Using Technology to Investigate Dietary and Physical Activity Lapses in a Behavioral Weight Loss Program

Approximately 70% of American adults have overweight/obesity, which increases risk of major medical issues and preventable death (Abdelaal et. al, 2017). Many individuals with overweight/obesity attempt to lose weight through behavioral strategies, e.g., adopting a reduced-calorie diet and/or increased physical activity. However, it is exceedingly difficult to consistently adhere to a reduced-calorie diet and high levels of physical activity; as such, most individuals attempting to lose weight via these methods experience repeated instances of non-adherence, i.e., dietary and physical activity lapses. These lapses are a core driver of weight loss failure, undermining individuals' ability to achieve weight control (Forman et al, 2017). As such, it is important to understand what predicts these lapses, which in turn allows for better lapse prevention. The current study proposes to measure these risk factors in an ecologically valid manner, i.e., in the moment they occur and in the context of individuals' everyday lives, using advanced technology. Specifically, the current study will use ecological momentary assessments (EMA; brief, repeated surveys delivered in one's natural environment, typically via a smartphone) and sensor technology (e.g., Fitbit and sensors on smartphone devices) to measure momentary risk factors of dietary and physical activity lapse, as well as the lapses themselves. Findings from this research project will lay the groundwork for a sophisticated just-in-time adaptive intervention (JITAI), a tailored, personalized intervention that targets momentary risk factors (e.g., cravings) via in-the-moment support, thereby reducing lapse occurrence and improving adherence to behavioral weight control prescriptions.