International Journal of
Environmental Research
and Public Health
Article
Assessing the Impact of a Shinrin-Yoku (Forest Bathing)
Intervention on Physician/Healthcare Professional Burnout:
A Randomized, Controlled Trial
John Kavanaugh 1,*, Mark E. Hardison 2, Heidi Honegger Rogers 3, Crystal White 2 and Jessica Gross 4
1 Department of Psychiatry and Behavioral Sciences, University of New Mexico Hospital,
University of New Mexico School of Medicine, Albuquerque, NM 87106, USA
2 Occupational Therapy Graduate Program, University of New Mexico, Albuquerque, NM 87131, USA
3 College of Nursing, University of New Mexico College of Nursing, Albuquerque, NM 87131, USA
4 Clinical and Translational Science Center, University of New Mexico Health Science Center,
Albuquerque, NM 87131, USA
* Correspondence: jpkavanaugh@salud.unm.edu
Citation: Kavanaugh, J.; Hardison,
M.E.; Rogers, H.H.; White, C.; Gross,
J. Assessing the Impact of a
Shinrin-Yoku (Forest Bathing)
Intervention on Physician/Healthcare
Professional Burnout: A Randomized,
Controlled Trial. Int. J. Environ. Res.
Public Health 2022, 19, 14505. https://
doi.org/10.3390/ijerph192114505
Academic Editors: Amber L.
Vermeesch, Andrew Lafrenz
and Chloé Littzen
Received: 20 September 2022
Accepted: 1 November 2022
Published: 4 November 2022
Publisher’s Note: MDPI stays neutral
with regard to jurisdictional claims in
published maps and institutional affil-
iations.
Abstract: Professional healthcare worker burnout is a crisis in the United States healthcare system.
This crisis can be viewed at any level, from the national to local communities, but ultimately, must be
understood at the level of the individual who is caring for patients. Thus, interventions to reduce
burnout symptoms must prioritize the mental health of these individuals by alleviating some of the
symptoms of depression, grief, and anxiety that accompany burnout. The practice of Shinrin-Yoku
(Forest Bathing) is a specific evidence-based practice which research has shown can improve an
individual’s mental health and, when performed in a group, can support a sense of social connection.
We investigated the impact of a three-hour, guided Shinrin-Yoku (Forest Bathing) nature-based
intervention on burnout symptoms among physicians and other healthcare workers by using a
randomized, controlled trial. The Oldenburg Burnout Inventory (OLBI) and Mini-Z assessments were
used to collect baseline burnout scores and participants were randomized into the intervention group,
which completed the assessment again after the Shinrin-Yoku walk, or into a control group, which
completed the assessments again after a day off from any clinical duties. A total of 34 participants
were enrolled in the intervention group and a total of 22 participants were enrolled in the control
group. Ultimately, no statistically significant differences were detected between the pre-test and
post-test scores for the intervention group or between the post-test scores of the intervention group
compared to the control group. However, the subjective responses collected from participants after
participating in the Shinrin-Yoku walk overwhelmingly reported decreased feelings of stress and
increased mental wellbeing. This raises important questions about the difference between symptoms
of burnout and other aspects of mental health, as well as the limitations of a one-time nature-based
intervention on levels of chronic burnout symptoms. Thus, further research on the effects of engaging
healthcare providers in an ongoing practice of Shinrin-Yoku is warranted.
Keywords: forest bathing; Shinrin-Yoku; forest therapy; professional burnout; healthcare providers
Copyright: © 2022 by the authors.
Licensee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and
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Attribution (CC BY) license (https://
creativecommons.org/licenses/by/
4.0/).
1. Introduction
Shinrin-Yoku (forest bathing) is the practice of “visiting a forest or engaging in various
therapeutic activities in a forest environment to improve one’s health and wellbeing” [1].
