When it comes to technological advancements in the world of health and fitness, wearable trackers such as the Fitbit, Apple Watch, PulseOn, and Samsung Gear are considered to be the frontrunners.
Over the past several years, more individuals have relied on these devices to gauge the progress they are making in their fitness journeys — from heart rate and pulse to calories burned and their personal metabolism rate. Additionally, users have been gathering this data and bringing it to their primary physicians, only to discover that they cannot use the data.
Such a response has led experts to questions just how accurate these fitness trackers are — or are not.
In a study conducted by Stanford University’s Mobilize Center, the minute-by-minute activities of over 700,000 fitness tracker users were analyzed in order to shed light on how activity levels, age, gender, and location impact their weight and overall fitness.
At first glance, it would appear that the information is correlated to one’s assumptions: those who take more steps in a day are more fit, as opposed to those who take fewer steps. This phenomenon was dubbed an “activity inequality” by researchers.
Countries with a higher rate of activity inequality are, to name a few, the United States, Saudi Arabia, Brazil, Canada, and Australia. However, two factors seem to contribute this supposed inequality: the region in which users live, as well as the device they are using.
In the second part of this study, Mobilize Center researchers put several brands of fitness trackers to the test in order to discover their accuracy. Amongst the subjects were the newest version of the Apple Watch, Basis Peak, Fitbit Surge, Microsoft Band, Mio Alpha 2, PulseOn, and Samsung Gear S2.
Throughout the course of the study, the 60 participants would wear upwards of four fitness trackers at a time while performing physical activities — running on a treadmill, riding a stationary bike, and so on — in hopes of gathering heart rate and energy output data.
According to the findings, each device’s heart rate tracking was remarkably accurate, with less than 8 percent deviation. Admittedly, the Stanford researchers were somewhat shocked by these results, as they had originally anticipated a poorer performance.
In spite of these positive results, they did not get their hopes up when it came time to analyze output tracking — a wise move on their end.
Unfortunately, the most accurate device was still 30 percent off when compared to the gold standard measuring instrument, while the most inaccurate was a staggering 93 percent off.
Despite these negative findings, it is important to note that no device is ever going to be flawless. Each is going to come with its own inaccuracies and shortcomings. Therefore, it would be best to encourage users to compare and contrast the data their devices have gathered with the data their doctors provide — that way, tracking their health and fitness is more finite than a guessing game.