Background:
Regular moderate to vigorous physical activity (PA) is essential for maintaining health and preventing the onset of chronic diseases. Both, global rates of smartphone ownership and the market for PA and fitness applications (apps) have grown rapidly in recent years. The use of PA and fitness apps may assist the general population in reaching evidence-based PA recommendations. However, it is unclear whether there are evidence-informed PA (EIPA) apps and whether behavior change techniques (BCTs) previously identified as effective for PA promotion are employed in these apps.
Objective:
The study aim was to identify English and German EIPA apps and employment of BCTs in those apps.
Methods:
Apps were identified in a systematic search using 25 predefined search terms in the Google Play Store. Two reviewers independently screened descriptions of apps and screenshots applying predefined inclusion and exclusion criteria. Apps were included if a.) their description contained information about PA promotion, b.) they were in English/German, c.) PA recommendations of the World Health Organization or the American College of Sport Medicine were mentioned, and d.) any kind of objective PA measurement was included. Two researchers downloaded and tested apps matching inclusion criteria for two weeks and coded their content using the Behavioral Change Technique Taxonomy v1 (BCTTv1).
Results:
The initial screening in the Google Play Store yielded 6,018 apps, 4,108 of which were not focused on PA or neither in German nor English. Descriptions of 1,216 apps were further screened for eligibility. Duplicate apps and light versions (n=694) and those with no objective measurement of PA, requiring additional equipment or not outlining any PA guideline in their description (n=1,184) were excluded. Of the remaining 32 apps, four were no longer available at the time of the download. Hence, 28 apps were downloaded and tested. Of these 28 apps, 14 did not contain any PA guideline as an app feature, despite having mentioning it in the description, five had technical problems, and three did not provide objective PA measurement. Thus, six were included in the final analyses. Of the 93 individual BCTs of the BCTTv1, on average, nine (SD: 5) were identified in these apps. Of the 16 hierarchical clusters, on average, five (SD: 3) were addressed. Only BCTs of the two hierarchical clusters ‘goals and planning’ and ‘feedback and monitoring’ were identified in all apps.
Conclusions:
Despite the availability of several thousand PA and fitness apps for Android platforms, very few addressed evidence-based PA guidelines and provided objective PA measurement. Further, available descriptions did not accurately reflect app content and only few EIPA apps incorporated several BCTs. Future apps should address evidence-based PA guidelines and a greater scope of BCTs to further increase their potential impact for PA promotion.