It turns out that some fitness trackers are a lot like that blonde American fitness model decked out in the barely-there lycra you follow on Instagram: they look great, but they’re not always too sharp.
Researchers at Australia’s University of New South Wales placed five popular activity trackers under the microscope — the Fitbit One, Fitbit Charge HR, Fitbit Flex, Jawbone UP24, and Actigraph accelerometer — and learned that their accuracy can waver.
The wearable tech market is surging — Forbes reckons it charged past $14 billion last year, and will hit $34 billion by 2021, as more than 125 million devices are shipped around the world — as a generation of couch potatoes are desperate to check that they’ve ticked off 10,000 steps for the day. Or, more to the point, a generation of social media addicts follow the lead of their favourite #fitspo influencers.
But just like the Insta glamours themselves, it’s important to examine more than just looks — because these fashionable accessories aren’t always 100% reliable.
The uni boffins tested the accuracy of the five devices’ step counts on people walking, jogging, and running on a treadmill, wearing the monitors on their left and right wrists as well as their waist.
Firstly, the good news: it doesn’t matter which wrist you wear your exercise watch on — left and right are as accurate as each other across all speeds.
But then, the bad news: devices worn on the waist are more accurate — in fact, some wrist-worn trackers slashed more than 10% from the step count, especially when walking at a slow pace.
The Fitbit One clipped on to the waist was the most accurate fitness tracker of the five, while the Jawbone UP24 performed best of the wrist-worn devices.
So even though you have to forfeit the wrist bling, and you might feel like you’ve got a clothes peg clipped to you when you go for a jog, it makes more sense to buy a waist-worn fitness tracker if you’re more concerned about accuracy than style.
“If you’re walking, and would like to wear one of the wrist-worn monitors, then the Jawbone may be the better option,” explains UNSW Exercise Physiologist Dr Belinda Parmenter.
“If running, there are more to choose from . . . the Fitbit One when worn on the waist was accurate across all speeds tested.
“Some people are using these devices because they’ve had a heart attack or they’ve been diagnosed with cardiovascular or another chronic disease where the health recommendations are to walk. These people are being very health conscious about their activity levels and want to know that what they are doing on a daily basis is not only enough, but also accurate.
“Most of these people are walking for exercise, and the interesting thing the study picked up was that some of the monitors weren’t as accurate at slower walking speeds. In fact, some undercounted steps by up to 12-13%.”
Dr Parmenter pointed out that these findings are only based on lab tests rather than everyday activity monitored by fitness trackers.