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291
www.metla.fi/silvafennica · ISSN 0037-5330
The Finnish Society of Forest Science · The Finnish Forest Research Institute
SI LV A FE N N I C A
Silva Fennica 43(2) research articles
Physiological Effects of Forest Recreation
in a Young Conifer Forest in Hinokage
Town, Japan
Bum-Jin Park, Yuko Tsunetsugu, Tamami Kasetani, Takeshi Morikawa, Takahide Kagawa
and Yoshifumi Miyazaki
Park, B.J., Tsunetsugu, Y., Kasetani, T., Morikawa, T., Kagawa, T. & Miyazaki, Y. 2009. Physiological
effects of forest recreation in a young conifer forest in Hinokage Town, Japan. Silva Fennica
43(2): 291–301.
It is widely believed that coming into contact with forest environments is somehow beneficial
to human well-being and comfort. In Japan, “Shinrin-yoku” (taking in the atmosphere of a
forest) has been proposed to be a relaxation activity associated with forest recreation. The
purpose of this study was to examine the physiological effects of forest recreation on the
autonomic nervous activity. The subjects were twelve male university students (21.8 ± 0.8
years old). On the first day of the experiment, six subjects were sent to a forest area, and the
other six to a city area. On the second day, each subject was sent to the area he did not visit
on the first day as a cross check. The subjects walked (15 minutes) around their assigned
areas before noon, and sat on chairs viewing (15 minutes) the landscapes of their assigned
areas in the afternoon. Heart rate variability (HRV), blood pressure, and pulse rate were
measured as physiological indices. Measurements were taken at the place of accommodation
in the morning, before and after walking, and before and after viewing at their assigned field
areas. Pulse rate, diastolic blood pressure and LF/(LF+HF) (LF – low frequency, HF – high
frequency) components of HRV were significantly lower in the forest area than in the city
area. HF components of HRV tended to be higher in the forest than in the city. In conclusion,
the results of the physiological measurements show that forest recreation enabled effective
relaxation in people, both of the mind and body.
Keywords blood pressure, heart rate variability, pulse rate, relaxation, Shinrin-yoku, therapeutic
effects of forest, well-being
Addresses Chiba University, Center for Environment, Health and Field Sciences, Kashiwa-
no-ha 6-2-1, 277-0882 Kashiwa, Chiba, Japan
E-mail bjpark(at)faculty.chiba-u.jp
Received 26 June 2008 Revised 22 December 2008 Accepted 6 April 2009
Available at http://www.metla.fi/silvafennica/full/sf43/sf432291.pdf
292
Silva Fennica 43(2), 2009 research articles
1 Introduction
The growing interest in environmental stress has
been accompanied by a rapid accumulation of
evidence indicating that environmental stress (e.g.
crowding, community noise, air pollution) can
exert substantial stress on people living in urban
environments (Ulrich et al. 1991). Furthermore,
there is the broad perception that the natural
environment can enhance human health (Frumkin
2001). There have also been other studies show-
ing that contact with trees and plants in gardens
or urban parks makes people calmer and more
relaxed (Ulrich 1984, Ulrich et al. 1991, Honey-
man 1992, Kellert and Wilson 1993).
According to E.O Wilson’s hypothesis of
‘biophilia’ (1984), humans are innately attracted
to other living organisms. Furthermore, the
authors of ‘The Biophilia Hypothesis’ (1993)
have expanded this concept, suggesting that
humans have an innate bond with nature. This
implies that certain kinds of contact with the
natural world may benefit human health (Frumkin
2001). Physiological anthropology also suggests
that humans have lived in the natural environment
for most of the 5 million years of their existence.
Therefore, human physiological functions are
made for natural settings. This is the reason why
a natural environment enhances the relaxation of
human beings (Miyazaki et al. 2002).
