Washington, Jan 21 (IANS): The wristband that you wear believing that it is tracking your fitness and sleep habits may be misleading you.

Many fitness trackers generally measure the number of steps you take every day, the calories you burn and your sleep habits - with some trackers even claiming to measure the time you spend in each stage of sleep, said a report on LiveScience.com.

However, sleep experts say they are sceptical of fitness wristbands’ accuracy in measuring sleep.

Fitness trackers’ ability to measure sleep often comes from sensors called accelerometers, which detect a wearer’s motion, along with the speed and direction of that motion.

“As far as distinguishing sleep stages, trackers that include only an accelerometer as their sensor, can’t do what they claim,” Hawley Montgomery-Downs, a sleep researcher and associate professor at West Virginia University, was quoted as saying.

That’s because although an accelerometer monitors your movement, “you move the same amount whether you’re in deep sleep, or lighter stages of sleep”, Montgomery-Downs added.

Experts worry there may be a danger in consumers putting too much trust in these devices to accurately monitor sleep, especially users who have sleep disorders.

For people without sleep disorders, using a fitness monitor to track sleep isn’t going to hurt or help them, the report added.

But for someone with a sleep disorder, tracking sleep with one of these monitors might give them a false reassurance, she said.