Most adults with multiple sclerosis (MS) are physically inactive. One approach to address physical inactivity in this population has involved the provision of physical activity guidelines. Such physical activity guidelines are an important tool for exercise prescription, promotion, and monitoring, and recommend that people with MS "participate in at least 30 minutes of moderate intensity aerobic activity 2 times per week and strength training exercises for major muscle groups 2 times per week." The guidelines were developed from a systematic literature review and have yet to be tested for efficacy in improving fitness or other outcomes. This study will test that efficacy of aerobic and resistance training alone and in combination (based on the MS physical activity guidelines) for improving physical fitness and other outcomes (e.g., walking, thinking, MS symptoms) in persons with MS who have mild-to-moderate disability. Such an examination will be important to confirm the efficacy of the exercise prescription for people with MS and health-care providers. The investigators will further perform an exploratory analysis of blood biomarkers and eye imaging parameters to examine some of the mechanisms of exercise training effects in persons with MS.