“Shinrin-yoku” can be defined as making con-
tact with and taking in the atmosphere of the
forest. In Japan, forest bathing (“Shinrin-yoku”
in Japanese) is now receiving increased attention
for its effects of reducing stress and providing a
feeling of relaxation. “Shinrin-yoku” is a word
that was coined by the Forestry Agency of the
Japanese government when it brought out the
“Shinrin-yoku plan” in 1982. It is a compound
word made up of two independent words mean-
ing “forest” and “bathing.” Most likely, the word
“Shinrin-yoku” is intended to convey a concept
like sea bathing, of being in a forest environment
and taking in the atmosphere of the forest in
expectation of a potential curative or therapeutic
effect. Over the 25 years since then, interest
in stress control and relaxation has increased
in Japanese society. In addition to this, in the
fields of medicine and nursing, there has been a
trend towards evidence-based medicine or nurs-
ing, emphasizing scientific evidence in medical
practice. Against this social background, in 2004
the Forest Agency came out with the “Therapeutic
Effects of Forests plan.” This may be thought of as
an advanced version of the “Shinrin-yoku plan,”
the major difference being that it emphasizes
the importance of scientific investigation. The
aim of “Therapeutic Effects of Forests Plan” is
to collect data on the relaxation effects of forest
environments from the viewpoint of evidence
based medicine (EBM). We have collected data
to elucidate the effects of physiological relaxa-
tion provided by forests using 456 subjects and
38 forests studied over the period of 4 years. The
other aim of this plan is to authorize restorative
forest environments. One of the main criteria
of restorative forest is the physiological effects
attributable to the forest environments.
“Shinrin-yoku” is a process in which activi-
ties in forest environments are used to improve
the mental and physical health of people (Park
et al. 2007). Given this background, there have
also been other reports on “Shinrin-yoku”. We
have reported the physiological relaxation effects
of “Shinrin-yoku” from the perspective of the
autonomic nervous activity and stress hormones
(Park et al. 2007, Tsunetsugu et al. 2007, Park et
al. 2008). Further, studies have reported that the
mode of action of “Shinrin-yoku” can be recovery
of the immune system as determined from the
perspective of natural killer (NK) cells activity
(Li et al. 2007, Li et al. 2008a, Li et al. 2008b).
Furthermore, Ohtsuka et al. (1998) reported that
forest walking effectively decreases blood glu-
cose levels in diabetic patients. Therefore, the
study performed by Morita et al. (2006) demon-
strated the relaxation effects of “Shinrin-yoku”
by employing a questionnaire.
The physiological effects of the natural envi-
ronment have been studied indoors using natural
stimuli (visual, odoriferous, etc.) (Ulrich 1981,
Ulrich 1984, Miyazaki and Motohashi 1996). The
lack of field experiments in the 1980s and 1990s
was due to the limitations of physiological meas-
urements in field conditions. Field experiments
not only require the movement of the subjects
to be restricted to the experiment site, but also
require equipment that is difficult to transport and
power. However, in the mid-2000s, the physiolog-
293
Park, Tsunetsugu, Kasetani, Morikawa, Kagava & Miyazaki Physiological Effects of Forest Recreation in a Young Conifer Forest …
ical measurement technology available for field
experiments developed rapidly. Consequently,
several studies on the physiological effects of the
natural environment in field conditions have been
performed recently (Hartig et al. 2003, Park et al.
2007, Tsunetsugu et al. 2007, Park et al. 2008).
In the Europe, COST Action E39 (Forest and
Trees & Health and Human Well-being) per-
formed various studies on forest and human
health. With this background, studies on forests
and human health have been performed exten-
sively in Europe during the past few years (Kor-
pela et al. 2001, Hartig et al. 2003, Herzog et al.
2003, Laumann et al. 2003, Van den Berg et al.
2003, Hartig and Staats 2006).
The autonomic nervous system is a suitable
index for clarifying the physiological effects of
forest recreation. The autonomic nervous system
has been measured by using a variety of methods,
such as heart rate variability (HRV), pulse rate,
and blood pressure. It is a well-known fact that
autonomic nervous activity is a good indicator
of human body relaxation. Certain studies have
reported that increase in pulse rate and blood
pressure under the stress state was employed as
relaxation indicators in indoor and field experi-
ments (Ulrich 1981, Ulrich 1984, Miyazaki and
Motohashi 1996, Tsunetsugu et al. 2007, Park et
al. 2008). Furthermore, HRV can measure para-
sympathetic and sympathetic nervous activities,
which comprise the 2 branches of autonomic
nervous activity. Two major spectral components
of HRV were calculated, the low frequency (LF:
0.04–0.15Hz) component and the high frequency
(HF: 0.15–0.40 Hz) component (Task Force of the
European Society of Cardiology and the North
American Society of Pacing and Electrophysiol-
ogy 1996). HF power spectrum of HRV reflects
parasympathetic nervous activity (Cacioppo et
al. 1994), which increases under the relaxation
state, and LF/(LF+HF) of HRV reflects sympa-
thetic nervous activity (Weise and Heydenreich
1989), which increases under the stress state.
