Effect of Nature Walks on Depression and Anxiety: A Systematic Review

Round 1

Reviewer 1 Report

The paper contain significant information. There is growing interest in the potential for nature-based activities to provide therapeutic  benefits. Nature-based interventions such as forest bathing are potentially cost-effective treatments that can provide multiple benefits and are potentially accessible to a range of people. Shinrin-yoku, or forest bathing, is a practice originating in Japan and now followed globally. There are many articles in which this topic is discussed.

In my opinion, the keywords do not seem to match well. I’m surprised that the authors used  "shinrin-yoku" and "swimming in the forest" as keywords. Because in the further part of the research, the authors ignore ". Shinrin-yoku "or" forest bathing when they are searching databases (why? it is not clear to me ).

I don’t understand, why  the authors chose retrieved with search terms as “nature” AND “walk” a they rejected term” forest “and “walk”. This is  my main concern with this paper.  Adding these entries in research databases, would increase the number of articles found. .

Authors give, that articles were excluded if they included other nature-based interventions (e.g., shinrin-yoku), despite this, later  5 articles were in a forest or woodland. This is for me not incomprehensible.

I have below comments for authors:

Lines:. 99-101 and 108-109- the aims of the work were repeated

In methods, it is not necessary to specify who what exactly what did. The reader is not interested in the division of the co - authors' work. This should be given in Author Contributions.

Author Response

Thank you for your helpful feedback. We have systematically revised our manuscript addressing the points you have raised (red texts in the manuscrip). We hope this revised paper is now acceptable for publication. We extend our sincere gratitude to you for your feedback that has significantly helped to strengthen the paper.

Reviewer 1’s comment 1 (1-1)
The paper contain significant information. There is growing interest in the potential for nature-based activities to provide therapeutic  benefits. Nature-based interventions such as forest bathing are potentially cost-effective treatments that can provide multiple benefits and are potentially accessible to a range of people. Shinrin-yoku, or forest bathing, is a practice originating in Japan and now followed globally. There are many articles in which this topic is discussed.
In my opinion, the keywords do not seem to match well. I’m surprised that the authors used  "shinrin-yoku" and "swimming in the forest" as keywords. Because in the further part of the research, the authors ignore ". Shinrin-yoku "or" forest bathing when they are searching databases (why? it is not clear to me ).
 
Authors’ response 1-1
Thank you for your helpful feedback. In line with your comment, now the keyword “shinrin-yoku” is replaced with “nature walk”. We did not put “swimming in the forest” as a keyword.Now the keywords are: nature walk; state anxiety; PRISMA; nature-based intervention; review work. 
 

Reviewer 1’s comment 2 (1-2)
I don’t understand, why  the authors chose retrieved with search terms as “nature” AND “walk” a they rejected term” forest “and “walk”. This is  my main concern with this paper.  Adding these entries in research databases, would increase the number of articles found. .
Authors give, that articles were excluded if they included other nature-based interventions (e.g., shinrin-yoku), despite this, later  5 articles were in a forest or woodland. This is for me not incomprehensible.
 
Authors’ response 1-2
Thank you for your helpful suggestion. We added the term “forest” and identified 4 additional studies to be included. We also searched other terms such as grassland”, “coastal”, “greenspace” and “woodland”, however no eligible studies were identified. The whole paper was revised accordingly. 
 
 
Reviewer 1’s comment 3 (1-3)
I have below comments for authors:
Lines:. 99-101 and 108-109- the aims of the work were repeated
 
Authors’ response 1-3
In line with your comment, Lines 99-101 are now removed. 
 
 
Reviewer 1’s comment 4 (1-4)
In methods, it is not necessary to specify who what exactly what did. The reader is not interested in the division of the co - authors' work. This should be given in Author Contributions.
 
Authors’ response 1-4
Thank you for your helpful comment. We followed the current guidelines for systematic review, which recommend identifying who did what in the analysis (Cooper et al., 2018), therefore we would like to retmain those in the manuscript as well. This reference is now added to the paper. 
 
Cooper, C., Booth, A., Varley-Campbell, J. et al. Defining the process to literature searching in systematic reviews: a literature review of guidance and supporting studies. BMC Med Res Methodol 18, 85 (2018). https://doi.org/10.1186/s12874-018-0545-3

Reviewer 2 Report

Comments on Sustainability Article

1. Why are keywords out of place? Please fix
2. P. 2. So far there is a tendency to weave forest bathing into everything. Is this a manuscript about primarily forest bathing. If so, it should be in the title.
3. l. 42-43, needs a seque linking the two paragraphs.
4. L. 57, pretty broad statement, needs a citation.
5. L.89. You need to define what you mean by nature walks, and provide some parameters such as where, when, how long, with who, what type of nature, etc.
6. L.219, Attention Restoration Theory mainly focused on attention and to a lesser extent, stress but to my knowledge did not specifically address the issue of anxiety. Please address this issue.
7. You might have discovered more data by looking at stress rather than depression and anxiety.
8. L. 262. There have been studies done on type of nature which should be looked at.
9. L. 273. Please fix sentence structure.
10. L. 290. RCT = Random Control Treatments?? Please define
11. L 306. Good point!

