Physical activity and its measurement and determinants in multiple sclerosis.

This literature review provides a description of research on physical activity behavior and its measurement and determinants in persons affected by multiple sclerosis (MS). Overall, there is fairly strong and consistent evidence that individuals with MS are largely inactive compared with non-diseased populations, and this rate of inactivity is alarming given the prevalence of inactivity among the general population. Importantly, there has been some concern with the measurement of physical activity in persons with MS, but this concern recently has been allayed by the systematic provision of evidence supporting the validity of both objective and self-report instruments in individuals with MS. Such evidence has enhanced the capacity of researchers for examining determinants of physical activity in persons with MS, and the emerging research has highlighted the role of symptoms in explaining inactivity in this population. As this body of research expands further, there will be a better basis for conducting targeted and well-designed interventions for promoting physical activity among those with MS. Efforts toward increasing physical activity in those with MS will go along way in promoting the many physiological and psychological consequences of an active lifestyle.