One of the fastest growing areas in consumer tech, wearable fitness or activity trackers have captured the public imagination with growing levels of interest and adoption.
We have put together some brief updates from recent research conducted on or using these trackers.
What are Fitness Trackers?
Basically, fitness trackers are a collection of wearable sensors, with the most basic trackers having an accelerometer that measures motion. More sophisticated trackers that have optical sensors for heart rate measurements and GPS receivers for real time geolocation and distance tracking are also available.
There are trackers for all different sensibilities and purchasing powers, from the very minimalist , to the rugged adventurous user (1) and even luxurious hand-crafted timepieces for the traditionalist (2).
How do they work?
Most trackers just measure and store acceleration or motion using an accelerometer. The actual metrics like “number of steps”, “distance travelled”, “calories burned” or “sleep statistics” are derived through back-end algorithmic calculations, often handled on a paired device, usually a smartphone or computer that syncs with the tracker.
Are they accurate at activity tracking?
In short, most trackers are not very accurate in the metrics they claim to measure (3), although the degree of inaccuracy does vary amongst manufacturers (4). However, as pointed out by recent studies (5), the success of trackers is not dependent on the accuracy of their measurements, but more on their ability to engage the user, provide feedback on activities and overall as motivation tools to help the user to become more physically active (6).
Which are the groups where trackers are making a difference?
Generally, any moderate increase in physical activity has been linked to lowering risk of cardiovascular disease with 10,000 steps a day often being touted as a health goal for the average adult. Moreover, from helping older adults with chronic illness (7) to pediatric cancer patients striving to avoid chemotherapy related fatigue (8), fitness trackers meant for average consumer use are being deployed in increasingly challenging applications, which should help drive the improvement of trackers.
What are some take home messages if you’re using trackers or considering buying one?
For most users, ease-of-use of the device or the accompanying smartphone app goes a long way towards real-world use (9). Additionally, an active social platform for community support and sharing (10) or encouraging healthy competition and gamification (11) can greatly add to the end user experience (12).
Most fitness trackers do not disclose the type and accuracy of enclosed sensors. Also, for serious medical conditions, use of fitness trackers without professional supervision is discouraged, as in case of sleep disorders (13).
The lifecycle of most trackers is starting to mirror that of smartphones, so you can expect a good amount of usage for at least 2 years. However, improvements in the firmware or the accompanying app can add exponentially to the utility of the trackers. Usually, these include improved data presentation, notification or in some cases upgrade the back-end calculations that can increase reliability and have major impact on actual tracker use (14).
How fitness trackers are benefitting data scientists?
Based on the exploding numbers of fitness tracker sales, it is safe to say that the availability of always-on health data from millions of users is truly groundbreaking. This is likely to mirror the tremendous value that social media companies have built from user-generated data (15). For the fitness data industry, this means innovations in algorithms than can run on lean wearable hardware, and building robust back-end applications to utilize these ever increasing quantity and diversity of health data points in standardized frameworks to gain healthcare insights (16).
What are some of the main challenges moving forward?
In one word: Privacy.
As a recent study has revealed, many fitness trackers are susceptible to Bluetooth surveillance, insecure data transmission and data manipulation (17). Moreover, depending on the country, the laws governing data generated by fitness trackers are less stringent on privacy violations when compared to traditional healthcare data. Unless these issues are addressed by both fitness tracker manufacturers and governments with transparency, there may be a significant dent in consumer confidence regarding wearable technologies (18).
By Mukundh Balasubramanian, PhD