The Metabolic Equivalent of Task, or MET, is a unit that measures the energy cost of physical activities. One MET is defined as the energy expended while sitting quietly, which is approximately 3.5 milliliters of oxygen per kilogram of body weight per minute. Activities can be classified by their MET values, helping to compare the intensity of different exercises. For example, walking at a moderate pace may have a MET value of around 3 to 4, while running can range from 8 to 12 METs, depending on speed. Understanding MET values can assist individuals in planning their workouts and managing their energy expenditure effectively.