Dust off an old hobby.
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Whether it's blowtorch sculpting or shredding on a Tele, you once had a beloved hobby and you let it die. Pick it up again. Not only will you have fun, studies show that a challenging hobby reduces stress and lowers blood pressure. "People invested in positive experiences have greater longevity, living as much as nine years longer," says Harvard Medical School psychologist Carol Kauffman. "You have to do this. Fun is serious business."