Cardiopulmonary Exercise Testing & Aerobic Limits (Wk 1)

What is the simplified O₂ pathway through the body?

Lungs → O₂ on Hb → heart pumps through vessels → mitochondria.

What is the primary limiting factor for aerobic exercise in normal healthy individuals?

Cardiac output (O₂ delivery).

What is the primary limiting factor for aerobic exercise in some elite endurance athletes?

The pulmonary system (exercise-induced arterial hypoxaemia).

What does EIAH stand for in exercise physiology?

Exercise-induced arterial hypoxaemia.

What does the Fick equation (VO₂ = Q × [CaO₂ − CvO₂]) calculate?

Oxygen consumption via cardiac output multiplied by a-vO₂ difference.

How is arterial oxygen content (CaO₂) measured?

Via radial artery puncture.

Why is mixed venous oxygen content (CvO₂) very hard to measure?

It requires sampling all blood returning to the right heart via catheter.

What is a typical resting cardiac output for humans?

Approximately 5 litres per minute.

Who was the first to measure VO₂max using Douglas bags?

A.V. Hill (Nobel Prize winner).

What happens to VO₂ as running speed increases to maximum?

It rises until it plateaus, defining VO₂max.

What does absolute power output primarily reflect in an athlete?

Muscle cross-sectional area.

Why is relative VO₂max (per kg) important in endurance sports?

For sports where athletes must carry their own body weight.

Which sport category generally records the highest VO₂max values?

Cross-country skiing.

Which sports typically show low VO₂max values?

Weightlifting and fencing.