Does a walk outside really clear your head?
· Source: Bratman, Hamilton, Hahn, Daily & Gross, PNAS, 2015
When a thought keeps looping, people tell you to go for a walk. In 2015, a team in California tested whether it matters where you walk. Healthy city dwellers each walked alone for ninety minutes. Half went through grassland with oak trees, the others along a busy road. Both routes were the same length, about five kilometres. After the green walk, people reported a bit less brooding, and a brain area linked to it was less active. After the road walk, neither changed. It was a small study, and a small change. But the place seemed to matter. So next time a worry won't let go, find somewhere green, and notice what catches your eye. Back home, say the thought once.