HRV was employed as a relaxation indicator in
field experiments (Tsunetsugu et al. 2007, Park
et al. 2008).
Tsunetsugu et al. (2007) reported that in forest
areas blood pressure and pulse rate were sig-
nificantly lower than in city areas. Moreover, the
power of HF components of HRV tended to be
higher and LF/(LF+HF) tended to be lower in
forests than in city settings. Park et al. (2007)
reported that cerebral activity in the prefrontal
area was significantly lower among the group
that stayed in the forest relative to the group that
stayed in the city area. Moreover, the concentra-
tion of salivary cortisol was significantly lower in
the forest than in the city area.
The purpose of this study is to examine the
physiological and therapeutic effects of forest rec-
reation by measuring autonomic nervous activity
and subjective feelings under field conditions.
2 Materials and Methods
2.1 Design of the Experiment
The study areas were located in Hinokage Town
and Hyuga City in Miyazaki Prefecture. Twelve
male university students (21.8 ± 0.8 years of
age) participated in the study as subjects. None
of the subjects reported a history of physical or
psychiatric disorders. The study was performed
under the regulations of the Institutional Ethical
Committee of the Forestry and Forest Products
Research Institute in Japan. On the day prior to
the experiments, subjects were fully informed
of the aims and procedures of the experiment
and their informed consent was obtained. After
being given an orientation to the experiment, the
subjects visited and previewed the experimental
sites in the forest and city areas. Next, practice
measurements of all of the physiological indices
and subjective feelings were conducted at the
place of accommodation. Identical single rooms
were prepared as lodgings for each subject and
identical meals and water were provided during
the experiments in order to control these back-
ground environmental conditions.
The subjects were randomly divided into two
groups. On the first day of the experiments, six
subjects were sent to a forest area, and the other
six subjects to a city area. On the second day of
the experiments, each subject went to the area he
had not visited on the first day in order to do a
cross check. The first measurement was taken in
the early morning at the place of accommodation
before breakfast (Morning; 06:15–07:15). Follow-
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Silva Fennica 43(2), 2009 research articles
ing the first measurement, subjects were sent to
either the forest or the city area using vehicles. It
took an hour to get to both the forest and city areas
from the place of accommodation. Upon arrival
in the given area, the subjects walked around the
given places for 15 minutes (Walking) before
noon. The subjects then sat on chairs and viewed
the landscapes for 15 minutes (Viewing) in the
afternoon (Fig. 1). The second and third measure-
ments were taken before ‘Walking’ (10:40–11:30)
and after ‘Walking’ (11:00–11:50). The fourth and
fifth measurements were taken before ‘Viewing’
(14:10–15:00) and after ‘Viewing’ (14:30–15:20).
These measurements were taken one person at a
time. In addition to these five measurements, the
R-R interval was measured continuously during
‘Walking’ and ‘Viewing’ at the given place. HRV
was calculated once per minute using the time
duration between two consecutive R waves (R-R
interval) data. The first 10 seconds of the first
minute were removed because of the noise gener-
ated when starting measurements.
2.2 Measurements
R-R interval of the electrocardiogram was
measured using a portable electrocardiograph
(Activtracer AC-301A, GMS, Japan). Three
disk electrodes were attached to the chest to
measure the R-R interval. The R-R interval data
were analyzed by the maximum entropy method
(Memcalc/win; GMS, Japan). It is considered
that HF power of HRV reflects parasympathetic
nervous activity (Cacioppo et al. 1994) and that
LF/(LF+HF) of HRV reflects sympathetic nervous
activity (Weise and Heydenreich 1989).
Pulse rate and blood pressure were measured
with a digital blood pressure monitor using the
oscillometric method (HEM-1000, OMRON,
Japan).
In order to compare exercise load during forest
and city walking, exercise load was estimated with
an activity monitor using 3-dimensional accelera-
tion sensors (Activtracer AC-301A; GMS, Japan).
There was no difference in exercise load between
Fig. 1. The scenery at the two experiment sites. Upper left: viewing the landscape in the forest area.
Upper right: walking in the forest area. Lower left: viewing the landscape in the city area. Lower
right: walking in the city area.
295
Park, Tsunetsugu, Kasetani, Morikawa, Kagava & Miyazaki Physiological Effects of Forest Recreation in a Young Conifer Forest …
forest-area walking and city-area walking.
