Anxiety is a common, and often untreated, side effect of cancer. The stress of a cancer diagnosis, fear of the unknown, and uncertainty for the future are just a few things that can cause anxiety for patients and survivors, as well as for loved ones and caregivers. However, exercise can be a viable, non-pharmacological option to treat anxiety, says researchers of a review published this week in the Archives of Internal Medicine. Researchers reviewed 40 studies involving 2,914 sedentary patients with various chronic diseases, including cancer, and found that regular exercise decreased symptoms of anxiety by about 20 percent. Exercise sessions of 30 minutes were more effective than shorter periods. "The present analysis showed that exercise training reduces anxiety among patients with cancer. This observation differs from that of others who concluded that there was weak evidence for a consistent positive effect of increased physical activity on anxiety among cancer survivors. Our analysis differed in that in included both patients with cancer, who exercised during treatment, and survivors who exercised after treatment," concluded researchers.Other benefits of exercise are it can be relatively inexpensive, such as walking, and, in most cases, it doesn't interfere with treatment. This is all good news. However, if your anxiety becomes severe and exercise doesn't seem to help, please seek the advice of a health care provider.