A number of wrist-worn fitness and heart rate monitors exist to provide heart readings and help guide a person's physical activity. But there is variable accuracy among these monitors, according to a new study published Wednesday in JAMA Cardiology.
The study, which tested the Apple Watch, FitBit Charge HR, Basis Peak and Mio Alpha wristbands, found none of the wrist-worn heart rate monitors achieved the accuracy of a chest strap-based monitor. And generally speaking, accuracy of wrist-worn monitors was best at rest and diminished with exercise.
Fifty healthy adults recruited for the study were assessed while at rest and at various speeds on a treadmill. Researchers found that the Apple Watch and Mio Fuse did best overall, with about 91 percent accuracy, according to NPR.
The other wrist-worn monitors came out in the 80 percent accuracy range, both overestimating and underestimating wearers' heart rates, according to the report.
Marc Gillinov, MD, a cardiac surgeon at the Cleveland Clinic and an author on the study, said such errors are not a huge deal for most people, although for elite athletes and cardiac patients who try to keep their heart rates in certain ranges, these devices may not be the best choice, according to NPR.
"For those groups, I'd recommend medical-quality chest-strap monitors," he said.