Development of an Accelerometer-Linked Online Intervention System to Promote Physical Activity in Adolescents

May Development of an Accelerometer-Linked Online Intervention System to Promote Physical Activity in Adolescents Nicole Guthrie 0 1 Andrew Bradlyn 0 1 Sharon K. Thompson 0 1 Sophia Yen 0 1 Jana Haritatos 0 1 Fred Dillon 0 1 Steve W. Cole 0 1 0 1 HopeLab Foundation, Redwood City, California, United States of America, 2 West Virginia University , Morgantown , West Virginia, United States of America, 3 Santech Inc., La Jolla, California, United States of America, 4 Department of Pediatrics, Division of Adolescent Medicine, Stanford Medical School , Stanford, California , United States of America 1 Academic Editor: Marc A Adams, Arizona State University , UNITED STATES Most adolescents do not achieve the recommended levels of moderate-to-vigorous physical activity (MVPA), placing them at increased risk for a diverse array of chronic diseases in adulthood. There is a great need for scalable and effective interventions that can increase MVPA in adolescents. Here we report the results of a measurement validation study and a preliminary proof-of-concept experiment testing the impact of Zamzee, an accelerometerlinked online intervention system that combines proximal performance feedback and incentive motivation features to promote MVPA. In a calibration study that parametrically varied levels of physical activity in 31 12-14 year-old children, the Zamzee activity meter was shown to provide a valid measure of MVPA (sensitivity in detecting MVPA = 85.9%, specificity = 97.5%, and r = .94 correspondence with the benchmark RT3 accelerometer system; all p < .0001). In a subsequent randomized controlled multi-site experiment involving 182 middle school-aged children assessed for MVPA over 6 wks, intent-to-treat analyses found that those who received access to the Zamzee intervention had average MVPA levels 54% greater than those of a passive control group (p < 0.0001) and 68% greater than those of an active control group that received access to a commercially available active videogame (p < .0001). Zamzee's effects on MVPA did not diminish significantly over the course of the 6-wk study period, and were statistically significant in both females and males, and in normal- vs. high-BMI subgroups. These results provide promising initial indications that combining the Zamzee activity meter with online proximal performance feedback and incentive motivation features can positively impact MVPA levels in adolescents. - Funding: The research reported here was supported by the nonprofit HopeLab Foundation. HopeLab develops behavioral interventions to improve health in young people. The design, conduct, analysis, and reporting of this study represents a scientific collaboration between HopeLab and Drs. Bradlyn, Yen, and Thompson. Nicole Guthrie, Jana Haritatos, Fred Dillon, and Steve Cole are employed by HopeLab Foundation, which funded this research, had a role in study design, data collection and analysis, decision to publish, and preparation of the manuscript. None of the authors have any financial or Sub-optimal physical activity in youth has been identified as a major public health challenge [13]. Recent estimates indicate that only 68% of U.S. adolescents achieve the CDCother conflicting interest in the scientific results of this study. Santech Inc. provided support in the form of a salary for author SKT, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific role of this author is articulated in the author contributions section. Competing Interests: The authors have read the journal's policy and have the following conflicts: The Zamzee intervention system studied in this research was developed by the nonprofit HopeLab Foundation. Nicole Guthrie, Jana Haritatos, Fred Dillon, and Steve Cole are employed by HopeLab Foundation. HopeLab develops behavioral interventions to improve health in young people. The design, conduct, analysis, and reporting of the intervention pilot study represents a scientific collaboration between HopeLab and Drs. Bradlyn, Yen, and Thompson. At the time of this research, Dr. Thompson was an employee of Santech Inc., which also develops behavioral interventions to improve health. Santech has no financial, intellectual property, or other interests in the Zamzee intervention system. This does not alter the authors' adherence to PLOS ONE policies on sharing data and materials. recommended 60 min of moderate to vigorous physical activity (MVPA) per day [4]. U.S. childrens MVPA levels decline with age, showing a particularly steep drop during middle school years [5,6]. Given the association between low MVPA in adolescents and subsequent low MVPA in adulthood [79] and associated elevations in risk for a diverse array of adult chronic illnesses [1012], there is a great need for effective and efficiently scalable interventions to increase MVPA in middle-school aged children. Existing interventions to increase physical activity in adolescents range from curriculumbased programs to the use of active video games (i.e., games in which physical movement is part of the gameplay mechanism). Recent literature reviews suggest that no current intervention strategies have been able to consistently induce the sustained changes in MVPA needed to have health benefits in general population samples [13]. However, there is considerable interest in the possibility of improving the physical activity impact of active videogames due to their intrinsic appeal [14], relative ease of distribution, and the potential for such interactive technologies to engage basic positive motivational processes [15,16] that have been identified as key drivers of sustained behavior change [17,18]. Small fixed and intermittent incentives in particular have been shown to promote positive health behaviors in adults [19,20] and may warrant further investigation in the context of adolescent physical activity. In addition, proximal feedback regarding physical activity levels has also been shown to enhance motivation [21,22] and promote sustained behavior change [23,24]. In the present studies, we evaluated a new metrics-driven incentive motivation program called Zamzee which seeks to increase MVPA in adolescents by combining proximal feedback on physical activity levels with frequent small scale incentives [25,26]. These two basic principles of behavior change were implemented through the combination of a small wearable 3-axis accelerometer system to assess MVPA (the Zamzee activity meter) and an online feedback and rewards program that seeks to harness basic principles of incentive motivation and intrinsic motivation [17,27]. To maximize efficiency and scaling potential, both components were engineered to be autonomous of program administration staff and as inexpensive as possible while providing accurate MVPA measurement and minimal sufficient external incentives to enhance MVPA over time. This report presen (...truncated)