oxygen consumption

• Oxygen consumption (how much oxygen we have)

  ⭐: the amount of oxygen the body is currently taking in, transporting and utilising to produce energy

  • Adapts to the fluctuations in exercise intensity
• Oxygen demand (how much oxygen we need)

  ⭐: the amount of oxygen the body needs to sustain the exercise intensity

  • When we begin exercising:

  ↑atp demand -> ↑oxygen demand -> ↑oxygen consumption

  • When we stop exercising:

  ↓atp demand -> ↓oxygen demand -> ↓oxygen consumption

  *fluctuations in exercise intensity will lead to fluctuations in demand
• States of oxygen consumption

  1. Oxygen deficit
  2. Steady state
  3. EPOC
• Oxygen deficit

  ⭐: oxygen supply DOES NOT meet oxygen demand (not enough oxygen)

  • We experience oxygen deficit because cardiovascular system needs time to meet oxygen demand to increase oxygen consumption, but while body tries to catch up we are at oxygen deficit
  • This happens when there is a sudden increase in intensity e.g. rest to motion
  • The body will see an increased reliance on the anaerobic pathways to meet the ATP demand until the oxygen demand is met
• Steady state

  ⭐: oxygen supply equals the oxygen demand

  • Can take anywhere from a few seconds to one minute or more to reach a steady state
  • Aerobic pathways make an increase contribution
  • Anaerobic pathways still make a very small contribution to ATP production
  • Exercise intensity + training status (individual constraints) determines how long it takes to reach a steady state
• EPOC (excess post-exercise oxygen consumption)

  ⭐: when the body’s oxygen supply exceeds the oxygen demand

  • At the completion of exercise, the demand for ATP decreases dramatically, however, oxygen consumption remains elevated above resting levels
  • Allows body to return to pre-exercise conditions more efficiently via:
  • Increased O2 allows replenishment of PC stores
  • Allows more efficient oxidation and removal of metabolic byproducts
  • Elevated heart rate assists with thermoregulation and reduction in body temp.
  • Oxygen is restored to myoglobin more efficiently