As I've started to dive deeper into the data some of the health tools I'm testing, I've come across a term that was new to me - MET. This is an acronym that stands for "metabolic equivalent of task". This is a standard measure of energy expenditure and oxygen consumption. It's also one of the data points that the BodyMedia FIT armband and FitBit use to gauge your physical activity.

A MET is a way by which we can compare activities. As example, someone who is being a couch potato and watching the baseball playoffs has a metabolic equivalent of 1 whereas the baseball player on the field being watched is closer to a metabolic equivalent of 5.

Displaying MET Information

Although both products use METs, they display the information in different ways. In the case of the BodyMedia armband, they show METs on an hourly timeline. You can use the slider to isolate a time window and see your average METS and calories burned. The screen snap below shows a time window for me from 6AM to 10PM. You can quickly see when I was more active by observing the spikes. Conversely, you can see that my metabolic equivalents are much lower when I'm sleeping or in front of the computer.

The FitBit system also references METs but in a different fashion by presenting an overall active score. The daily score starts at 0 and hopefully increases as you get more active during the day. It doesn't include food intake. The company indicates that the score is a rough translation of your average METs for the day (METs = Active Score x .001 + 1).

Both programs allow me to set goals or targets around these metabolic equivalents. In the case of BodyMedia, I set a target of how many moderate activities and vigorous activities minutes per day. A moderate activity is defined as between 3-6 METs and a vigorous activity is defined as 6+ METs.

 

The FitBit also allows me to target a daily Active Score. As example, I might shoot for a daily active score of 750.

One thing I don't see in either program is the ability to isolate the MET scores and report on them over time. I know I would like to be able to plot my progress in this category. I've still got much more testing so maybe the feature is buried someplace.

Sample Metabolic Equivalents (METs) Scores

And if you prefer not to be a couch potato, here are some scores for various activities:

Activity	METS
Stationery Bike	7.0
Bicycling < 10MPF	5.0
Descending stairs	3.5
Walking the dog	3.0
Wii Fit	2.3
Playing Piano	2.3
Household walking	2.0
Sitting light office work	1.5
Meeting	1.5
Lying quietly and watching TV	1.0
Sleeping	.95

Bottom line is get moving. You can also find a detailed metabolic equivalents table at https://google.com/site/compendiumofphysicalactivities/home that has hundreds of listings.