More specifically, it is an intentional practice in which the practitioner immerses themselves
in nature while mindfully giving attention to the sensory information they receive from
that natural environment. Forest Bathing as a term was coined by the Japanese government
in 1982, and since this time, researchers around the world have been assessing the impact
of Forest Bathing on a wide variety of physiological and psychological variables. These in-
clude potential benefits for immune system function (increase in natural killer cells/cancer
Int. J. Environ. Res. Public Health 2022, 19, 14505. https://doi.org/10.3390/ijerph192114505
https://www.mdpi.com/journal/ijerph
Int. J. Environ. Res. Public Health 2022, 19, 14505
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prevention), the cardiovascular system (hypertension/coronary artery disease), the respira-
tory system (allergies and respiratory disease), depression and anxiety (mood disorders
and stress), mental relaxation (attention deficit/hyperactivity disorder) and human feelings
of “awe” (increase in gratitude and selflessness) [2]. In a study conducted in Japan in
2019 to evaluate the effects of Forest Bathing on working age adults with high stress and
depressive tendencies, a two-hour Forest Bathing activity was shown to decrease blood
pressure and alleviate negative psychological parameters, especially in participants with
depressive tendencies [3]. Some benefits from a single Forest Bathing experience, such as
the improved functioning of natural killer (NK) cells, have been found to persist for up to
30 days [4]. Based on the demonstrated health benefits of Forest Bathing, researchers have
stated the need for further research in the “areas of healthcare professional stress reduction
and life balance” [2].
Professional burnout is of increasing concern within the healthcare system, both in
terms of the mental health of the providers as well as the impact it has on the quality and
safety of patient care. Burnout is an unfortunately prevalent syndrome among physicians
and other healthcare workers and the symptoms can consist of emotional exhaustion,
depersonalization, and feelings of low personal accomplishment [5]. It is estimated that
33–50% of all physicians experience at least one of these dimensions of burnout and
that these symptoms are also prevalent among other healthcare workers [5,6]. This is
especially relevant given that work-related stress and symptoms of burnout have been
exacerbated by the COVID-19 pandemic [7]. Multiple studies and organizations have
mobilized to understand and address the issue of physician burnout. In a 2019 study on
the effectiveness of resident-led initiatives, residents reported that they perceived the most
effective interventions to be fitness-based activities (gym, walk, outdoor activity, Tai Chi)
and art therapy. In a meta-analysis of different interventions, a meditation workshop was
also noted to decrease resident burnout rates [8,9]. These findings are highly suggestive
that Forest Bathing, which involves outdoor activity with a mindful meditative component,
could be beneficial in addressing physician burnout.
In a review of the literature, only one study was identified which analyzed the effects
of a Forest Therapy intervention on burnout. A 2015 study held in Korea studied the
effects of a 3-day Forest Therapy program on 19 female “workers in the healthcare and
counseling service industry”, who reported a low-frequency use of a forest environment
compared to a control group of 20 female participants from the same industry who reported
a high-frequency use of a forest environment [10]. The control group was initially found
to have lower indicators of stress than the experimental group, which was thought to
be secondary to them already using the forest environment more frequently prior to the
study. The findings of the study were variable; however, it did find an improvement in
perceived stress levels and on professional efficacy in participants of the Forest Therapy
camp as determined by the Maslach Burnout Inventory (MBI). This study and the lack of
similar studies demonstrates the need for further research of this therapy as a potential
intervention to address the serious and widespread prevalence of physician burnout.
In the United States, the Association of Nature and Forest Therapy (ANFT) is a leading
organization providing Forest Therapy interventions. It offers courses for participants to
become certified Forest Therapy guides, who then lead others through a series of invitations
to encourage a therapeutic, mindful engagement with the natural environment [11]. These
guided walks introduce new practitioners to Forest Therapy who are unfamiliar with this
therapeutic exercise. This has similarities to the Forest Therapy centers in countries such as
Japan, which provide guides, on-site physicians, and designated Forest Bathing trails with
signs listing specific invitations into the practice along the route.
The purpose of this study was to evaluate the effect of a guided Forest Bathing ses-
sion on symptoms of burnout and collect qualitative feedback on this intervention. It was
hypothesized that a Forest Bathing session would result in a statistically significant improve-
ment from baseline burnout symptoms when compared to a control group experiencing a
typical day off of clinical work.
Int. J. Environ. Res. Public Health 2022, 19, 14505
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2. Materials and Methods
2.1. Design
This project was a two-arm, randomized, controlled trial with a waitlist control group.
Outcomes were collected at two timepoints: before and after the allocated intervention.
