Another reason to add more physical activity to a daily routine: Sedentary behavior has been found to increase depression and negatively affect mood and mental health in a recent study. The results, published in Mayo Clinic Proceedings, report a decline in mood and an increase in depression in participants who were asked to eliminate all exercise and minimize step counts to 5,000 or fewer for 1 week. Possible explanations for the results include both the psychological and the physiological. Mentally, exercise may translate to improved self-confidence in the ability to handle challenging events, and physically, endorphins and the transmission of serotonin and other chemicals in the brain improve with activity. After 1 week back to more active routines, the participants experienced improved moods and a drop in depression.