This study evaluated the effect of distance on the likelihood of initiating and maintaining regular use of a fitness-program benefit in a population of managed Medicare seniors. We studied 8,162 participants and nonparticipants in a managed-care fitness-program benefit: a structured group exercise program or an unstructured health-club membership. Participants in both programs lived significantly closer to facilities than nonparticipants did (structured, p < .001; unstructured, p = .017). Participants living closer to unstructured-program sites attended more frequently than those farther away (p = .008). Distance was not correlated with frequency of use in the structured program (p = .49). Collectively, these analyses demonstrate that distance is related to uptake and, in some cases, continued use of a fitness-program benefit. Health systems providing fitness-program benefits as a way to increase physical activity levels of their plan members should consider location of program facilities in relation to members' home addresses to maximize use of the benefit.