Participants were allocated into intervention groups by using the randomization module
on REDCap that draws from a pre-randomized table, assigning sequential participant IDs
to different groups. A blinded researcher allocated all new participants at the time they
entered the study by clicking the “randomize” button on the REDCap electronic form.
The randomization table this process drew on was generated before the study by using
blocks of 6 for all possible permutations for 2 groups, and then rolling dice to generate the
sequence of blocks.
The study was conducted according to the guidelines of the Declaration of Helsinki
and approved by the Institutional Review Board of the University of New Mexico Health
Sciences Center (21-419, approved on 1 February 2022. Informed consent was obtained
from all subjects involved in the study before beginning. All recruitment, interventions,
and data collection occurred in a 3-month period in Spring 2022. Participants in the
experimental group were allowed to sign up for a Forest Bathing walk immediately
after filling out the pre-test materials. Participants in the waitlist control group had to
wait a minimum of 5 days and fill out the post-test survey on a day off from clinical
duties before signing up for a Forest Bathing walk. This did not move them into the
experimental group, but rather was carried out solely to allow all interested individuals
to participate in the intervention. This option was made available given that this inter-
vention was being offered to assist with the wellness of healthcare providers coping with
the challenges of a worldwide pandemic.
2.2. Participants and Recruitment
Recruitment used convenience sampling of health sciences faculty and medical resi-
dents at a university/teaching hospital in the southwestern United States. Possible par-
ticipants were contacted through email announcements and in-person presentations on
the physiological and psychological benefits of nature immersion/Forest Bathing. To be
included in the study, participants needed to be: (1) at least 18 years of age, (2) current
faculty of the university’s Health Sciences Center or working as a medical resident at the
teaching hospital, (3) able to physically tolerate a 0.8 km (0.5 mile) walk.
2.3. Interventions
The Forest Bathing walks were conducted through a collaboration with two Forest
Bathing guides who had completed the certification course through the Association of
Nature and Forest Therapy (ANFT). They were hired to be the interveners for the project.
The Forest Bathing walks were initially held at a public open space encompassing ap-
proximately 525 hectares (1300 acres) of mountains and a piñon-juniper forest located
30 min from the university hospital (see Figure 1). The elevation of the intervention area
is approximately 2285 m (7500 feet). The walk began in an open meadow of grama grass
(Bouteloua species) speckled with paintbrush flowers (Castillega species) and overlooked by
several large ponderosa pines (Pinus ponderosa). It then wandered through scattered groves
of one-seed junipers (Juniperus monosperma), pinyon pines (Pinus edulis), and Gambel oak
(Quercus gambelli). The walk concluded at a dramatic rise populated by multiple alligator
junipers (Juniperus deppeana) growing among large boulders, which provided a view of
the forest-covered Sandia mountains. Due to extensive wildfires, public lands were closed
during the period of this study and the final walks were invited to be held on nearby private
land with similar vegetation and terrain. The course of the walk in both locations was less
than 0.8 km (0.5 miles) on a dirt path with some mild variations in grade. Participants were
sent an email with information on the walk as well as suggestions for weather preparedness
(temperatures ranged from approximately 10 degrees Celsius (50 degrees Fahrenheit) in the
mornings of the first walks to 27 degrees Celsius (80 degrees Fahrenheit) in the afternoons
view of the forest-covered Sandia mountains. Due to extensive wildfires, public lands
were closed during the period of this study and the final walks were invited to be held on
nearby private land with similar vegetation and terrain. The course of the walk in both
locations was less than 0.8 km (0.5 miles) on a dirt path with some mild variations in grade.
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burnout can be interpreted in terms of the “identification continuum”, which provides a
dimension ranging from disengagement to dedication, as well as the “energy continuum”,
which provides a dimension ranging from exhaustion to vigor. The OLBI has been proven
effective for both work and academic settings, and for all employees, not just those in
healthcare [13]. It has been found to have a high reliability (Cronbach’s alpha = 0.63), es-
pecially concerning the two dimensions it evaluates: exhaustion (Cronbach’s alpha = 0.87)
and disengagement (Cronbach’s alpha = 0.81) [12].
