The Cooper Institute

Founded in 1970 by the "Father of Aerobics"
Kenneth H. Cooper MD, MPH


Moderate Means What?

Posted in
Move more

Monday, May 11, 2009

Moderate-intensity physical activity. We’ve used this phrase throughout the Stand Up & Eat blog. Why? Current recommendations for adults are to do at least 150 minutes per week of moderate-intensity physical activity or 75 minutes of vigorous-intensity physical activity per week (or some combo of the two).

Just what does moderate-intensity feel like?

Well, if you’re an exercise physiologist, moderate-intensity is equal to 3.0 to 5.9 METs. A MET is a way of describing the amount of energy (calories) the body is burning relative to energy burned at complete rest. So 1 MET is rest, 2 METs means the body is burning calories at twice the rate of rest, 3 METs is three times, and so on.

OK, that doesn’t help the average person much.

Another way to know if you are exercising at the recommended moderate-intensity level is by rating how hard you think you’re working. Called the “rating of perceived exertion (RPE),” you simply estimate on a scale of 0 (not at all hard) to 10 (extremely hard) what number best matches your effort while exercising. If you rate your physical activity intensity at 5-6, then you are likely doing moderate-intensity exercise. If you rate yourself lower than 5, you would need to pick up the pace a bit.

A similar self-rating strategy is the “talk test.” It goes like this. If you are doing a physical activity and you can sing a song at the same time, you are at a light-intensity level. If you can’t sing but you can still talk fairly comfortably, you are in the moderate-intensity zone. If you are so breathless that you can’t sing or talk, you’re doing a high-intensity physical activity.

The newest method for helping people judge their exercise intensity requires a step counter and a watch. We have blogged previously about the great benefits of using a step counter to get and stay physically active. But one downside to using step counters is that a step is a step whether done at a stroll or a full-bore run. So you may be reaching your daily step number goal but you don’t know if you are attaining the recommended moderate-intensity goal.

New studies1,2 now suggest that if you walk at a pace where you are doing about 1,000 steps in 10 minutes (100 steps a minute), you will be burning calories at the 3 MET, 5-6 RPE, or “talk but not sing” levels. That is, you’re at the moderate-intensity level that is recommended to get health and fitness benefits. Yes, it is a rather crude way to estimate exercise intensity, but scientists believe that it’s practicality outweighs it’s imprecision.

So the next time you go for a walk, check the number of steps on your pedometer and the time on your watch before you head out. When you’re done, divide the number of steps you walked by 100. If this number matches or is more than the number of minutes you walked, then you likely were walking at a moderate (or higher) intensity. Pay attention to how you felt during your walk and aim to do most of your daily physical activities at that same intensity level.

1. Marshall SJ, et al. Translating physical activity recommendations into pedometer-based step goal: 3,000 steps in 30 minutes. American Journal of Preventive Medicine. 2009;36(5):410-415.

2. Tudor-Locke, CE et al. Redometer-based step count guidelines for classifying intensity in a young ostensibly health population. Canadian Journal of Applied Physiology. 2005;30:666-676.