|Basic InformationLatest News|The Top 5 Conditions That Shorten Americans' Lives -- And Are Preventable4 in 10 Americans Still Breathe Dirty AirDon't Let Bugs Dampen Your Outdoor FunPeripheral Vision Varies From Person to Person'I'm Just Too Busy' -- Is Being Overworked the New Status Symbol?Americans Are Spending Billions Nipping and TuckingThese 5 Life Skills Can Boost Your Odds of Well-BeingDon't Bank on Heart-Rate Accuracy From Your Activity TrackerHow to Protect Yourself From Air PollutionGood Sleep Does Get Tougher With AgeGuys, a Good Night's Sleep Might Save Your LifeHealth Tip: Overcoming Dental AnxietyHealth Tip: Spring Cleaning?Health Tip: Talk to Your Doctor About Emotional StrugglesNeed More Zzzzz's?Single Dose of SSRI Prompted Healthy Food Choices During TestDaily Glass of Beer, Wine Might Do a Heart GoodShorter Winter, Longer Spring?Health Tip: Stay Focused on the HighwayHealth Tip: Don't Contaminate Contact LensesParenthood an Elixir for Longevity?Your DNA May Determine How You Handle the Time ChangeHow to Keep a Spring in Your Step With Daylight Saving Time'Pokemon Go' Players Add 2,000 Steps a DayFewer Americans Actively Trying to Lose WeightCan Social Media Sites Leave You Socially Isolated?Hispanics Should Be Wary of the Sun's Rays, TooDaffodils, Margaritas and Other Surprise Skin DangersDo 'Early Birds' Get the Healthier Worm?Health Tip: Use Caution When Applying Hair DyeHow Much Melatonin Is Really in That Supplement?Health Tip: Learn Your Prime Sleep TimeLive Healthy, Live LongerA Stressed Life May Mean a Wider WaistlineU.S. Life Expectancy May Rise to Over 80 by 2030Ready for Spring Break? Have Fun But Play It SafeVitamin D Pumps Up MusclesPossible Drawback to Gluten-Free: Toxic MetalsAmerica in 2017: Pass the Prozac, PleaseSome Partners Need Extra Loving This Valentine's DayThe 'Selfie' ParadoxBeware Heart Attack Risk From Shoveling SnowHow to Stay on Your Feet During Slippery Winter ConditionsPop! Goes That Balloon, and Maybe Your HearingHealth Tip: Daily Routine Can Minimize StressHealth Tip: Going Outside in Winter WeatherSkimp on Sleep and You Just May Wind Up SickWinter's No Reason to Hibernate: Head Outside for Some Sports FunFor Millions of Americans, Everyday Life Takes Toll on Their HearingHealth Tip: For Better Sleep, Watch What You EatLinksBook Reviews
Don't Bank on Heart-Rate Accuracy From Your Activity Tracker
by By Randy DotingaHealthDay Reporter
Updated: Apr 10th 2017
MONDAY, April 10, 2017 (HealthDay News) -- Wrist-worn activity trackers such as Fitbit don't reliably assess heart rate, a new study finds.
While the devices may have some legitimate benefits, they shouldn't be used for medical purposes, researchers suggest.
Evaluating four wearable activity trackers from Fitbit, Basis and Mio, the investigators compared results to those from an electrocardiograph (EKG). The researchers found results varied among the different models, and were much less accurate during exercise than at rest.
"These devices are probably good enough to inform consumers of general trends in their heart rate -- high or low -- [but] it's important to have more accurate information when physicians are relying on this data to make decisions on medications or other tests and treatments," said Dr. Mitesh Patel.
Patel is an assistant professor of medicine and health care management at the University of Pennsylvania. He wasn't involved in the study.
However, the study's lead author cautions against making too much of the discrepancies.
"At any moment, the tracker could be off by a fair bit. But at most moments, it won't be," said Lisa Cadmus-Bertram, an assistant professor of kinesiology at the University of Wisconsin at Madison.
"The heart-rate feature performed better at rest," she said. "They're not as precise during exercise."
A 2014 survey by PricewaterhouseCoopers found that 20 percent of American adults owned a wearable activity tracker.
For the new study, 40 healthy adults, aged 30 to 65, were recruited to test the Fitbit Surge, Fitbit Charge, Basis Peak and Mio Fuse.
Generally, when compared with the EKG results, the activity trackers were near the correct mark, Cadmus-Bertram said. But occasionally, their estimates of heart rate could swing too high or too low.
At rest, the Fitbit Surge was most accurate; Basis Peak was least accurate, the study authors said.
During exercise on a treadmill at 65 percent of maximum heart rate -- defined as 220 beats per minute minus age -- accuracy suffered more.
The monitors could overestimate heart rate by as much as 39 beats per minute (Fitbit Surge), or underestimate it by as much as 41 beats per minute (Fitbit Charge), the study found.
The findings support those of a study released last month at the American College of Cardiology annual meeting. Depending on the type of activity, the wrist devices were up to 34 beats per minute off, those researchers found.
Again, the devices were least accurate during exercise.
Some wrist-worn activity trackers use a light-emitting diode, or LED, that measures heart rate by detecting changes in the amount of blood in the skin.
Patel said accuracy may be a problem because the devices move around on the arm, especially during exercise.
Meanwhile, Fitbit's maker said its fitness trackers aren't intended to be medical devices. The company issued a statement in response to the new study.
"We conducted extensive internal studies which show that Fitbit's PurePulse technology performs to industry standard expectations for optical heart rate on the wrist," the statement said. Moreover, "Fitbit devices were tested against properly calibrated industry standard devices like an EKG chest strap across the most popular activities performed worldwide -- including walking, running, biking, elliptical and more."
Cadmus-Bertram cautioned that the data for the new study were collected about a year ago.
"Not only have newer models since been released, but the algorithms behind the data are presumably being updated and improved on a regular basis," she said. "So the results we found might be different if we did the study again now."
In general, she's remains a fan.
"On the whole, fitness trackers still provide a tremendous amount of useful information to the average user who just wants some feedback to help them to increase their exercise level," Cadmus-Bertram said.
The study findings were published online April 11 in the Annals of Internal Medicine.
For help staying active at any size, see the U.S. National Institute of Diabetes and Digestive and Kidney Diseases.
This article: Copyright © 2017 HealthDay. All rights reserved.