Time among trees is associated with lower cortisol. Field studies in Japan found lower stress markers after forest walks compared with city walks. Samples were small.
The physiological effects of Shinrin-yoku: evidence from field experiments in 24 forests across Japan
What they found
After walking in and viewing forests, participants had lower salivary cortisol, pulse rate and blood pressure than after the same activity in city settings.
Limits to keep in mind
Only young Japanese men, measured over a day or two. We don’t know how long the effect lasts or how well it applies to everyone.
How we use it
Forest sits and slow walks on immersion days.