There are numerous physical, social and psychological benefits of exercise for persons with multiple sclerosis (MS), yet fewer than 20% of this population engage in sufficient amounts of exercise for health benefits. This low rate of exercise engagement may be associated with a lack of understanding regarding how persons with MS perceive exercise, and its meanings in the context of their lived experiences. This research explored how perceptions of exercise evolved over the course of living with MS. We conducted a structural narrative analysis on the testimonies of 50 individuals with MS, focusing on perceptions of exercise from pre-diagnosis through onset and diagnosis to future experiences with the illness. Two narratives were crafted reflecting the different evolutions of perceptions of exercise over time. The first, ‘the continuous exerciser’, reflected the experiences of individuals who continued exercise regardless of their MS diagnosis. The second, ‘the long-term non-exerciser’, reflected the experiences regarding individuals who were inactive over a prolonged period including before and after their diagnosis. The intersection of age, however, changed the meaning of exercise for older participants resulting in this behaviour becoming an important part of their lives. The crafting of these narratives sheds light on how and why perceptions of exercise may change over time, and provides a greater appreciation of the cultural, social and personal resources that shape perceptions of exercise. Future studies and interventions may be designed with a greater awareness of the meaning persons with MS ascribe to exercise over the span of living with MS.