Background: Exercise is Medicine is a global health initiative launched by the American College of Sports Medicine and the American Medical Association that aims to make physical activity assessment and promotion a standard part of clinical care for people of all abilities. Utilizing a standardized physical activity vital sign at every office visit may serve as a basis for further counseling and medical care. To our knowledge our study is the first time the physical activity vital sign has been widely utilized in an academic multiple sclerosis center. Objectives: This study evaluated self-reported exercise participation in a sample of patients from an academic multiple sclerosis center using a standardized physical activity vital sign, and assessed its association with demographic characteristics and functional measures. Methods: As part of the routine rooming process for in-person and telemedicine visits, patients presenting to a university multiple sclerosis center were asked how many days per week they performed moderate-to-vigorous intensity exercise and, on those days, on average how many minutes they exercised at that level. Data obtained from the electronic health record included total weekly exercise (in minutes), age, gender, race, ethnicity, type of visit, BMI, 25-foot walk time, use of mobility aid, PHQ-2 score, and degree of self-reported problems with fatigue, pain, heat sensitivity, weakness, falling, and depression (not at all, a little bit, quite a bit, or very much). Results: Data were analyzed for 1,142 unique patients at the multiple sclerosis center. Overall, patients reported a median exercise time of 80 minutes per week and a mean exercise time of 120 minutes per week. 30.2% reported exercising at or above 150 minutes per week, and 25.2% reported no moderate-to-vigorous exercise. BMI was negatively associated with levels of activity (Spearman correlation: -0.19, p<0.001). Longer time to complete 25-foot walk test was negatively associated with total exercise time (Spearman correlation: -0.23, p<0.001). No association was found with age or gender. Median total minutes of exercise decreased with increasing report of problems with fatigue, pain, heat sensitivity, weakness, falling, and depression. Conclusions: Only 30.2% of patients seen at this university multiple sclerosis center met the recommended weekly exercise amount based on the U.S. national physical activity guidelines. Shorter exercise times were associated with higher BMIs and slower walk speeds. Causal effects cannot be inferred from this study, but future studies might incorporate interventions to improve MS-related symptoms and lower BMI to facilitate better exercise participation in this population.