• Physical activity more effective against depression than anxiety
• Frequent exercise causes permanent reduction symptom severity
• Moderate to strenuous physical activity required, low-intensity barely helps

Adults with multiple sclerosis (MS), spinal cord injury, muscular dystrophy, or the post-polio syndrome can substantially reduce symptoms of anxiety and depression by frequently performing (moderate intensity) physical activity. Low-intensity physical activity seems insufficient to obtain significant improvements in psychological functioning. This can be concluded based on an American study in which researchers had 1,500 participants with a physical disability completing a variety of different questionnaires on baseline, at one year and at four years after baseline.