Even a single dance session can have a significant impact: in a German study from 2007, psychologists invited a group of patients who had been hospitalized for depression to dance to the Jewish folk song Hava Nagila for half an hour. After just thirty minutes, they scored higher on measures of vitality and lower on symptoms of depression. (This effect can’t be attributed to the joyful music alone: patients who spent the same half-hour period listening to the song without dancing actually wound up feeling more depressed.)
