Physical Activity and Its Correlates in Youth with Multiple Sclerosis.

OBJECTIVES: To investigate physical activity levels in youth with multiple sclerosis and monophasic acquired demyelinating syndromes ([mono-ADS], ie, children without relapsing disease) compared with healthy controls and to determine factors that contribute to engagement in physical activity. We hypothesized that greater physical activity goal setting and physical activity self-efficacy would be associated with greater levels of vigorous physical activity in youth with multiple sclerosis. STUDY DESIGN: A total of 68 consecutive patients (27 multiple sclerosis, 41 mono-ADS) and 37 healthy controls completed fatigue, depression, Physical Activity Self-Efficacy Scale, perceived disability, Exercise Goal-Setting scale, and physical activity questionnaires, and wore an accelerometer for 7 days. All patients had no ambulatory limitations (Expanded Disability Status Scale, scores all <4). RESULTS: Youth with multiple sclerosis engaged in fewer minutes per day of vigorous (P = .009) and moderate and vigorous physical activity (P = .048) than did patients with mono-ADS and healthy controls. A lower proportion of the group with multiple sclerosis (63%) reported participating in any strenuous physical activity than the mono-ADS (85%) and healthy control (89%) groups (P = .020). When we adjusted for age and sex, the Physical Activity Self-Efficacy Scale and Exercise Goal-Setting scale were associated positively with vigorous physical activity in the group with multiple sclerosis. Fatigue and depression did not predict physical activity or accelerometry metrics. CONCLUSIONS: Youth with multiple sclerosis participate in less physical activity than their counterparts with mono-ADS and healthy controls. Physical activity self-efficacy and exercise goal setting serve as potentially modifiable correlates of physical activity, and are measures suited to future interventions aimed to increase physical activity in youth with multiple sclerosis.