We conducted this study in a suburban community in North Carolina from March through October 2005. In September and October 2004, nine local church pastors participated in in-depth interviews and provided input on the design, development, and implementation strategies for health promotion programs in churches in general and a faith-based PA program specifically. Pastors were recruited from a list of pastors who attended (or sent a representative to) at least one of two luncheons held for ministers in the local community to determine potential strategies for health promotion and disease prevention among blacks.

Data from in-depth interviews suggested that, in general, health was viewed as a concept that encompassed spiritual, physical, mental, and emotional health. Pastors indicated that they play a role in the health of their church congregants by setting an example for healthy living, imparting the knowledge that wholeness and health are essential parts of Christian character that enable one to do God's bidding and that the body is God's temple. They advocate, encourage, and support efforts to engage in healthy behaviors and to implement health-related programming within the church. Pastors provided suggestions for why their congregants were not physically active (e.g., lack of motivation, knowledge, time, or resources) as well as feedback on ways to successfully implement a faith-based intervention (e.g., getting buy-in and support from the pastor, making sure to offer sessions during times that do not conflict with other church activities, linking health-promoting activities to church ministries rather than creating separate programs).

We used information from the in-depth interviews to shape the study design and session content of the faith-based PA intervention. Because the pilot study was designed to determine the feasibility and acceptability of the intervention strategy, a preintervention and postintervention study design with no control group was used. This design was deemed the most acceptable for church pastors and is in line with previous research suggesting that a no- or low-attention control would not be well received by this population (22). The intervention, which was based on social cognitive theory (23,24), included eight weekly group sessions focusing on behavioral strategies to increase daily MPA and VPA. Weekly sessions included 30 minutes of MPA and a 60-minute discussion session (Table 1). Sessions opened and closed with prayer, and session content was presented from a theological perspective with a focus on personal health care as a method of protecting God's temple. Session five focused entirely on healthful living and negotiating barriers from a Biblical perspective. Participants discussed scriptural references that supported the notion of self-care and negotiating barriers, which were used throughout the remaining sessions. Incentive items were provided at each session to encourage PA participation. A certified fitness instructor conducted the 30-minute MPA session and provided an opportunity for participants to practice using incentive items. Incentives were culturally relevant items such as faith-based aerobics videos, a gospel exercise CD, a tote bag, and a T-shirt with a faith-based slogan that fit the intervention theme.

Participants maintained weekly logs of pedometer step counts, which were used to self-monitor walking, and received a weekly summary to track walking progress throughout the study. We used incentives to encourage participants to increase their daily MPA to at least 30 minutes by engaging in moderate-intensity walking. Although participants were not given specific targets to increase their steps per day, they were advised of the 10,000 steps recommendation for daily walking (25) and were told that striving to reach this goal was in line with achieving the recommendation for MPA.

We hired group leaders to lead the weekly intervention sessions at churches. The following characteristics were considered desirable for group leaders: 1) having a working knowledge of general health and wellness but not being currently employed as a health educator, 2) being physically active but not exceptionally athletic, 3) having previous experience working with blacks and other groups in faith-based settings, 4) being comfortable speaking in group settings; and 5) not being a member of a church involved in the intervention. These criteria were selected to avoid hiring highly trained individuals, which might hamper the ability to disseminate this type of intervention to a larger audience, and to avoid potential biases by hiring church members because all four churches could not be represented in group leadership. Two black females were recruited as group leaders. Each group leader was assigned to lead sessions at two churches, depending on the time the church selected to hold the sessions and the availability of the group leader.

Each church pastor also selected one church member to serve as a liaison between the church and the study staff and to attend to any church-related logistical issues. We paid church liaisons a modest honorarium for their participation in the study. In addition, church liaisons received a group leader training manual and session materials to facilitate continued implementation of the PA program after completion of the study. No additional incentives or compensation were provided to churches or pastors.

We selected a convenience sample of four churches that identified themselves as predominantly serving blacks and whose pastors participated in one of the previously mentioned ministers’ luncheons. Recruitment for study participants was at the churches’ discretion; it primarily consisted of making announcements during Sunday morning worship services and weekly activities and placing flyers throughout the church and in the Sunday bulletin. Interested individuals were invited to attend a general-interest session held at each church and led by the study’s principal investigator (MCW). Interest sessions were held during the time the church had selected for the weekly intervention sessions. This limited the number of individuals who would be unable to attend the sessions regularly. During the interest session, the principal investigator explained the study procedures and eligibility criteria and answered participant questions. At the end of the interest session, participants were screened for study eligibility using the following criteria: 1) being self-identified as black; 2) being 18 years of age or older; 3) not currently meeting recommendations for MPA or VPA (defined as self-report of 30 minutes or less of MPA on 5 or fewer days per week; 20 minutes or less of VPA on 3 or fewer days per week, or obtaining recommended MPA and VPA, but in bouts lasting less than 10 minutes, as assessed using a modified version of the International Physical Activity Questionnaire); 4) responding “no” to all questions on the Physical Activity Readiness Questionnaire (PAR-Q) or having obtained medical clearance; 5) having no other physical illnesses or disabilities limiting PA; and 6) being willing to commit to participating in weekly intervention sessions and all data collection visits. All individuals who attended an interest session received a pedometer, regardless of their eligibility for study participation. Eighty-seven participants met the eligibility criteria and were enrolled in the study.

All study procedures were approved by the Institutional Review Board at Wake Forest University Health Sciences. Eligible participants provided written informed consent before participating in data collection or in the study intervention.

