Does Using Sports Trackers Improve Our Performance?
The Promise of Sports Tracking Devices
Since the introduction of heart rate monitors and GPS trackers on the market, these devices have become ever more accessible to amateur athletes. A survey from 2014[1] reveals that more than half of the participants of a half marathon used an app or sports watch for running. A recent qualitative study of runners’ experience with sports tracking technology[2] mentions motivation and decision support as expected benefits from these devices.
If sports trackers (and related software services for analysis of their data) live up to these promises, we would expect to see a sustainable improvement in performance for athletes using them, especially among performance-oriented athletes. Let’s investigate if this is true for the current beta test users of Fithaxx.
Sustainable Performance Improvement
What does it mean to have a sustainable improvement in performance? This analysis uses the performance measure as defined before in [3]. In practice, this means that for every activity there is a measure of average speed, controlled for various levels of effort expressed as heart rate zones relative to an athlete’s maximum. As explained in [3], these measurements are only collected for fragments of activities that have a more-or-less steady state heart rate. The chart below shows this performance metric for a single example user (guess who?), plotted over time, for the year 2017:
Every year has such a peak performance per heart rate zone (given that there was reliable performance data for that zone), and in this context, a “sustainable improvement” of performance means that the multi-year trend of peak performances must be upward. This approach prevents counting short-term gains (potentially followed by long-term injuries) as “improvement.”
Data Collection and Selection
The Fithaxx service collects historical activity data by consent of every individual user, through application programmer interfaces (API) of 3rd parties. This data contains per-second measurements of attributes such as speed, heart rate, or elevation. This analysis uses data from users that have running activities with heart rate — and speed measurements, for at least one heart rate zone, for at least two years, the latter for establishing long-term progress. These criteria led to a selection of 12,523 runs from 51 athletes.
Computing Progress of the Population
The chart above shows how to establish peak performances per heart rate zone per year for a single runner. For every athlete and heart rate zone, a simple linear model expresses the trend over time for these peak performances:
The above shows the progress over time for heart rate zone 3 for the same athlete used in the previous example. This athlete’s performance improved roughly 0.35 km/h per year in zone 3.
The next step is to combine all these individual zone improvement trends to get a population overview for a given zone:
Now that we collected all individual progress trends per heart rate zone, we can establish summary statistics per zone, and perform significance tests to compare the results with the null hypothesis that the mean improvement is 0:
So Did We Runners Get Any Better?
For every heart rate zone, we can see an average improvement. However, for zones 2–5 these improvements are not significant or barely significant. Moreover, we see that for roughly half of the population, their performance gains are negligible or even in decline.
It looks like the potential benefits of sports activity trackers are underutilized by a significant portion of the running test users of Fithaxx. This gap indicates room for improvement in motivational -and decision support aspects of existing and new devices and applications for training assistance.
Want To Learn More About Your Improvement?
If you are an athlete and are using Strava to record your activities, please consider signing up at fithaxx.com!
With XX from Fithaxx
Notes
[1] Janssen M, Scheerder J, Thibaut E, Brombacher A, Vos S (2017) Who uses running apps and sports watches? Determinants and consumer profiles of event runners’ usage of running-related smartphone applications and sports watches. PLoS ONE 12(7): e0181167. https://doi.org/10.1371/journal.pone.0181167
[2] Armağan Kuru (2016): Exploring Experience of Runners with Sports Tracking Technology, International Journal of Human-Computer Interaction, DOI: 10.1080/10447318.2016.1202461
[3]:
