On weekends, overstimulated Tokyo-ites head to the sylvan hills outside the capital for the Japanese pastime of Shinrin-yoku, or "forest-bathing." Recent research shows that they're on to something: Scientists from Chiba University have found that compared with city strolls, leisurely walks in nature result in a 12.4 percent decrease in the stress hormone cortisol, a 7 percent decrease in sympathetic nerve activity, a 1.4 percent decrease in blood pressure and a 5.8 percent decrease in heart rate. Those studies have also shown that spending time outside can increase parasympathetic nerve activity by 55 percent , which, the researchers said, is associated with a relaxed state.
Recommended dosage: You'll boost your mind in as little as 5 minutes spent outdoors,according to research by Jules Pretty, a professor of environment and society at the University of Essex. However, an entire day outdoors can bring even greater benefits.