NEW YORK, NY - JUNE 18: The line of Fitbit products are displayed during a lunchtime workout event outside the New York Stock Exchange during the IPO debut of the company on June 18, 2015 in New York City. According to reports, shares of Fitbit, which makes wearable fitness tracking devices, rose significantly on Thursday after debuting as a public company on the New York Stock Exchange. Eric Thayer/Getty Images/AFP == FOR NEWSPAPERS, INTERNET, TELCOS & TELEVISION USE ONLY ==
Wrist-worn activity trackers, increasingly popular among consumers and in healthcare research, can vary considerably in their accuracy, a study from Iowa State University suggests.
Researchers pitted consumer devices against a gold-standard metabolic monitor and found the wristbands are more accurate for calories burned while resting or jogging, but have higher error rates for activities like weight lifting and crunches.