Sensory evaluation was conducted after physi-
ological measurements at the place of accom-
modation in the ‘Morning’, and before ‘Walking’
and after ‘Walking’ at the given areas and before
‘Viewing’ and after ‘Viewing’ the landscape at the
given areas. The subjects were asked to evaluate
the given area and to graph it on two 13-point
scales along the following two dimensions: ‘feel-
ing of comfort’ and ‘feeling of calm.’ The sub-
jects were also asked to answer 30 questions to
ascertain the degree to which they felt refreshed
(Mackay et al. 1978). The questionnaire consists
of 30 items asking, for instance, if the respondent
feels sleepy or vigorous. The scale scores ranged
from 1 (to a great extent) to 4 (not at all).
A one-tailed t-test was used to compare the
physiological responses to the forest and city
areas. The Wilcoxon signed-rank test was used
to analyze the psychological effect. Statistical
analysis of physiological data was processed with
EXCEL 2003 (Microsoft Inc.) and subjective data
was processed with StatView version 5.5 (SAS
Institute Inc.). Moreover, p < 0.05 was considered
to be signifi cant.
3 Results
Figs. 2, 3, and 4 show the results of the psycho-
logical assessment to ascertain the effects of forest
recreation. Fig. 2 shows the scores for ‘feeling
of comfort’ recorded in the forest and city areas.
The score for ‘feeling of comfort’ in the forest
area (Moderately comfortable) was signifi cantly
higher (p < 0.01) than in the city area (Moderately
uncomfortable) at the stage after ‘Walking.’ At
the stage after ‘Viewing,’ the score for ‘feeling of
comfort’ in the forest setting (Moderately com-
fortable) was also signifi cantly higher (p < 0.01)
than in the city setting (Moderately uncomfort-
able).
Fig. 3 shows the scores for ‘feeling of calm’
recorded in the forest and city areas. At the stage
after ‘Walking,’ the score for ‘feeling of calm’
Fig. 2. Change in subjective feelings of comfort in forest
and city areas. N = 11–12, Mean ± SD, **: p < 0.01,
by Wilcoxon signed-rank test.
Fig. 3. Change in subjective feelings of calm in forest
and city areas. N = 11–12, Mean ± SD, **: p < 0.01
by Wilcoxon signed-rank test.
Fig. 4. Change in subjective feelings of refreshment
in forest and city areas. N = 12, Mean ± SD,
**: p < 0.01 by Wilcoxon signed-rank test.
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Silva Fennica 43(2), 2009 research articles
in the forest area (Moderately soothing) was
significantly higher (p < 0.01) than for the city
area (Slightly awakening). Likewise, the score
for ‘feeling of calm’ in the forest area (Moder-
ately soothing) at the stage after ‘Viewing’ was
significantly higher (p < 0.01) than in the city area
(Slightly awakening).
Fig. 4 shows the scores for ‘feeling of refresh-
ment’ recorded in the forest and city areas. The
score for ‘feeling of refreshment’ in the forest area
after ‘Walking’ was significantly higher (p < 0.01)
than the score in the city area. At the stage after
‘Viewing,’ the score for ‘feeling of refreshment’
was also significantly higher (p < 0.01) in the
forest than in the city area.
Figs. 5, 6, and 7 show the results of physiologi-
cal assessments to ascertain the effects of forest
recreation. Fig. 5 shows the average diastolic
blood pressure in both forest and city settings.
Diastolic blood pressure was significantly lower
in the forest area before ‘Walking’ (p < 0.05),
after ‘Walking’ (p < 0.05) and after ‘Viewing’
(p < 0.01) than in the city area. At the stage before
‘Viewing,’ diastolic blood pressure in the forest
area tended to be lower (p < 0.07) than in the city
area.
Fig. 6 shows the average pulse rate in the forest
and city areas. Pulse rate was significantly lower
(p < 0.01) in the forest area after ‘Walking,’ before
‘Viewing’ and after ‘Viewing.’ At the stage before
‘Walking,’ pulse rate in the forest area tended to
be lower (p < 0.07) than in the city area.
Fig. 7 shows the average HF component of
HRV every minute. During ‘Walking’ around
the assigned places, the HF component in forest
areas tended to be higher than in city areas.
Moreover, a significant difference was obtained
at 4 minutes and 5 minutes (p < 0.05) after the
starting point. The HF component tended to be
higher than in city areas during ‘Viewing’ of the
landscape, and a significant difference in the HF
component between the two areas was obtained
Fig. 5. Change in average diastolic blood pressure
in forest and city areas. N = 12, Mean ± SD,
**: p < 0.01, *: p < 0.05, p-value by paired t-test.
Fig. 6. Change in average pulse rate in forest and city
areas. N = 12, Mean ± SD, **: p < 0.01, p-value by
paired t-test.
Fig. 7. Change in average HF power of HRV per minute
in forest and city areas. N = 10–12, Mean ± SE,
*: p < 0.05, p-value by paired t-test.
297
Park, Tsunetsugu, Kasetani, Morikawa, Kagava & Miyazaki Physiological Effects of Forest Recreation in a Young Conifer Forest …
at 1 minute and 10 minutes (p < 0.05) after the
starting point.
Fig. 8 shows the average LF/(LF+HF) compo-
nent of HRV every minute. For ‘Walking’ around
the assigned places, the LF/(LF+HF) component
in forest areas tended to be lower than in city areas.
Moreover, a significant difference was obtained
at 14 minutes (p < 0.05) after the starting point.
The LF/(LF+HF) component was significantly
lower in the forest area during ‘Viewing’ of the
landscape, and a significant difference in the LF/
(LF+HF) component between the two areas was
obtained at 5 minutes, 8 minutes and 13 minutes
(p < 0.05) after the starting point.
4 Discussion
The results of psychological measurements after
‘Walking’ and after ‘Viewing’ show that forest
settings produced significantly more comfort-
able, calmer and more refreshed feelings in the
subjects than the city setting. On the day prior
to the experiments, subjects were fully informed
about the aims and procedures of the experi-
ment. If the subject participated without proper
information on the aims of the study, especially
when he is participating in the measurement for
the first time, they could experience nervousness.
This is why we informed the subjects about the
aim of study prior to the start of the experiments.
However, it can affect the results of the self-
evaluation report.
The studies of Park et al. (2007), Tsunetsugu et
al. (2007) and Park et al. (2008)’s field test have
reached the same conclusion. Based on these
studies, walking in a forest setting and viewing
forest landscapes can be considered to be effec-
tive in providing relaxation to people as compared
to a city setting. This result strongly supports
the results of research about positive emotions
among subjects who were shown pictures of natu-
ral environments (Blood et al. 1999, Buchanan
et al. 2000, Goel and Dolan 2000, Iidaka et al.
2001). This result also supports the finding that
forest environments improved the psychological
wellness of people (Herzog et al. 1997, Kaplan
1984, 2001, Kaplan and Talbot 1983, Talbot and
Kaplan 1986).
Pulse rate and diastolic blood pressure in the
forest area were significantly lower than in the
city area after ‘Walking’ and after ‘Viewing.’
This shows that the forest setting had a significant
relaxing effect on the human body compared to
city settings. At the stages before ‘Walking’ and
before ‘Viewing,’ pulse rate and diastolic blood
pressure in the forest area were significantly lower
or tended to be lower than in the city area. This
result suggests that forest settings and city settings
already had different impacts on physiological
conditions before the activities commenced (Park
et al. 2007, Tsunetsugu et al. 2007). The subjects
were exposed to given places before walking and
viewing; therefore, this kind of exposure affects
the difference in blood pressure and pulse rate
in subjects before ‘Walking,’ and before ‘View-
ing.’
The LF/(LF+HF) component of HRV meas-
urements was significantly lower in the forest
area than in the city area when ‘Viewing’ the
landscape. The sympathetic nervous system pre-
dominates when a person is stressful. The value of
the LF/(LF+HF) component increases when the
sympathetic nervous system is activated. We did
not know the reason why there is the difference
between 1 and 10 minutes in HF and 5, 8 and 13
minutes in LF/(LF+HF). However, we were to
show that there was the point showing significant
difference and that there was tendency of differ-
ence during 15 minutes of walking and watch-
ing. In this field test, the result of LF/(LF+HF)
components showed that it is easy to ease the
human body in the forest setting in comparison
Fig. 8. Change in average LF/(LF+HF) of HRV per
minute in forest and city areas. N = 10–12, Mean
± SE, *: p < 0.05, p-value by paired t-test.
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Silva Fennica 43(2), 2009 research articles
to the city setting.
The relationship between respiration and heart
rate variability (HRV) has been well-established.
