The present study was designed to examine the effects of long-term combined training on functioning in persons with MS in a randomized controlled trial. The secondary aim was, in a cross-sectional design, to explore the associations between exercise capacity, disability, and leisure-time physical activity (before the training intervention). The training intervention emphasized resistance exercises, but was complemented by endurance training. Subjects in the training group (n = 47) first attended supervised training for three weeks during an inpatient rehabilitation period, and thereafter continued training for 23 weeks at home. Subjects in the control group (n = 48) received no physical activity intervention. Assessments took place at baseline and at six months. The primary outcome was walking speed, measured by the timed 25-foot (7.62 m) Walk Test and 500-meter Walk Test. Secondary outcomes included measures of physical and mental functioning, disability, and health-related quality of life.