phosphate system. The body’s immediate energy system that doesn’t require oxygen.

What is the fuel source of the ATP-CP system?

ATP and CP stored in muscle cells.

What type of intensity is the ATP-CP system used for?

Very high - >95% max HR

What is the rate and yield of ATP production in the ATP-CP system?

Very fast rate, small yield (<1 ATP)

What are the byproducts of the ATP-CP system?

ADP, inorganic phosphates (Pi)

What is the total duration of the ATP-CP system?

Up to 10 seconds (ATP lasts for 1-2, CP lasts for 7-8)

What is the fatigue rate of the ATP-CP energy system?

Fast, 5-10 seconds.

2 examples of activities for which the ATP-CP system is used

100m sprint, long jump.

3 advantages of the ATP-CP system

Resynthesises ATP immediately, doesn’t need long chemical reactions, used for high-intensity activities.

2 disadvantages of the ATP-CP system

Resynthesises a very limited amount of ATP, limited stores of ATP and CP in muscles.

What is capillarisation?

The process of forming new capillaries around the tissues in the lungs and heart.

What is ATP?

Adenosine triphosphate. A chemical compound stored in the cells that produces energy for movement.

How does ATP turn into ADP + Pi?

One of the bonds between the phosphate molecules attached to the adenosine molecule breaks, releasing energy for movement and leaving adenosine diphosphate and an inorganic phosphate molecule.

What are the 3 energy systems?

ATP-CP (alactic), Anaerobic glycolysis (lactic), Aerobic.

What is the anaerobic glycolysis/lactic acid system?

An energy system that relies on the breakdown of glycogen, in the absence of oxygen, to produce energy.

What is the fuel source for the anaerobic glycolysis system?

Glycogen (stored form of glucose)

What intensity of exercise is the anaerobic glycolysis system used for?

High intensity, over 85% max HR.

What is the rate and yield of ATP production in the anaerobic glycolysis system?

Fast rate, small yield (2-3 ATP)

What are the 3 byproducts of the anaerobic glycolysis system?

Lactic acid, hydrogen ions, adenosine diphosphate.

What is the total duration of the anaerobic glycolysis system?

10-75 seconds.

What is the fatigue rate of the anaerobic glycolysis system?

30 seconds - 2 minutes.

2 examples of physical activities in which the anaerobic glycolysis system is used?

400m run, 100m swim.

1 advantage of the anaerobic glycolysis system

Resynthesises ATP quickly, allowing for high-intensity efforts.

3 disadvantages of the anaerobic glycolysis system

Produces hydrogen ions which cause fatigue in large amounts.
Slow recovery
Only capable of producing small amounts of ATP.

What is aerobic glycolysis?

The breakdown of glycogen in the presence of oxygen to produce energy, carbon dioxide, water and heat.

Why does the aerobic system take time to get going?

Several processes need to occur - lungs work harder to bring in more oxygen, heart pumps harder to transport more oxygenated blood to the muscles, arteries expand to increase blood flow.

What are the sources of fuel for the aerobic system and in which cases are each used?

Fats - used for low to moderate intensity

Glycogen - used for moderate to high intensity

Protein - used for extreme situations when glycogen and fats have run out.

At what intensity is the aerobic system used?

Resting and sub-maximal - less than 80% max HR>

What is the rate and yield of ATP production in the aerobic system?

Slow rate, largest yield (36-38 ATP per mole of glucose, >100 ATP per mole of fat)

What are the 3 byproducts of the aerobic system?

Carbon dioxide, water, heat.

What is the duration of the aerobic system?

75+ seconds.

What is the fatigue rate of the aerobic system?

Slow - 2+ minutes.

What is fatigue rate?

The speed at which an athlete’s performance declines due to the depletion of fuel sources or build-up of byproducts.

3 examples of physical activities in which the aerobic system is used

Marathon, triathlon, mid-field AFL player.

2 advantages of the aerobic system

Resynthesises large amounts of ATP
Produces non-fatiguing byproducts.

What is diffusion?

The movement of gases from areas of high to low concentration.

What is energy system interplay?

The combined, overlapping contribution of energy systems to produce ATP.