This study was one of three modules in a larger study designed to define, identify, and disseminate information about best practice physical activity programming in community-based organizations. The National Council on the Aging (NCOA), together with the Robert Wood Johnson Foundation (RWJF), conducted Module 1, a national competition for NCOA Awards for Excellence in Physical Activity Programming. The purpose of the competition was to bring national attention to best practice in physical activity programming operated by local public or non-profit organizations that serve older adults. NCOA was assisted in this endeavor by the University of Illinois at Chicago (UIC), the Healthy Aging Research Network of the Centers for Disease Control and Prevention's Prevention Research Centers, and a variety of nationally known physical activity experts. Module 2 was a census of physical activity programs for older adults that was conducted in seven locations by Healthy Aging Research Network. Module 3 was this National Impact Study, a study of best practice programming at three community-based organizations serving older adults. It was designed to answer the research question, "Do best practice physical activity programs provided by community-based organizations have a measurable impact on the health and well being of participants?" The three studied organizations were among the ten winners of the best practice competition.

Data were collected from previously sedentary, volunteer participants from each of the three organizations. The goal was to enroll 250 older adults at each site for a total of 750 subjects across the three programs. At each site, one half of all subjects (n = 125) were to be assigned to the treatment group and the other half to a control group. Subjects in the treatment group participated in the best practice program classes while the control group could enroll in other exercise classes but not the best practice program classes. The subjects were to be interviewed three times: baseline, three months, and nine months. Each interview contained two parts: (1) the administration of health and exercise related questions and (2) the administration of four physical fitness tests that assessed the respondent's strength, flexibility and aerobic endurance. Background information collected by the survey includes age, education, employment status, marital status, income, race, and Hispanic origin.