BACKGROUND Top tier commercial physical activity apps rarely undergo peer-reviewed evaluation. Even fewer are assessed beyond six months, the theoretical threshold for behaviour maintenance. The purpose of this study was to examine whether a multi-component commercial app rewarding users with digital incentives for walking was associated with an increase in physical activity over one year. METHODS This 12-month quasi-experimental study was conducted in two Canadian provinces (n = 39,113 participants). Following a two-week baseline period, participants earned digital incentives ($0.04 CAD/day) every day they reached a personalized daily step goal. Mixed-effects models estimated changes in weekly mean daily step count between the baseline period and the last two recorded weeks. Models were fit for several engagement groups and separately by baseline physical activity status within engagement groups. RESULTS Nearly half of participants (43%) were categorized as physically inactive at baseline (fewer than 5000 daily steps), and 60% engaged with the app for at least six months ['Regular' (24-51 weeks of step data) or 'Committed' sub-groups (52 weeks)]. Weekly mean daily step count increased for physically inactive users regardless of engagement status (P < .0001). The increase was largest for 'Regular' and 'Committed' participants-1215 and 1821 steps/day, respectively. For physically active participants, step count increases were only observed in the 'Committed' sub-group (P < .0001). Effect sizes were modest-to-medium depending on the sub-group analyzed. CONCLUSIONS A commercial app providing small but immediate digital incentives for individualized goals was associated with an increased weekly mean daily step count on a population-scale over one year. This effect was more evident for physically inactive and more engaged participants.

中文翻译：

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在加拿大两个省，商业应用程序的使用与持续的体育锻炼有关：一项为期12个月的准实验研究。

背景技术顶级商业体育活动应用程序很少接受同行评审。六个月（行为维持的理论阈值）之后评估的数量甚至更少。这项研究的目的是研究一种多组件商业应用程序，该应用程序通过数字化的步行奖励措施奖励用户，是否与一年多的体力活动相关。方法这项为期12个月的准实验研究在加拿大两个省（n = 39,113名参与者）中进行。在为期两周的基准时间之后，参与者每天达到个性化的每日步骤目标，就可以获得数字奖励（每天0.04加元）。混合效果模型估计了基线期和记录的最后两个星期之间每周平均每日步数的变化。模型适用于多个参与小组，并分别根据参与小组内的基线身体活动状况进行拟合。结果将近一半的参与者（43％）被归类为在基线时身体不活跃（每天少于5000步），并且60％的用户使用该应用程序至少六个月[“常规”（24-51周的步数）或“委托”小组（52周）]。不活跃用户的每周平均每日步数增加，无论参与状态如何（P <.0001）。对于“常规”和“委托”参与者，每天分别增加1215和1821步，这是最大的增长。对于身体活动的参与者，步数增加仅在“投入”子组中观察到（P <.0001）。效果大小适中，具体取决于所分析的子组。结论商业应用程序为个体化目标提供少量但立即的数字激励，与一年中人口规模上每周平均每日步数增加有关。对于身体不活跃和参与度更高的参与者而言，这种影响更为明显。