Embracing the natural world is deeply connected with well-being. Explore how the Japanese are healing stress by promoting this timeless behavior. Isn’t this better than taking medications or overeating? Feeling stressed out, go for a walk in the woods. It is probably wise to go with a friend or in a place not too isolated and enjoy yourself.
New York Times, July 6, 2010, page D5
The Claim: Exposure to Plants and Parks Can Boost Immunity
One study published in January included data on 280 healthy people in Japan, where visiting nature parks for therapeutic effect has become a popular practice called “Shinrin-yoku,” or “forest bathing.” On one day, some people were instructed to walk through a forest or wooded area for a few hours, while others walked through a city area. On the second day, they traded places. The scientists found that being among plants produced “lower concentrations of cortisol, lower pulse rate, and lower blood pressure,” among other things.

Trends in research related to “Shinrin-yoku” (taking in the forest atmosphere or forest bathing) in Japan.
Environ Health Prev Med. 2010 Jan;15(1):27-37.

Tsunetsugu Y, Park BJ, Miyazaki Y.

Forestry and Forest Products Research Institute, 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan, yukot@ffpri.affrc.go.jp.
Abstract

“Shinrin-yoku”, which can be defined as “taking in the forest atmosphere or forest bathing”, has been receiving increasing attention in Japan in recent years for its capacity to provide relaxation and reduce stress. Since 2004, the authors of this paper have been involved in an investigation designed to ascertain the physiological effects of “Shinrin-yoku” within the framework of the “Therapeutic Effects of Forests” project. We have conducted physiological experiments, both in actual forests and in the laboratory, to elucidate the physiological effects on individuals of exposure to the total environment of forests or to only certain elements of this environment, such as the odor of wood, the sound of running stream water, and the scenery of the forest. We have obtained physiological measurements of central nervous activity, autonomic nervous activity, and biomarkers reflecting stress response that can be applied in this line of approach. Using these measurements, we have summarized the separate elements of forests in terms of the five senses. We have also reviewed a selection of field studies and introduced a number of results from ongoing projects as well as those from early studies. Future perspectives are also discussed.

J Int Med Res. 2006 Mar-Apr;34(2):152-9.
The effects of exercise in forest and urban environments on sympathetic nervous activity of normal young adults.

Yamaguchi M, Deguchi M, Miyazaki Y.

Department of Material Systems Engineering and Life Science, Faculty of Engineering, University of Toyama, Toyama, Japan. yamag@eng.toyama-u.ac.jp
Abstract

In Japan, forest-air bathing and walking (shinrin-yoku) has been proposed as a health-facilitating activity in which people spend a short period of time in a forest environment. Initially, we examined the usefulness of salivary amylase activity as an indicator of an individual’s stress levels in a forest environment. The circadian rhythm of salivary amylase activity was measured in healthy young male subjects under stress-free conditions. The salivary amylase activity remained relatively constant throughout the day. Salivary amylase activity was then measured before and after walking in both urban and forest environments using a hand-held monitor. Our results indicated that (i) the circadian rhythm fluctuations in salivary amylase activity were much smaller than the stressor-induced variations; (ii) salivary amylase activity was an excellent indicator of the changes in sympathetic nervous activity; and (iii) the forest was a good environment in which people could experience much less environment-derived stress.