A patient walks at a very brisk pace (4 mph), which equals 5.0 METs. What is the correct intensity classification?

• A. Moderate
• B. Near-maximal
• C. Light
• D. Vigorous

Answer: (A)

Metabolic equivalents (METs) classify exercise intensity by energy cost: light is about 1.6–2.9 METs, moderate is 3–5.9 METs, and vigorous is 6 METs and above. A brisk walk at 4 mph is roughly 5.0 METs, which falls squarely in the moderate range. This level means you’re elevating heart rate and breathing enough to notice effort, but you can still talk in phrases (not sing). Near-maximal would imply a much higher effort close to your max, which isn’t indicated by 5.0 METs. So the correct classification is moderate.