Exploring Longitudinal Use of Activity Trackers

Networked activity trackers have become an important tool for assessing physical activity, as part of behavior change interventions, within epidemiological studies, or driven by personal interest. However the use of activity trackers is often abandoned after a few months, and their effect on health behavior is unclear. We conducted a longitudinal study observing the use of activity trackers by 34 patients recovering from a myocardial infarction. The patients used the tracker continuously for up to more than one year. We observe two usage patterns: Regular use on some but not all days per week is observed for all patients and remains consistent during the usage period. Uninterrupted use on many successive days is observed for some patients only, happens only once per patient, and mostly at the beginning of the use. We hypothesize that the activity tracker is particularly used as a motivational tool by objectively measuring one's physical activity, and only some people use it as a tool for learning one's behavior.