Objective: Most American adults fail to achieve recommended levels of physical activity and, as a result,are at elevated risk for many chronic diseases. Affective processes have been validated as targets forincreasing physical activity but are rarely targeted directly by behavioral interventions. This articledescribes 2 early phase studies used to develop HeartPhone, a smartphone application for conditioningassociations between physical activity and pleasure. HeartPhone exposes users to brief doses of evaluativeconditioning stimuli via background images on a smartphone lock screen. Method: Study 1evaluated the feasibility of delivering mobile evaluative conditioning and estimated doses received over7–21 days in a small sample of users (n = 6). Study 2 used a single-group prepost design to evaluate userexperience and determine whether any change in reflective motivation or physical activity was possibleover 8 weeks of HeartPhone use (n = 19). Results: In Study 1, users accumulated almost 2 min/day ofexposure to conditioning stimuli, indicating the feasibility of delivering microdoses of evaluativeconditioning via smartphone lock screens. In Study 2, adults reported accepting the application andconditioning stimuli, improved affective judgments of physical activity (enjoyment, intrinsic motivation,integrated regulations), and increased physical activity. Conclusions: These results provide proof-ofconceptfor a low-friction approach for enhancing affective processing and increasing physical activity.Based on early phase success as a tool for engaging smartphone users in behavior change, the HeartPhoneintervention is ready for a Phase IIb pilot and III efficacy trials.
All Science Journal Classification (ASJC) codes
- Applied Psychology
- Psychiatry and Mental health