Question

What is the approximate rate of oxygen utilization of an individual performing a steady exercise on a cycle ergometer at 100 w if his metabolic rate is 6.8 Kcla/min, the rate of CO2 expiration is 1.2 L/min and respiratory exchange ratio is 0.88?

Answer 1

GIVEN:

Work rate = 100 watts = 100 kg/meters min

Metabolic rate= 6.8 kcal/min i.e RER caloric eqivalent * VO2(L/min)

Rate of CO2 expiration (VCO2)= 1.2 L/min

Respiratory exchange ratio(RER)=0.88

TO FIND: Rate of oxygen utilization (VO2)(L/min)

SOLUTION:

W.K.T RER= rate of CO2 expired/ rate of O2 consumed(i.e VCO2/VO2)

0.88=1.2 L/min/VO2

VO2=1.2 L/min/0.88

VO2=1.36L/min

Thus the rate of oxygen utilized during steady state exercise at cycle ergometry is 1.36 L/min.