The Virtual Fitness Buddy Ecosystem: Using Digital Technology to Promote and Sustain Moderate-to-Vigorous Intensity Physical Activity in Children

Childhood obesity poses a critical public health concern and chronically remains as one of the strongest predictors of obesity as an adult. Scientific evidence has demonstrated that daily physical activity (PA) is imperative in preventing the onset of obesity. The outpour of academic and professional interest has increased the public awareness of the risks related to obesity (e.g., type 2 diabetes, cardiovascular diseases, cancers) as well as the importance of PA. However, studies show that the rising prevalence of childhood obesity has not faltered since 1999. Many existing PA interventions show short-term impact, but have failed to demonstrate longer-term efficacy in sustaining the changes in PA over time-a gap this project aims to address.

One important, yet commonly overlooked, limitation of existing PA interventions is the negative impact of extrinsic rewards, such as points, grades, and badges, which are often used in health promotion interventions to incentivize children for engaging with the program. Children become motivated to excel in obtaining the extrinsic rewards rather than learning the intrinsic benefits of the intervention. Consequently, these types of interventions have limited effects that may disappear altogether when they stop receiving extrinsic rewards. Another critical limitation of existing PA interventions related to the use of extrinsic rewards is that the focus on "beating the system" by obtaining extrinsic rewards decontextualizes the intervention from the child's everyday life. This is an isolating experience for the child, taking him or her away from existing social support (e.g., parents) and left to his or her devices to engage in PA, based solely on the motivation from extrinsic rewards.

Guided by the frameworks of social ecological theory and self-determination theory, we propose a paradigm-shifting intervention through an engaging, game-like platform that incorporates intrinsic reward systems by harnessing the power of technology to connect people and devices to promote PA in children. The Virtual Fitness Buddy (VFB) Ecosystem was designed to encourage children to embrace PA as a lifestyle change that can be sustained over time rather than a means to gain points. The Ecosystem meets this goal by leveraging one of the most influential existing social relationships in children's lives, the parent-child relationship. Using consumer-grade technological devices, such as mobile phones, the Ecosystem allows parents to stay involved in the intervention and support their children's PA efforts even when they cannot be with their children. In addition, a virtual pet, designed to mimic human-pet relationships in the physical world, will guide children to set and meet PA goals and offer tailored support.

Using technology to amplify the power of existing social relationships, children will learn to embrace PA as a lifestyle change while supported by their parents and the virtual pet within the Ecosystem. Because the intervention is embedded in the context of children's everyday lives, our preliminary findings demonstrated the potential of the Ecosystem to elicit high levels of engagement and excitement from both children and parents over a 3-day intervention period. The next critical question is whether the Ecosystem can maintain children and parents' engagement over longer periods of time, yielding sustainable changes in health behavior and lifestyle choices that were initiated by the Ecosystem.

In collaboration with YMCA, 480 children and 480 parents in 24 afterschool programs will be randomly assigned to treatment and control groups in a cluster-randomized controlled trial. Afterschool programs in the treatment group will receive the Ecosystem intervention for 3-months; afterschool programs in the control group will not experience the Ecosystem (but will receive the standard of care). All children will complete baseline assessments, a 3-month posttest, and a 6-month and 12-month follow up. Parents and children will provide self-report data on their perceived social support, motivation, and PA self-efficacy. PA will be assessed with activity monitors, which children will wear throughout the project.