Older adults benefit greatly from being physically active yet they are the least active generation. To appeal to older consumers, to reduce barriers older adults experience to becoming physically active and to increase the number of physically active older adults, the exercise market has been divided into mainstream fitness and age-segregated programming that specifically targets older adults. This research employed an institutional ethnography approach to understand better the social discourses and material practices that shape socially (in/ex)clusive physical cultures for older exercisers in both mainstream and older-adult group exercise classes. Textual analyses, interviews and field observations revealed that the material and discursive work practices intended to promote inclusivity in group exercise physical cultures actually engendered age-exclusive markets. Herein, we discuss how the guidelines and policies put forth by these certifying bodies, and the training curricula they publish, govern group exercise practices in a manner that tends to align with dominant ideological discourses conflating age and ability. We conclude by arguing that in order to create more inclusive physical cultures, mainstream fitness providers need to embrace options that appeal to potential group exercise consumers of all abilities, regardless of age.