Intervention fidelity, which is "the degree to which a program is implemented as intended by its developers," (25) was addressed by several methods. Training materials were developed and used to standardize program delivery across group leaders. Group leaders participated in a mandatory half-day training session that provided an overview of the study goals, objectives, and content. Before each intervention session, group leaders received a scripted discussion guide for each session and handouts for study participants. Group leaders also met for about 2 hours with the principal investigator before each session to review and discuss session content and have any questions answered. During the meetings, the principal investigator modeled delivery of the session content and provided opportunities for the group leaders to provide input, ask questions, and practice delivering the intervention content. Intervention fidelity was also monitored by anonymous evaluation forms that participants completed at the end of each session and by examining weekly records of participant attendance and pedometer logs.

All measurements were collected at baseline and after 3 months except for records of daily walking, which were collected weekly throughout the study. All measurements were taken at the church where participants were recruited unless otherwise requested, and all measurements were taken by the same trained data collectors.

Physical Activity Readiness Questionnaire. The PAR-Q, which is a valid screening tool for pre-participation in PA (27-30), was used to screen study participants. The PAR-Q includes seven questions that assess the presence or absence of several known risk factors that preclude participation in MPA or VPA without consent from a medical professional. Participants who answered "yes" to any question on the PAR-Q were required to obtain medical clearance from a health care provider before being enrolled in the study.

Daily walking. Daily walking was measured throughout the study using an Accusplit Eagle pedometer. Previous studies have demonstrated the feasibility of the pedometer as an objective measure of PA and as a potential motivator to increase PA levels (31,32). All participants received a pedometer and instructions for wearing the pedometer and recording daily walking. Group leaders instructed participants to wear the pedometer on the waistband, in line with the outside of the knee cap, during all waking hours unless the participant was immersed in water. Participants were instructed to clear the pedometer count each morning and to record the total number of steps taken at the end of each day using a log sheet. The log sheets included space to record the time the monitor was put on in the morning, the time it was removed at the end of the day, the day and date of recording, and the total number of steps taken for the day. Log sheets were provided each week for recording the number of daily steps, and participants submitted the log sheets weekly for feedback on walking progress.

Baseline number of steps per day were based on the average number of steps per day during week 0. Data for week 4 were based on the average number of steps per day during weeks 1 to 4, and data for week 12 were based on the average steps per day during weeks 5 to 12. We performed separate analyses using only data collected for weeks 4 and 12. Results were comparable with data based on average number of steps per day across weeks (data not shown); thus, to maximize the sample size available for data analysis, we used the average number of steps per day across weeks. In addition, we analyzed steps per day categorically: less than 5000 steps per day (sedentary); 5000 to 7499 (low active); 7500 to 9999 (somewhat active), 10,000 to 12,499 (active), and 12,500 or more (highly active) (33).

Moderate- and vigorous-intensity physical activity. Self-reported participation by minutes per week in MPA, VPA, and walking was assessed using a modified version of the International Physical Activity Questionnaire (IPAQ) (34). The IPAQ assesses adherence to national recommendations for MPA and VPA during the previous 7 days. Two questions assess days per week and time per session for VPA or MPA lasting 10 minutes or more per session. Three questions assess daily and brisk walking at work, at home, for transportation, and for recreation, sport, exercise, or leisure for 10 minutes or more per session. To increase the accuracy of self-reported data, we modified the questions by changing open-ended questions related to frequency to closed-ended questions. Participants selected days per week from a list ranging from 0 days to 7 days. We also modified the questions on duration of PA from an open-ended response to categorical responses to try to reduce overestimation: "I do not do _____ activity for more than 10 minutes in a row"; "10 to 15 minutes"; "15 to 30 minutes"; "30 to 45 minutes"; "45 to 60 minutes"; and "Over 60 minutes." To calculate a continuous measure of PA participation, 0, 10, 15, 30, 45, and 60 were used to estimate minutes per day. We modified the question order from the original version of the IPAQ and asked about daily walking before asking about other MPA. We modified the timing to ask about usual PA instead of PA in the past 7 days. Minutes per week in MPA were calculated as the sum of days per week multiplied by minutes per day in MPA and brisk walking. Minutes per week in VPA were calculated as the sum of days per week multiplied by minutes per day in VPA.

Participant characteristics and anthropometrics. At the baseline visit, we used a questionnaire to measure self-perceived general health and well-being and presence of chronic diseases. Using a digital scale, we weighed each participant twice and measured a third time if the two measures differed by more than 0.2 kg. Height was also measured twice to the nearest 0.5 cm using a height stadiometer and measured a third time if the two measures differed by more than 0.5 cm. The average of the two closest measures was used for height and weight. Body mass index (BMI) was calculated as weight (kg) divided by height (m²). Seated resting blood pressure was measured, in duplicate, using a digital Omron monitor after participants had been seated with legs uncrossed for at least 5 minutes. Blood pressure was measured a third time if the two measures differed by more than 4 mm Hg. The two closest measures were averaged and used for analyses.

Statistical analysis. Statistical analyses were performed using SAS version 8.2 (SAS Institute Inc, Cary, North Carolina) and SAS-callable SUDAAN software (RTI International, Research Triangle Park, North Carolina). We examined the magnitude of the intra-class correlation coefficient (ICC) among subjects from the same church, which was estimated to be 0.06. We used a SUDAAN modeling procedure with two levels of clustering (both church and individuals specified in the models) to account for the ICC among church members and temporal dependence in repeated observations obtained on the same individual. Working independence between participants from the same church was assumed, along with an exchangeable covariance structure for repeated measurements on the same individual. Least square means were obtained from the models along with standard errors, which were then converted into standard deviations for the adjusted mean changes.