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(Reuters Health) - Smartphones and fitness bands are decent step counters, a small study finds, suggesting that millions of people who use these devices can reliably track how far they run or walk as they work to improve their health.
The newer gadgets aren't as accurate as old-school pedometers, but they are ubiquitous. Smartphones can run step-counting apps, and fitness bands and other wearable health devices are gaining in popularity as more people use them to help with weight loss or getting in shape.
“Overall, smartphones and wearables are accurate for the purposes that many people need, especially for sedentary people who need to increase their activity because they are overweight or obese and simply need to know if they reached the minimum amount of activity needed to maintain good health,” said lead study author Dr. Mitesh Patel of the University of Pennsylvania in Philadelphia, in a phone interview with Reuters Health.
While tracking on its own can't necessarily improve health, 30 minutes of moderate activity most days of the week can reduce the risk of obesity, cardiovascular disease, diabetes, and some cancers as well as help strengthen muscles and bones, according to the U.S. Centers for Disease Control and Prevention.
To test the accuracy of steps recorded by smartphones and wearable devices, Patel and colleagues got 14 volunteers to walk on treadmill set to a 3.0 mile-per-hour pace for 500 steps and again for 1,500 steps, repeating each distance twice.
Participants walked while wearing a pedometer, the Digi-Walker SW-200; two accelerometers, the Fitbit One and Fitbit Zip; and three popular fitness wristbands, the Nike FuelBand, Jawbone UP24, and Fitbit Flex.
In one pocket, they had an iPhone 5s simultaneously running three apps: Fitbit, Health Mate, and Moves. In the other pocket, they had a Galaxy S4 running Moves.
Researchers counted steps by direct observation and then checked to see how close the smartphone apps and wearable devices came to reaching the same number of steps.
As reported in the Journal of the American Medical Association, the pedometers and accelerometers did the best, on average missing the observed step count by 1 percent or less.
Smartphones on average recorded from 6.7 percent fewer steps to 6.2 percent more, with iPhone apps slightly over-counting and the Galaxy app slightly under-counting.
The fitness wristbands under-counted, ranging from 1.5 percent to 22.7 percent fewer steps, with the FuelBand deviating the most.
"It's true we found some variation, but I would also say that our findings should be reassuring to people who want to use smartphone apps or wearables to track their activities," Patel said.
If cost is a consideration, people who already have a smartphone might want to try the apps before investing in a fitness band, which can retail for more than $100, said Dr. David Geier, an orthopedic surgeon and sports medicine specialist based in Charleston who wasn't involved in the study.
For people who don't have a smartphone, a simple pedometer might cost $10 to $30, he said.
"It's tremendously helpful for motivation to have a realistic understanding of where you actually are and then track your own improvement," Geier said. "Tracking on its own won't make you lose weight or get healthier, but it can certainly help you get closer to at least the recommended 10,000 steps a day which very few people currently achieve."
Where motivation is concerned, smartphones and fitness bands have a clear advantage over pedometers because there's a potential for users to share results with friends on social media, said Heather Milton, Senior Exercise Physiologist at NYU Langone Medical Center’s Sports Performance Center.
"The impact of integrating social aspects to fitness has been proven time and time again to enhance adherence and success of healthy behavior change," said Milton, who wasn't involved in the study. "Whether it is support for some or the competition for others, this is a huge element of improving activity and health."
Even if the device isn't quite as accurate as a pedometer, it's still better than not tracking steps at all, she said.
Using these devices "increases mindfulness, a key to behavior change,” she added. “It is for this reason that people opt to walk rather than ride an elevator or escalator, or get up and walk every few hours at work."
SOURCE: bit.ly/1A99AFH JAMA, online February 10, 2015.