eMOTION: Examining Affective Mechanisms in Physical Activity Engagement

Official title

Using Real-Time Data Capture to Examine Affective Mechanisms as Mediators of Physical Activity Adherence in Interventions

Overview

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.

Detailed 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.

Interventions

• Behavioral Physical 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 contex
• Behavioral TYPE/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
• Behavioral SAVOR enhancement
  SAVOR implements a brief savoring exercise on the smartphone that takes place either after the planned physical activity session or during the evening goal session (after the self-monitoring module). Participants will respond to questions that are intended to enhance and prolong positive experiences during physical activity. To trigger attentional deployment, a common savoring strategy that involves intensifying experiences by focusing on them, participants will answer three open-ended prompts.

Primary outcome measures

• Physical Activity: Step Count [Time frame: Daily total for weeks 1-19]
• Physical Activity: Minutes [Time frame: Daily total for weeks 1-19]

Secondary outcome measures (3)

• Affective Response [Time frame: Max 2 per 60-min physical activity period during weeks 2-9 and weeks 12-19]
• Affectively-Charged Motivations [Time frame: Up to once daily for weeks 2-9 and weeks 12-19]
• Anticipated Affect [Time frame: Up to once daily for weeks 2-9 and weeks 12-19]

Eligibility criteria

Inclusion criteria

• Aged ≥ 18 years
• Reside in the United States
• Self-reported BMI ≥ 25
• Current structured physical activity engagement < 60 minutes per week
• Own a personal smartphone device
• Reside in an area with Internet or Wi-Fi connectivity during the study period
• Able to speak and read in English
• Interested and willing to start a physical activity program
• 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 duration of the study period
• Able to read the small font on a smartwatch screen without glasses, or willing to carry reading glasses during physical activity for the purpose of reading the smartwatch screen

Exclusion criteria

• Inability to provide informed consent due to cognitive disability
• Inability to engage in one or more key treatment components, including those with medical conditions that preclude physical activity engagement or who cannot wear an accelerometer on the wrist or answer brief surveys on the smartwatch for any reason
• Current pregnancy
• Referred to the study by another participant or from Reddit.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Factorial

Masking

Triple blind

Primary purpose

Prevention

Study locations

United States · 1 center

• University of Southern California — Los Angeles

Publications

• Dunton GF, Hatzinger L, Crosley-Lyons R, Hewus M, Wang WL, Van Dyck D, Huh J. Randomized trial of a digital therapeutics intervention to enhance affective response during physical activity: Protocol for the eMOTION study. Contemp Clin Trials. 2025 Jul;154:107945. doi: 10.1016/j.cct.2025.107945. Epub 2025 May 12. PMID 40368026

Identifiers

NCT: NCT06570642 · UP-22-00332 · R01CA272933

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