new report says fitness trackers are not so accurate in measuring amount of calories our body burns while exercising, and that this may lead people to make poor decisions about their diet. study is from Stanford University in USA. Researchers evaluated accuracy of five popular trackers. These included Apple Watch, Microsoft Band, Fitbit Surge and Samsung Gear S2. researchers observed 60 volunteers as they walked, ran and cycled while wearing devices. Researchers found that none of devices had error rate below 20 per cent. Dr Euan Ashley, co-author of study, said: "People need to know that on energy expenditure, [ trackers] give rough estimates."
Stanford scientists said users of fitness trackers should be cautious about using devices to judge what they eat. Dr Ashley said: "If you go to gym, and you think you've lost 400 calories, then you might feel you've got 400 calories to play with." This could be problem for those who base what they eat on how many calories their fitness tracker said they burned. One CEO of fitness tracker company suggested researchers may not have adjusted the user settings properly. CEO told the USA Today newspaper that study method could have reported incorrect data, saying: "We think excess error reported in energy expenditure is not representative in this study, due to this methodological error."