The promotion of physical activity for people with multiple sclerosis (MS) would benefit from information about the common types of physical activity self-selected by this population. This study examined the most frequent types of physical activity self-reported by a large sample of people with MS. The data were collected as part of the baseline assessment of a longitudinal investigation of physical activity in relapsing-remitting MS (RRMS). The participants (N = 272) were sent a battery of questionnaires through the US Postal Service that included the Modifiable Activity Questionnaire for assessing types of physical activity performed during the previous year. Walking was ranked number 1 for both the first and second most common types of physical activity self-selected by people with MS, and it was ranked number 4 as the third most common type of self-selected physical activity. Collectively, 79% of the sample reported walking as a frequent form of self-selected physical activity in the previous year. Other notable types of physical activities self-selected by people with MS were gardening (44%), weight training (34%), bicycling (30%), and calisthenics (20%). This information may assist clinicians and practitioners in the development of physical activity programs and recommendations for people with MS. Int J MS Care. 2011;13:16-20.T he study of physical activity behavior and its consequences among people with multiple sclerosis (MS) is of increasing interest. Existing research has indicated that individuals with MS are generally physically inactive and sedentary, 1 but that physical activity is associated with many desirable outcomes in this population, including improvements in symptoms, function, disability, and quality of life.2,3 This paradox may be related to the recommendation by clinicians of a sedentary lifestyle among people with MS as a means of avoiding fatigue. This belief has been refuted by more recent evidence-based research, and there is emerging interest among clinicians and practitioners in the promotion of physical activity as an integral part of treatment and health maintenance in those with MS.In order to promote physical activity in this population, a comprehensive understanding of the actual types of physical activity self-selected by people with MS would be beneficial. To date, limited information is available on the different modes of physical activity performed by individuals with MS, 1 but such information is important for four primary reasons. First, clinicians and practitioners who recommend physical activity to their patients with MS would benefit from knowing the most frequent types of physical activity self-selected in this population. Second, such information would set the research agenda for evaluating the consequences of the most frequent types of physical activity self-selected in people with MS. Third, this information would better inform the development and validation of outcome measures for quantifying frequent types of physical activity in people with MS. Finally, such in...