Int. J. Environ. Res. Public Health 2022, 19, 14505
5 of 11
The Mini-Z is a questionnaire on work-related burnout symptoms, modified from
the MEMO (Minimizing Error Maximizing Outcome) questionnaire, where prior work-
life measures are assessed [14]. The Mini-Z questionnaire includes 10 items that address
job satisfaction, in which participants indicate potential burnout predictors. The Mini-Z
has been evaluated for reliability and validity through the annual administration to all
departments at Hennepin County Medical Center in Minneapolis, MN [15]. Reliability is
reasonable, with Cronbach’s alpha of 0.8 when participants answer using a 1–5 scale within
the range from strongly disagree to strongly agree, respectively (e.g., “I feel a great deal
of stress because of my job”) [16]. Satisfaction and stress are good predictor variables that
correlate with overall burnout (p < 0.001) [17].
2.5. Analysis
Summary statistics were calculated for interventions and controls and compared prior
to analysis using the Wilcoxon rank-sum and Fisher’s exact tests to confirm the groups
were matched demographically.
We analyzed OLBI scores and Mini-Z scores for all individuals in the sample and
standardized the reversed scores on the OLBI questionnaire prior to analysis so that the scale
was consistent for all questions. Scores for the two questionnaires were tested for normality
and homogeneity of variances using the Shapiro–Wilk and Bartlett’s tests, respectively.
After confirming the data normality and homogeneity of variances, we conducted
Student’s t-tests to determine whether baseline and post-test scores differed within the in-
tervention and control groups, and Welch’s t-tests to determine whether baseline scores for
interventions and controls differed from each other and whether the intervention led to signifi-
cantly different post-test scores for the two study groups. We analyzed both the total scores for
each questionnaire, as well as the OLBI disengagement and exhaustion subdomains. p-values
were adjusted for multiplicity using the Benjamini–Hochberg method.
All data were collected and compiled in REDCap before being exported for analyses
in R version 4.1.1.
3. Results
A total of 34 participants were enrolled in the intervention group and a total of
22 participants were enrolled in the control group. During the study, several participants
were lost to follow-up, and as a result, 10 people from the intervention group and
12 people from the control group were excluded. Participants in the intervention and
control groups were matched for age, gender, ethnicity, and race. See Table 1 for complete
demographic data.
The baseline burnout scores of the control and intervention groups from the pre-test
are similar and show no statistical difference between the two groups. Scores from the
OLBI range from 16 to 64. Past studies have a score of 35 or above as a positive indicator of
burnout [18]. The median scores for the pre-tests and post-tests of both the intervention
group and the control group were all above 35 on the OLBI, which is consistent with the
presence of burnout symptoms in these groups. The Mini-Z evaluates burnout as well as
satisfaction and stress, and a total score of 40 or above is defined as a joyful workplace [19].
Neither the pre-test nor post-test median scores for either group reached this threshold
score of 40. Question 2 of the Mini-Z asks the participant to use their own definition of
burnout to choose from five options, and the results can be seen in Figure 2.
When analyzing the data from the OLBI, we did not find a statistically significant
difference between the intervention group and the control group or between the pre-test
and post-test scores for the intervention group (see Table 2). When analyzing the data
from the Mini-Z assessment, there was a slight but statistically significant decrease in the
post-test scores of the intervention group relative to the control group. However, after
adjusting the p-values, this finding was no longer significant. The Mini-Z results similarly
did not demonstrate a significant difference between the pre- and post-test results in either
the intervention or the control group. There was also no significant decrease in post-test
Int. J. Environ. Res. Public Health 2022, 19, 14505
6 of 11
scores for the intervention group relative to the control group for the burnout symptom
subdomains of exhaustion and disengagement on the OLBI (see Table 3).
Table 1. Demographic information.
