Researchers from the professorship Healthy Ageing, Allied Healthcare and Nursing (Hanze UAS) have found that walking speed influences the reliability and validity of a number of activity trackers. These results are presented by Fokkema et al. in their paper ‘Reliability and Validity of Ten Consumer Activity Trackers Depend on Walking Speed’ (2017) as published in Medicine & Science in Sports & Exercise.

Tryntsje Fokkema collaborated with Thea Kooiman, Wim P. Krijnen, Cees van der Schans and Martijn de Groot in order to ‘examine the test–retest reliability and validity of ten activity trackers for step counting at three different walking speeds.’ In extent, the researchers tried to shed light on the accuracy of wearables. ‘Thirty-one healthy participants walked twice on a treadmill for 30 min while wearing 10 activity trackers (Polar Loop, Garmin Vivosmart, Fitbit Charge HR, Apple Watch Sport, Pebble Smartwatch, Samsung Gear S, Misfit Flash, Jawbone Up Move, Flyfit, and Moves).’

The results show that accuracy is maximized for each brand at a different pace. ‘For the slow walking speed, the Garmin Vivosmart and Fitbit Charge HR showed the most accurate results. The Garmin Vivosmart and Apple Watch Sport demonstrated the best accuracy at an average walking speed. For vigorous walking, the Apple Watch Sport, Pebble Smartwatch, and Samsung Gear S exhibited the most accurate results.’ Finally, the researchers conclude that at an average and a vigorous walking speed consumer activity tracker performance is better than at a slower walking speed.

This research is the third in a series of studies into the validity and reliability of wearables by Quantified Self Institute. You can find the full paper on PubMed. Want to read a nice interview with one of the researchers from this study? SmartHealth published an extensive article (in Dutch) on its website. Interested in our previous validity studies? Then please consult our downloads page.