Growing research suggests regular physical activity as a strategy for reducing risk of Alzheimer's disease (AD); however, there is little research available regarding public messages about the connection between physical activity and brain health. This study aimed to (a) examine the volume and content of regular physical activity and brain health messages being distributed by national organizations, and (b) explore how informal caregivers perceive and comprehend brain health messages. Methods included (a) a content analysis of 155 online documents related to physical activity and aging that were located on national physical activity organizations' websites, and (b) a thematic analysis of transcripts and observer notes from two focus groups with 10 informal caregivers recruited at a support organization for AD caregivers in the southeastern United States. Content analysis results revealed limited information about the physical activity and brain health connection. Focus group results revealed that caregivers had limited exposure to information about the physical activity and brain health connection and were concerned about the credibility of this information. Further research is needed regarding brain health and physical activity messages and the potential benefits of collaboration among physical activity organizations, researchers, and health care professionals in delivering consistent and credible messages to the public.