... it keeps him healthy, too. According to CNN, playing or listening to music opens up the blood vessels, allowing blood to course through more freely. It's an excellent de-stressor—a good thing since stress can tax both the heart and the immune system. (Dr. Mike Miller of the University of Maryland Medical Center in Baltimore says music "gives us an overall feeling of good, well-being -- a sense of euphoria in some cases.") The only caveat? You must actually like the music you listen to, since stress levels actually rise if you pick something you can't stand.