Cases (n = 34) Controls (n = 22)
p
Test for
Group Comparison
Age in Years: Mean
(Standard Deviation)
40.50 (12.7)
38.73 (8.0)
0.81
Wilcoxon Rank-Sum
n (%)
n (%)
Nonbinary
0 (0.0%)
1 (4.6%)
Gender
Female 27 (79.4%)
19 (86.4%)
Male
7 (20.6%)
0.26
2 (9.1%)
Fisher’s exact
None of these
0 (0.0%)
0 (0.0%)
Hispanic/Latino
Yes
2 (5.9%)
4 (18.2%)
0.20
No 32 (94.1%)
18 (81.8%)
Fisher’s exact
Asian
5 (14.7%)
2 (9.1%)
Black or Af Am
2 (5.9%)
0 (0.0%)
Race
Nat Am
Nat Hawaiian/PI
2 (5.9%)
0 (0.0%)
0 (0.0%)
0 (0.0%)
0.56
Fisher’s exact
White 23 (67.7%)
19 (86.4%)
More than one race
0 (0.0%)
0 (0.0%)
Prefer not to answer
2 (5.9%)
1 (4.6%)
Notes: Participant 55 does not have a group number, so is excluded from the table; participant 24 (case group) chose
Race 3 and Race 5)
Age breakdown
Full Sample
Cases
Controls
Mean Age
39.8
40.5
38.7
Minimum Age
26
26
28
Maximum Age
69
69
65
Sample Size by Age Range
n (%)
n (%)
n (%)
Total
57 (100.0%)
35 (100.0%)
22 (100.0%)
Age 20–29
8 (14.0%)
7 (20.6%)
1 (4.6%)
Age 30–39
23 (40.4%)
12 (35.3%)
10 (45.5%)
Age 40–49
18 (31.6%)
8 (23.5%)
10 (45.5%)
Age 50–49
3 (5.3%)
3 (8.8%)
0 (0.00%)
Age 60–69
5 (8.8%)
4 (11.8%)
1 (4.6%)
Participant 65 is missing age (case group)
Table 2. Pre- and post-test analysis of Oldenburg Burnout Inventory and Mini-Z assessments.
Oldenburg Burnout Inventory Overall Scores (Cases vs. Controls)
Cases
Controls
Test
pre-Test Median score
39.00
42.00
Wilcoxon rank-sum test
post-test median score
38.00
41.00
Wilcoxon rank-sum test
Notes: Reversed scores were recoded prior to analysis.
p-Value
0.07
0.17
adj p-Value
ns
ns
Int. J. Environ. Res. Public Health 2022, 19, 14505
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Table 2. Cont.
Mini-Z Scores (Cases vs. Controls)
Cases
Controls
Test
p-Value
adj p-Value
pre-test median score
35.00
36.00
Wilcoxon rank-sum test 0.21
ns
post-test median score
34.00
37.00
Wilcoxon rank-sum test 0.03
ns
Significant results are highlighted in red (raw p = 0.05 was used as the threshold for significance).
Oldenburg Burnout Inventory Overall Scores (Change in Scores within Groups)
Pre-Test
Median Score
Post-Test
Median Score
Test
p-Value
adj p-Value
cases (n = 24)
paired t-test
controls (n = 10)
paired t-test
cases (n = 24)
39.50
38.00
Wilcoxon signed-rank test 0.30
ns
controls (n = 10)
41.50
41.00
Wilcoxon signed-rank test 0.44
ns
Notes: Ten cases and twelve controls had pre-test scores, but not post-test scores; one case had a post-test score, but no pre-test
score; these participants were excluded from the paired analyses. Reversed scores were recoded prior to analysis.
Mini-Z Scores (Change in Scores within Groups)
Pre-Test
Median Score
Post-Test
Median Score
Test
p-Value
adj p-Value
cases (n = 24)
33.63
33.92
paired t-test
0.43
0.43
controls (n = 10)
36.10
36.90
paired t-test
0.27
0.27
cases (n = 24)
34.00
34.00
Wilcoxon signed-rank test 0.23
ns
controls (n = 10)
37.00
37.00
Wilcoxon signed-rank test 0.31
ns
Int. J. ENnvoitreosn: .TRenesc.aPsuesblainc dHtewaletlhv2e0c2o2n,tr1o9l,sxhFadOpRreP-EteEsRt sRcoErVesI,EbWut not post-test scores; one case had a post-test score, but no pre-test
score; these participants were excluded from the paired analyses.
FFigiguruer2e. 2R.eRsueltssuflrtosmfraollmpaartlilcipparntiscoipnaMnitnsi-oZnQMueisntiio-nZ2Qcounecsetrinoinng2bucornnocuetrsnyimnpgtobmusr.nout symptom
4. Discussion
The aim of this study was to assess the impact of participating in a Shinr
intervention on the level of burnout of physicians and other healthcare workers. F
that would have clearly demonstrated that this therapy can decrease burnout sy
would have shown a significant decrease in burnout scores on the post-test relati
pre-test in the intervention group on either the OLBI or the Mini-Z tests, or a sig
Int. J. Environ. Res. Public Health 2022, 19, 14505
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Table 3. Analysis of Oldenburg Burnout Inventory Subdomains.
