50 Cardiorespiratory Conditioning
Other Terms for Work Rate
Other terms are frequently used to describe exercise intensity and work rate. These
include:" Work
" Power
" METS
" Watts
If these terms and concepts are learned, they will apply to almost all exercise
equipment and conditioning programs. The terms work and power are often used
incorrectly. Because these terms can be expressed in a variety of ways, it is useful to
understand or at least be familiar with the basic units of measurement.Work and Power
Work = Force x Distance and is measured in kcal
Power = Rate of Doing Work and is measured in watts
METs and Watts
The term MET, which was used in the national recommendations for exercise, is
often used to estimate energy expenditure and work rate.A MET is defined as a multiple of resting
metabolic rate or energy expenditure.One MET is between 0.200 to 0.250 liters (of oxygen)/min, or approximately one
kcal/min, depending on the weight and body type of the person. Two METS would be two
times resting metabolic rate or approximately 0.5 liters (2 X 0.200 to 0.250) of oxygen/min,
or 2 kcal/min. Likewise, 3 METS would be 0.75 liters (3 X 0.200 to 0.250) of oxygen/min,
or around 3 kcal/min.