Question

4.If Bob (200 lbs) and Jan (145 lbs) both perform 20 minutes of moderate-intensity elliptical trainer exercise, which has a MET value of 4.9, who will expend more energy? Why?

5. What is Bob’s oxygen consumption rate (L/min)?

6. What is Jan’s oxygen consumption rate (L/min)?

7. On average, how many kilocalories (kcals) are expended for every liter (L) of oxygen consumed?

Answer 1

4: One METS is defined as the amount of oxygen which is consumsed by body at rest. It is nearly 3.5 ml oxygen/kg body weight/min. So, to perform the same activity, a person with more body weight would expend more energy.
Calories = METS x weight (kg) x time (hours)
Calories expenditure by Bob= 4.9 x 90.71 kg x 0.33 hour= 146.67 calories
Calories expenditure byJan= 4.9 x 65.77 kg x 0.33 hour= 106.35 calories

So, Bob spent more energy on the said activties due to high higher body weight.