Oldenburg Burnout Inventory Subscores (Cases vs. Controls)
Cases
Controls
Test
p-Value
Disengagement
pre-test median score
18.00
20.00
Wilcoxon rank-sum test 0.07
post-test median score
18.00
20.00
Wilcoxon rank-sum test 0.30
Exhaustion
pre-test median score
20.50
22.00
Wilcoxon rank-sum test 0.10
post-test median score
20.00
21.50
Wilcoxon rank-sum test 0.04
Notes: Reversed scores were recoded prior to analysis. Significant results are highlighted in red
(raw p = 0.05 was used as the threshold for significance).
Oldenburg Burnout Inventory Subscores (Change in Scores within Groups)
Pre-Test
Median Score
Post-Test
Median Score
Test
p-Value
Disengagement
cases (n = 24)
19.00
18.50
Wilcoxon rank-sum test 0.33
controls (n = 10)
20.00
20.00
Wilcoxon rank-sum test 0.88
Exhaustion
cases (n = 24)
20.00
20.00
Wilcoxon signed-rank test 0.34
controls (n = 10)
21.50
21.50
Wilcoxon signed-rank test 0.16
Notes: Ten cases and twelve controls had pre-test scores, but not post-test scores; one case had a post-test score,
but no pre-test score; these participants were excluded from the paired analyses. Reversed scores were recoded
prior to analysis.
adj p-Value
ns
ns
ns
ns
adj p-Value
ns
ns
ns
ns
4. Discussion
The aim of this study was to assess the impact of participating in a Shinrin-Yoku
intervention on the level of burnout of physicians and other healthcare workers. Findings
that would have clearly demonstrated that this therapy can decrease burnout symptoms
would have shown a significant decrease in burnout scores on the post-test relative to the
pre-test in the intervention group on either the OLBI or the Mini-Z tests, or a significant
decrease in the burnout scores on the post-test for the intervention group relative to the
control group. The latter was initially detected for the Mini-Z test alone, although this
finding was then negated when the p-value was adjusted. This result may, in part, be due
to a loss of power in the context of a smaller sample size. Although the results from the
Mini-Z test are suggestive that the intervention decreased aspects of burnout, it would
require further studies with a larger sample size to better determine this. Overall, the
results from this study do not demonstrate a significant impact on burnout scores from
these two tools, resulting from a Forest Bathing intervention.
The data add to the body of evidence that burnout symptoms are prevalent among
healthcare providers. The median scores from the OLBI are consistent with burnout
symptoms in both the intervention group and the control group. On question 2 of the
Mini-Z test, 34% of participants reported some symptoms of burnout. This includes 12%
who reported persistent burnout symptoms that do not go away.
The post-intervention data also gathered subjective comments on the mental state of
the Shinrin-Yoku participants. Twenty participants responded with comments. Nineteen of
these comments focused on feeling more relaxed, more peaceful, calmer, more appreciative,
and less anxious. Only one comment stated that they did not detect a difference in their
internal state after the walk.
