Define the term 'metabolic equivalent' (MET).

The term 'metabolic equivalent' (MET) refers to a unit that estimates the amount of oxygen used by the body during physical activity. Specifically, one MET is defined as the rate of energy expenditure while at rest, which is approximately equal to 3.5 milliliters of oxygen consumed per kilogram of body weight per minute. This measure allows for the comparison of the energy cost of various physical activities relative to resting metabolic rate.

Using METs enables fitness professionals and individuals to gauge the intensity of different exercises effectively. For example, activities with higher MET values indicate a greater demand for oxygen and, consequently, a higher energy expenditure than activities with lower MET values. Understanding this concept is essential for developing effective exercise programs and assessing cardiovascular fitness.

Other options, while relevant to fitness and health, do not accurately define MET: measures of muscle strength, body fat percentage, and heart rate involve different physiological metrics and serve unique purposes in fitness assessments.