Researchers have been advocating the necessity
for controlled breathing to avoid respiratory
interference with HRV components (Brown et
al. 1993, Kobayashi et al. 1999, Camman and
Michel 2002). However, it is difficult to apply the
technique of controlled breathing in field studies;
in this case, HRV is frequently measured under
spontaneous breathing conditions. Studies have
been conducted on quantitative examinations of
the effect of controlled breathing on reliability of
HRV measurements. There have also been other
studies that reported significant improvements in
the reliability of the measurements by controlled
breathing (e.g., Carrasco et al. 2003, Pinna et al.
2007); however, others have demonstrated that
controlled breathing was not sufficiently effec-
tive. Further, in certain cases, controlled breathing
decreased the reliability of the measurement (e.g.,
Reland et al. 2005, Tarkiainen et al. 2005). From
the above findings, the necessity for controlled
breathing appears to be inconclusive.
To minimize the exclusive effects of walking,
we controlled the walking conditions. At first, we
set up experimental roads that had no slope. Sec-
ondly, prior to the day of the first experiment day,
the subjects walked on the forest and city experi-
mental roads. Further, they were asked to main-
tain the same pace when they walked on forest
and city experimental roads. Finally, we checked
exercise loads in order to compare the exercise
loads during forest and city walking. Exercise
load was estimated with an activity monitor using
3-dimensional acceleration sensors (Activtracer
AC-301A; GMS, Japan). There was no difference
in exercise load between forest-area walking and
city-area walking.
The results of physiological measurements
strongly supports the result of the indoor research
using heart rate and blood pressure on the effect
of viewing a forest scene on recovery from stress
(Ulrich 1981, Ulrich et al. 1991). The results
were also consistent with the finding of Park et
al. (2008), which reported physiological effects
from “Shinrin-yoku” using salivary cortisol, pulse
rate and HRV as indicators, Park et al. (2007),
which reported physiological effects from forest
settings using salivary cortisol and cerebral activ-
ity as indicators, and Tsunetsugu et al. (2007),
which reported physiological effects from forest
environments using salivary cortisol, pulse rate,
blood pressure and HRV. Moreover, Yamaguchi et
al. (2006), reported exercise effects from forestry
using salivary amylase activity.
With respect to the visiting span, there have also
been other reports on the relationship between
length of visit and recovery of immune function
(Li et al. 2007, Li et al. 2008a, Li et al. 2008b).
The results of these papers showed that 3-day/2-
night stay in the forest setting can aid the recov-
ery of immune function. Furthermore, recovered
immune function lasted for more than 7days fol-
lowing a 3-day/2-night stay in the forest.
In addition, the results of physiological meas-
urements showed that the physiological responses
of the autonomic nervous system (pulse rate,
diastolic blood pressure and HRV) reflected the
relaxing effects of forest environments.
During this study, effects from other factors
were minimized to clarify the differences in
the effect on physiological and psychological
relaxation of humans from forestry and urban
surroundings. Other surrounding factors such as
accommodation, food, water intake or quantity
of exercise etc. were controlled so as to be the
same and thus to minimize their influence. The
subject group was limited to 12 persons so that
conditions could be controlled in detail during the
study. Subjects were also narrowed down to male
students in their early twenties, as the number of
subjects was limited. Also, the forests used for
field studies were limited to young conifer forests.
To remove this limitation, we have conducted
experiments of the same design in 38 different
types of forest. We also have plans to collect
data from 100 more fields with 1200 subjects in
Japan. We expect to be able to clarify the differ-
ences between the relaxing effects of different
forest types when we have finished collecting
this data.
In summary, in the forest area, 1) pulse rates
were significantly lower; 2) diastolic blood pres-
sure was significantly lower; 3) the HF component
tended to be higher; 4) the LF/(LF+HF) compo-
nent was significantly lower; 5) the subjective
‘feeling of comfort,’ ‘feeling of calm’ and ‘feeling
of refreshment’ were significantly higher than in
the city area. Furthermore, the autonomic nervous
299
Park, Tsunetsugu, Kasetani, Morikawa, Kagava & Miyazaki Physiological Effects of Forest Recreation in a Young Conifer Forest …
activity measurements proved that the subjects
felt more relaxed when viewing or walking in
the forest setting than when viewing or walking
in the city setting. Further, these values showed
that forest recreation had a significant relaxing
effect on the human body and mind.
Acknowledgments
The authors wish to thank Dr. Eeva Karjalainen
for her special advice. This study was partly sup-
ported by a Grant-in-Aid for Scientific Research
(S: 16107007) from The Ministry of Education,
Culture, Sports, Science and Technology (MEXT)
– Japan.
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