Shinrin-yoku was developed in the 1980s in Japan. Although people had been taking walks in the country’s forests for centuries, new studies showed that such activity could reduce blood pressure, lower cortisol levels and improve concentration and memory. A chemical released by trees and plants, called phytoncides, was found to boost the immune system. As more research highlighted the benefits of shinrin-yoku, the Japanese government incorporated it into the country’s health programme.
Read more here