BackgroundThe popularity of active video games (AVGs) has skyrocketed over the last decade. However, research suggests that the most popular AVGs, which rely on synchronous integration between players’ activity and game features, fail to promote physical activity outside of the game or for extended periods of engagement. This limitation has led researchers to consider AVGs that involve asynchronous integration of players’ ongoing physical activity with game features. Rather than build an AVG de novo, we selected an established sedentary video game uniquely well suited for the incorporation of asynchronous activity: online fantasy sports.ObjectiveThe primary aim of this study was to explore the feasibility of a new asynchronous AVG—active fantasy sports—designed to promote physical activity.MethodsWe conducted two pilot studies of an active fantasy sports game designed to promote physical activity. Participants wore a low cost triaxial accelerometer and participated in an online fantasy baseball (Study 1, n=9, 13-weeks) or fantasy basketball (Study 2, n=10, 17-weeks) league. Privileges within the game were made contingent on meeting weekly physical activity goals (eg, averaging 10,000 steps/day).ResultsAcross the two studies, the feasibility of integrating physical activity contingent features and privileges into online fantasy sports games was supported. Participants found the active fantasy sports game enjoyable, as or more enjoyable than traditional (sedentary) online fantasy sports (Study 1: t
8=4.43, P<.01; Study 2: t
9=2.09, P=.07). Participants in Study 1 increased their average steps/day, t
8=2.63, P<.05, while participants in Study 2 maintained (ie, did not change) their activity, t
9=1.57, P=.15). In postassessment interviews, social support within the game was cited as a key motivating factor for increasing physical activity.ConclusionsPreliminary evidence supports potential for the active fantasy sports system as a sustainable and scalable intervention for promoting adult physical activity.