Project Summary/Abstract African American (AA) women experience disproportionately higher rates of chronic diseases compared to White women, including being twice as likely to die from cardiovascular disease. Physical activity (PA) is a key protective factor for reducing risk for chronic diseases, yet only 35% of AA women meet national PA guidelines. Persistent disparities in chronic disease and pre-mature death among African American women across the adult lifespan highlight the need for developing effective interventions for increasing PA among AA women. We propose that community settings hold tremendous promise as an important context for reaching AA women, but the role of social affiliation has been understudied in past community-based interventions as a key mechanism for engaging AA women in long-term PA. A variety of theories have highlighted the importance of social affiliation for health promotion and have defined social affiliation through several distinct but related constructs. Social Cognitive Theory (SCT) proposes that the group context promotes social learning and collective efficacy, while Self-Determination Theory (SDT) and Group Dynamics Theory (GDT) have emphasized the importance of positive interactions between group members in order to promote relatedness, reciprocal support, and group cohesion. Social affiliation within group-based programs may be especially important to AA women, given that collectivism (belief in the importance of advancing the group over the individual) is a prominent cultural value for many AAs. Despite converging evidence highlighting the importance of social affiliation from a motivational and cultural perspective, this factor has been minimally integrated within intervention designs and rarely targeted as a central mechanism for increasing PA. Our investigative team provides strong preliminary data for expanding on previous community-based PA interventions for inactive AA women by targeting social affiliation through a combination of collaborative and competitive strategies. Drawing from SDT, SCT, GDT, and a cultural values framework, The Together Everyone Achieve More Physical Activity (TEAM-PA) trial evaluates the efficacy of a group-based social affiliation intervention (vs. a standard group-delivered PA comparison program) for increasing PA among inactive AA women. Using a group cohort randomized design implemented at community centers across five years, the primary aim of this study is to evaluate the efficacy of the 10-week TEAM-PA group-based intervention (vs. comparison program) on increasing accelerometry-assessed minutes per day of total PA (light to vigorous activities) from baseline to post-intervention and maintenance at a 6-month follow-up [Primary Aim 1]. Additionally, we will evaluate the impact of the TEAM-PA intervention on secondary outcomes (percentage meeting national recommendations for PA, light PA, sedentary behavior, body mass index, blood pressure) [Secondary Aims 1-2] and pot...