科学美国人60秒:Wearable Step Counters Offer Exercise Leg Up

Sometimes it’s hard to get moving. So setting a goal for the number of steps you walk each day can be a good motivator. But how to keep track of your total? A new study finds that many of the widely available wearable step counters actually keep a pretty accurate count. The research is in JAMA. [Meredith A. Case et al, Accuracy of Smartphone Applications and Wearable Devices for Tracking Physical Activity Data]

For the study, 14 volunteers agreed to walk on treadmills while decked out with 10 popular wearable or smartphone counting technologies. The devices were compared with actual manual counts of either 500 or 1500 steps. So how’d they do? 

Smartphone apps were better step trackers than wearable tech—but the wearables were not terrible either. They typically slightly undercounted, compared to manual tallies, for example.  Some of the discrepancy between the apps and wearables could be because volunteers’ phones were in a pocket close to their hips where it may be easier to pick up specific movements. But in everyday life smartphones would not always be in a pocket, of course.

Of the 10 apps or devices studied, the Fitbit One was most accurate and had good consistency. 

Although none of the counts were that far off—for example, clocking just 1200 steps instead of 1500—the findings suggest that it’s probably a good idea to take the numbers as a loose estimate. And if you can’t walk somewhere, you can still feel motivated to park a few hundred steps away from your final destination.

—Dina Fine Maron 


(The above text is a transcript of this podcast)