The Japanese tradition of shinrin-yoku or “forest bathing" has inspired the modern concept of "forest therapy," or walking in the forest as a way to improve health and mood.
The recent study measured anxiety with the State–Trait Anxiety Inventory (STAI) and found that anxiety was significantly less for those that walked in the forest compared to those in the city. Furthermore, people who walked in the forest experienced significantly less negative feelings such as tension, anxiety, depression, anger, fatigue, and confusion.
Researchers examined heart rate, heart rate variability, and blood pressure and found that forest therapy activates the "relaxation response" branch of the nervous system, or parasympathetic nervous system.
Small studies have found that forest therapy can improve mood and reduce depressive symptoms, including a study in children. Forest walking can be especially useful since it combines mindfulness in nature with exercise: both of which are known to reduce depressive symptoms.
You do not have to walk for long periods in the forest order to reap the mental or physical benefits of forest therapy. Research has found that as little as 15 minutes of walking in the forest can make a big difference in putting your body and mind at ease.
Studies have found that walking in a forest could increase "natural killer" cell activity and boost immunity -- and these protective benefits can last over a month.
A small number of studies have measured antioxidant levels in the blood after forest bathing and found that helpful antioxidants increased significantly.