These results that do not demonstrate a significant difference in burnout scores after
a Shinrin-Yoku intervention appear to be in contradiction to these subjective comments
Int. J. Environ. Res. Public Health 2022, 19, 14505
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which report the psychologically calming benefits of this therapy. These findings also
appear in contradiction to the results from other studies that showed participating in
Shinrin-Yoku can alleviate symptoms of depression, anxiety, and stress, which are all
connected to symptoms of burnout [2]. This then raises the question of the nature of
healthcare worker burnout and how it is fundamentally different from either a state of
mood or a psychiatric disorder. It can be described as a reactive syndrome that develops
over a prolonged period due to systemic issues, bureaucratic burdens, and repetitive moral
injury. One of the participants of this study put this succinctly when they wrote, “I felt very
relaxed after forest therapy. Then I came home and did 6 h of work that needed to be done
before Monday, and then took the survey. I generally feel stressed on Sunday afternoons
trying to finish all the things that didn’t get done during the week and forest therapy didn’t
take those things away.” It is likely that, for some, their experience of a Shinrin-Yoku walk
highlighted rather than relieved their sources of burnout symptoms. It is also of note that
recruitment was a significant challenge for this study, not due to a lack of interest, but rather
due to difficulties for many interested physicians in finding sufficient time off from their
clinical duties to join a Shinrin-Yoku walk. This represented an insurmountable obstacle
for many of the 79 people who originally signed up as interested in the study. As one
participant wrote after their Shinrin-Yoku walk, they were “more aware of how exhausted I
am, the degree of anxiety I carry around. I also felt more at peace and like I might be able to
tolerate the intense 120+ hour schedule I have for the next 2 weeks”. This articulates both
the challenge in addressing the source of burnout symptoms and the need for interventions
such as Shinrin-Yoku for providing the subjective sense of peace that is so often lacking
in healthcare. It is clear from the subjective responses that many of the participants on
these Shinrin-Yoku walks found them to be of value to their mental wellbeing despite not
significantly impacting their burnout symptoms.
When considering why the study participants reported feelings of “peace” that did not
translate to decreased burnout scores, it is important to note that Shinrin-Yoku is often pro-
posed to be an ongoing practice rather than a one-time intervention [20]. The distinguished
Japanese researchers of this therapy, Dr Yoshifumi Miyazaki and Dr Qing Li, as well as
Amos Clifford, the founder of the Association of Nature and Forest Therapy, propose that
Shinrin-Yoku be incorporated into the participant’s life as an ongoing practice [11,20]. In a
way similar to psychotherapy, yoga, and tai chi, it is understandable that a single session
of Shinrin-Yoku would not produce a measurable improvement in a chronic condition,
such as healthcare worker burnout. This, as well as the small sample size, were significant
limitations for this study which introduced this therapy to dozens of healthcare workers,
but did not assess the long-term impact of using this therapy over months and years on
burnout symptoms.
5. Conclusions
In conclusion, the data from this randomized controlled trial did not demonstrate
a change in burnout symptoms from participating in a single Shinrin-Yoku walk when
compared to baseline burnout scores or when compared to a control group. This does not
mean, however, that there is no possible role for Forest Therapy in providing relief from
burnout symptoms. The subjective comments from participants after the Shinrin-Yoku
walk are consistent with many previous studies which demonstrated the ability of this
practice to decrease stress and anxiety [2]. It is unlikely that anyone can experience burnout
without simultaneously experiencing stress and anxiety. Burnout symptoms accumulate
over time, and thus, it is reasonable to suppose that alleviating burnout will also take
time. An ongoing practice of Forest Therapy may very well erode the severity of burnout
symptoms through cumulative improvements in stress and anxiety levels. Therefore, there
is a need for further research on the impact of Shinrin-Yoku on burnout symptoms in
healthcare workers over a prolonged period and as a regular practice.
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Author Contributions: J.K., H.H.R. and M.E.H. All contributed to the conceptualization, methodol-
ogy, investigation, resources, original draft preparation, review and editing, visualization, supervision,
and funding acquisition. C.W. contributed to the investigation and draft review and editing. J.G. con-
tributed to the software, validation, formal analysis, and data curation. All authors have read and
agreed to the published version of the manuscript.
Funding: This project was funded by an internal grant from the University of New Mexico Faculty
Lifecycle Scholarship Fund by the Office of Faculty Affairs and Career Development.
Institutional Review Board Statement: The study was conducted according to the guidelines of the
Declaration of Helsinki, and approved by the Institutional Review Board of the University of New
Mexico Health Sciences Center (21-419, approved on 2/1/22).
Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.
Data Availability Statement: Raw data can be obtained by contacting the primary author. All data
will be de-identified to protect participant privacy.
Acknowledgments: The authors would like to acknowledge and express gratitude to Elizabeth
Lawrence, Akshay Sood, and the University of New Mexico faculty, residents, and staff who provided
support for the study; the city of Albuquerque Open Space Division, Leila Von Stein, and the Blue
Desert Retreat Center for providing the maintained trails we used for the Shinrin-Yoku walks; and
our amazing Forest Therapy guides, Sally Stevens and Alix Peters.
Conflicts of Interest: The authors declare no conflict of interest.
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