Social Incentives To Encourage Physical Activity and Understand Predictors

This is a four-arm randomized, controlled trial with a 24-week intervention period and
12-week follow-up period. Participants are considered ready to be randomized once they have
completed all surveys, established a baseline step count, and selected a step goal
increase.Participants in the control arm will receive no other interventions during the
24-week intervention period or the 12-week follow-up period. Participants randomized to the
one of the three intervention arms will have a 4-week ramp up towards their step goal. The
participant will then be asked to maintain their goal during the 20-week "maintenance period"
and the 12-week "follow-up period." Participants in arms 2-4 will be entered into an
intervention approach that has points and levels designed to incorporate insights from
behavioral economics. Participants in the supportive social incentive arm will be asked to
identify a family member or friend to be their support sponsor. This sponsor will be
encouraged to support the participant in their progress during the study. Participants in the
competitive social incentive arm will be in a group of three total participants.At the end of
each week the participants will receive notification that ranks them on their cumulative
points in the study thus far and also displays their level.This feedback may help to induce
participants to compete for the top spot among the group. Participants in the collaborative
social incentive arm will be in a group of three total participants as a team. Each day one
of the members of the group will be randomly selected to represent their team for that day.
In this design, each person is accountable to the others on the team and this may induce a
collaborative effort to meet their daily goals.

Inclusion Criteria:

1. Age 18 years or older;

2. ability to read and provide informed consent to participate in the study;

3. Self-reported body mass index (BMI) of 25 or greater.

4. Smartphone or tablet compatible with application for the wearable activity tracking
device.

Exclusion Criteria:

1. Conditions that would make participation infeasible such as inability to provide
informed consent, illiteracy or inability to speak, read, and write English;

2. conditions that would make participation unsafe such as pregnancy or being told by a
physician not to exercise;

3. already enrolled in another study targeting physical activity;

4. any other medical conditions or reasons he or she is unable to participate in a
physical activity study for 36 weeks.