Effects of "shinrin-yoku (forest-air bathing and walking)" on psychological, physiological, and immunological aspects were examined. Twenty (10 male and 10female) undergraduates stayed in a forest environment and in a non forest environment for about 8 hours and they performed two types of acute stress tasks (Stroop task as a mental stressor and cold pressor as a physical stressor) in each environment. The subjects rated their affective states and their blood and urine were drown at the beginning and at the end of each experimental session. Immunological indexes (NK cell activity, immunoglobulin M, G, and A) and endocrine indexes (cortisol, cathecolamines) were assessed from their blood and urine samples. Subjects\u27 humoral immune levels (salivary immunoglobulin A), an endocrine measure (salivary cortisol), and psychological states (state anxiety and subjective stress) were evaluated before and after exposure to the stress tasks. Also, EEG, BOG, and ECG were measured during the Stroop task. The results of immunological indexes demonstrated that exposure to the forest environment effectively increased cellular and humoral immune activity. This finding implicated that shinrin-yoku has some positive effects for health promotion
