Taryn Duchene wears a Fit Bit fitness band everyday.
"I mainly look at the steps and the distance,” she says.
And more and more people are forking over a hundred dollars or more for the devices.
"There's like new monitors that come out in the market everyday,” says Yang Bai, a ISU Ph.D. student.
The wristbands come packaged with promises of a healthy lifestyle.
They can track how many calories your burn when you sleep, workout and sit.
"Most of these devices are released with very little information on validity consumers just by them because they look interesting and they're fun,” says Greg Welk, ISU kinesiology professor.
An Iowa State kinesiology study finds none of the fitness bands on the market are 100 percent accurate.
"You can get the same kind of self monitoring benefit from a $25 pedometer,” says Welk.
Researchers tested eight devices for their accuracy in tracking calories burned.
"A lot of the technology now is pretty advanced now on how to detect patterns in the movement and the error is within you know 12 to 15 percent,” says Welk.
The BodyMedia FIT was the most accurate, with a 9.3 percent error rating. The Basis band has the lowest rating at 23.5 percent.
Even then, ISU researchers say they can be a good motivational tool.
"If a person thinks is going to help them adopt and maintain an active lifestyle then it probably has value for them,” says Welk.
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