A study by King’s College London last year found that being among trees and hearing birdsong improved mental well-being, and the effect lasted for hours. Other studies suggest that a forest environment can lower blood pressure and the stress hormone cortisol. Forty years ago the Japanese government initiated Shinrin-yoku, a 'woodland bathing' activity to help business people to de-stress.
So, for a rapid and effective de-stressor, leave the phone behind (or in your pocket) and take a walk through the park, woods or other outdoor space and see how it benefits you... Let us know how you get on.