eMOTION: Examining Affective Mechanisms in Physical Activity Engagement

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 duration of the study period 10. 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: 1. Inability to provide informed consent due to cognitive disability 2. 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 3. Current pregnancy 4. Referred to the study by another participant or from Reddit.