Mobile Supportive Teams for Reinforcing Increased Daily Exercise Study

The goal of this research is to examine the addition of a digitally delivered social support training approach to an existing digital program designed to promote a physically active lifestyle among self-selected teams of adults who are not meeting physical activity guidelines. The main aims are to:

1. Determine if the social support training intervention promotes significantly greater changes in moderate-to-vigorous intensity aerobic physical activity (such as a brisk walk) as measured by an accelerometer (research grade physical activity measurement device) at 3 months compared to the same intervention without social support training among self-selected teams of adults who are not meeting the physical activity guidelines.
2. Determine if the social support training intervention promotes significantly greater changes in social support, motivation, accountability, and autonomy social support (free from excessive control and encouraging one's free will) at 3 months and 12 months compared to the same intervention without social support training.
3. Determine if the social support training intervention promotes significantly greater changes in moderate-to-vigorous intensity aerobic physical activity as measured by an accelerometer at 12 months compared to the same intervention without social support training.
4. Explore whether social support mediates increased and sustained moderate-to-vigorous intensity aerobic physical activity among the entire sample of participants.

Self-selected teams of 3-8 insufficiently active adults (about 60 teams comprised of a total of 300 participants) will be randomized to receive either a 3-month, theory-based, technology-delivered physical activity intervention characterized by personalized physical activity goals, a wearable physical activity tracker, electronic feedback, and behavior change modules embedded within a mobile-compatible app (Team) or the same intervention plus digitally delivered social support training (Team+Training). Outcome assessments will be completed at baseline, 3, and 12 months.

Eligibility Criteria:
Inclusion Criteria:

Participants must:

* be at least 18 years of age
* be insufficiently physically active (\< 150 minutes per week of moderate-intensity equivalent aerobic physical activity as measured by waist-worn accelerometer (research grade physical activity measurement device) - i.e., sum of time spent in minutes of moderate-intensity activity plus twice the minutes spent in vigorous-intensity activity \< 150 minutes per week)
* be part of a self-selected team of 3-8 individuals each of whom also meet all other eligibility criteria (members of the same household are only eligible to participate if they are on the same team - limit one team per household)
* have access to a smartphone (Android or iphone operating system-based) with an internet connection
* report being able to walk at least ¼ mile without stopping
* be able to provide informed consent
* complete all screening and baseline questionnaires and activities

Exclusion Criteria:

* participating in another physical activity study or program
* are pregnant, breastfeeding, less than 6 months post-partum, or plan to become pregnant during the time frame of the investigation
* report a medical condition that would affect the safety and/or efficacy of a physical activity program (e.g., terminal illness; uncontrolled heart condition, dementia, bulimia nervosa or binge eating disorder, other significant psychiatric problems, or use of insulin)
* report conditions that in the judgment of the Principal Investigator would render them unlikely to be able to independently follow the intervention protocol for 3 months, including conditions which might compromise their ability to engage independently with the intervention website materials and wearable physical activity tracker, as well as complete online questionnaires and adhere to wearing an accelerometer