Oxygen consumption is measured in METS; energy expenditure is measured in which unit?

• A. METS
• B. Kilocalories (kcals)
• C. Liters per minute
• D. Heart rate

Answer: (B)

Energy expenditure is measured in kilocalories because it reflects the actual amount of energy the body uses. Oxygen consumption, on the other hand, is expressed as METs, which describe relative exercise intensity based on resting oxygen uptake. To connect the two, you can estimate calories burned by multiplying the MET value by body weight (in kilograms) and the duration (in hours). For example, at 5 METs for 1 hour in a 70 kg person, roughly 5 × 70 × 1 ≈ 350 kilocalories are expended. The other options don’t represent energy units: liters per minute measures the volume of oxygen used, and heart rate is a physiological marker, not an energy measure. So kilocalories is the appropriate unit for energy expenditure.