Fitness Trackers' Accuracy Depends on Exercise
Wristband activity monitors such as those by Fitbit, Garmin, and Jawbone can help you monitor your fitness, but a study says their accuracy depends on the physical activity you do. Researchers asked 30 adults to wear a device from all three manufacturers on each wrist while using a treadmill and performing various activities. With the treadmill, all of the brands were more than 90 percent accurate and performed best at faster treadmill speeds. All of the monitors under-counted steps during stroller-pushing—presumably because the arms are kept still—but over-counted for laundry-folding, as that involves wide arm movements. The devices were less accurate when worn on the person’s dominant wrist. So if you’re right-handed, strap your monitor onto your left wrist, and vice versa.
Source: Medicine & Science in Sports & Exercise, published online May 13, 2016