Table 1 Integration of theoretical concepts and intervention procedures

Social Functions

Educational materials

• Encouragement/prompt

-Receive same PA prescription.

-Receive walking “tips of the week” once weekly.

Social Functions

Shape walking quantity and speed

• Modeling

-Receive one-on-one in-person meeting. Program activities demonstrated and practiced with corrective feedback.

• Resources/assistance

-Given pedometer, stopwatch, walking log, and program manual.

• Behavioral monitoring

-Prompted once weekly to submit walking logs to research staff.

-Self-monitor walking quantity and speed using walking log, pedometer, and stopwatch.

• Behavioral norms

-Walking quantity and speed compared to other program participants and past performance.

• Behavioral refinement

-Given tailored weekly goals and graphical feedback to increase walking quantity and speed.

• Encouragement, praise

Environment and Social Structure and Functions

Online WalkLink social network site

• Setting/resource access/proximity, number, homogeneity

-Promoted as a local program and participants informed they were living in same neighborhood as other participants.

• Network physical proximity

-Prompted to attend four “meet the group” walks led by project staff in central neighborhood locations; participants asked to introduce themselves/talk to each participant.

• Virtual and in-person interaction modes

-Access to WalkLink Facebook site during, and at least 1 year after program. Site activities include: posting profile, inviting family/friends/coworkers to join site, posting and joining local walking and PA events,discussion board, status updates, posting photos, “friending” other participants; received emails from site.

• Network centrality and transitivity

• Modeling/norms

• Encouragement, praise

• Resources, assistance, companionship

-Eligible for entry into drawings for gift cards contingent on posting or joining walking/activity events on WalkLink site.

• Behavioral monitoring

Environment and Social Structure and Functions

Shape social network-building activities across in-person settings and online WalkLink site

• Behavioral monitoring

-Self-monitor number of walks taken with others, and in-person community-based and Facebook-based social networking activities completed each week using checklist (Figure 3); submit networking activities once weekly to research staff.

• Setting/resource number, homogeneity

• Virtual and in-person interaction modes

• Network centrality and transitivity

• Behavioral norms

-Participation in social networking activities compared to other program participants and past performance.

• Behavioral refinement

-Given tailored weekly goals and graphical feedback to increase social networking activities.

• Encouragement, praise