Lecture 7

Question 1

Why does ventilation increase during exercise?

Answer 1

Due to higher demand for oxygen

Question 2

What is the ventilatory threshold?

Answer 2

The point at which ventilation increases disproportionately to oxygen consumption
-Typically same point when lactate starts to accumulate in the blood
-Lactate being buffered by bicarbonate into CO2, which must be expired to prevent acidosis

Question 3

Steady state exercise

Answer 3

Stable levels of O2 consumption and CO2 production
-Can only be achieved if exercise is below ventilatory threshold

Question 4

How long after exercise intensity changes for body to reach steady state for VO2 and VCO2?

Answer 4

VO2: 2 mins
VCO2: 3 mins

Question 5

True or False: Highly fit individuals develop lactic acidosis at lower power outputs than sedentary individuals

Answer 5

False! Fit individuals develop lactic acidosis at higher power outputs than sedentary individuals

Question 6

When changing exercise intensities, what adjusts faster? O2 consumption or CO2 production?

Answer 6

O2 consumption adjusts faster than CO2 production when adjusting intensities

Question 7

How many mls of CO2 released for every mmol of HCO3 buffering lactate?

Answer 7

22mls