Using Real-Time Data Capture to Examine Affective Mechanisms as Mediators of Physical Activity Adherence in Interventions
University of Southern California
Summary
This early-phase trial will test intervention strategies to influence affective mechanisms underlying physical activity and determine whether changes in those mechanisms result in change in physical activity behavior among inactive adults who are overweight or obese.
Description
This ORBIT model phase 1 trial will examine whether affective mechanisms (1) can be experimentally manipulated in real-world settings; and (2) mediate the relationship between interventions and physical activity behavior. A novel physical activity intervention will be optimized by efficiently disentangling the effects of its core component and two enhancement components on affective mechanisms associated with physical activity engagement.
Eligibility
- Age range
- 18+ years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion criteria: 1. Aged ≥ 18 years 2. Reside in the United States 3. Self-reported BMI ≥ 25 4. Current structured physical activity engagement \< 60 minutes per week 5. Own a personal smartphone device 6. Reside in an area with Internet or Wi-Fi connectivity during the study period 7. Able to speak and read in English 8. Interested and willing to start a physical activity program 9. Willing to wear a Fitbit Versa smartwatch provided by the study team everyday continuously (including at work and during physical activity), in place of any Fitbits or smartwatches previously worn, for the dur…
Interventions
- BehavioralPhysical Activity Goals mHealth Intervention
On days participants plan to exercise, they engage in two daily goal sessions (morning and evening). Morning sessions provide an activity goal for the day and ask the participant to create a plan, anticipate barriers, and brainstorm solutions for achieving this goal. The affect-based goal condition asks participants to engage in either (1) a type (50% of daily goals) or (2) a context (50% of daily goals) of physical activity that allows them to experience positive affect. Goals focused on context are randomly generated to suggest that the participant performs activity (1) in a place; (2) in a social situation; or (3) while listening to something that makes them feel good. The intensity-based goal condition asks participants to maintain a certain target heart rate range during physical activity. Starting heart rate reflects the approximate age-adjusted heart rate max, with goals progressively increasing from 55% to 70% heart rate max.
- BehavioralTYPE/CONTEXT enhancement
TYPE/CONTEXT augments intervention effects by providing tailored recommendations for activity types and contexts that satisfy personally-important psychological needs as rated by each participant at baseline. Ratings from a crowdsourced panel of adults on Amazon Mechanical Turk will be used to determine the potential for specific activity types and contexts to satisfy psychological needs; our tailoring algorithm will then recommend the corresponding activity type or context while accounting for reported constraints (e.g., ability, access). These details will be incorporated into a tailored recommendation provided to participants each Sunday as they make activity plans for the upcoming week. Specifically, the program will randomly select either type or context (i.e., location, audio, social) recommendations and will rotate every two weeks. For TYPE, participants' top 3 activity types are recommended; for CONTEXT, participants' top 3 activity contexts are recommended.
- Behavioral
Location
- University of Southern CaliforniaLos Angeles, California