Author Response

Thank you for your helpful feedback. We have systematically revised our manuscript addressing the points you have raised (red texts in the manuscript). We hope this revised paper is now acceptable for publication. We extend our sincere gratitude to you for your feedback that has significantly helped to strengthen the paper.

Reviewer 2’s comment 1 (2-1)
Why are keywords out of place? Please fix
 
Authors’ response 2-1
Keywords are placed following the template (L25). Thank you.
 
 
Reviewer 2’s comment 2 (2-2)
P. 2. So far there is a tendency to weave forest bathing into everything. Is this a manuscript about primarily forest bathing. If so, it should be in the title.
 
Authors’ response 2-2
In line with your comment, now statements about forest bathing are removed as that blurred the focus of this paper. More emphasis on the nature-based approaches is now added, as well as the feasibility and accessibility of nature walk. 
 
 
Reviewer 2’s comment 3 (2-3)
l. 42-43, needs a seque linking the two paragraphs.
 
Authors’ response 2-3
In line with your comment, now the last sentence of the first paragraph is removed, and the second paragraph was merged into the first paragraph to give a stronger flow. 

Reviewer 2’s comment 4 (2-4)
L. 57, pretty broad statement, needs a citation.
 
Authors’ response 2-4
Thank you for your suggestion. Now 2 references are provided there.
K. McEwan et al., “A Pragmatic Controlled Trial of Forest Bathing Compared with Compassionate Mind Training in the UK: Impacts on Self-Reported Wellbeing and Heart Rate Variability,” Sustainability, vol. 13, no. 3, p. 1380, Jan. 2021, doi: 10.3390/su13031380.
M. M. Hansen, R. Jones, and K. Tocchini, “Shinrin-Yoku (Forest Bathing) and Nature Therapy: A State-of-the-Art Review.,” Int. J. Environ. Res. Public Health, vol. 14, no. 8, 2017, doi: 10.3390/ijerph14080851.
 
 
Reviewer 2’s comment 5 (2-5)
L.89. You need to define what you mean by nature walks, and provide some parameters such as where, when, how long, with who, what type of nature, etc.
 
Authors’ response 2-5
In line with your comment, now the definition and description of nature walks are added.
 

Reviewer 2’s comment 6 (2-6)
L.219, Attention Restoration Theory mainly focused on attention and to a lesser extent, stress but to my knowledge did not specifically address the issue of anxiety. Please address this issue.
You might have discovered more data by looking at stress rather than depression and anxiety.
 
Authors’ response 2-6
Thank you for pointing this out. The soothing effects of phytoncides (antimicrobial organic compound released from plants) are more appropriate to explain our results (i.e., consistent effects on state anxiety) than Attention Restoration Theory, therefore revised accordingly. Phytoncides are more related to anxiety than depression. 
 
 
Reviewer 2’s comment 7 (2-7)
L. 262. There have been studies done on type of nature which should be looked at.
 
Authors’ response 2-7
In line with your comment, the need for evaluating the type of nature is noted in the discussion section (L.642-645) and Appendix A. 
 

Reviewer 2’s comment 8 (2-8)
L. 273. Please fix sentence structure.
L. 290. RCT = Random Control Treatments?? Please define
L 306. Good point!
 
Authors’ response 2-8
Now the whole manuscript has been proofread by each co-author to address those points. Thank you for your helpful feedback. 

Round 2

Reviewer 2 Report

Comments on Sustainability Article (Revised Version)

1. Wording seems missing around l. 38-39.
2. L. 92-98, English structure seems to be insufficient at times. Please check and fix

Author Response

Thank you again for your helpful comments. In line with your comments, those 2 parts are now revised. 

Commet 1

"... activity including walking in nature. Nature-based interventions are potentially cost-effective treatments [6] that can provide multiple benefits [7] and are potentially accessible to a range of people providing there is adequate provision of public greenspace [8]. "

Comment 2

"Here, we systematically reviewed the literature for evidence of the effect of nature walks on anxiety and depression outcomes. Nature walks are walks on a trail in a natural setting such as forests, woodlands or parks [30] that can take any time from 15 minutes [31] to a few hours [32]. Nature walks can be undertaken by diverse populations (e.g., cancer survivors [32], university students [33]), and conducted in any season of the year [34][31]. We focused on nature walks as an example of a nature-based therapy, because they are simple and low-risk to undertake, and potentially accessible to many people [35][36]. As these practical aspects are crucial in the delivery of treatment, the mental health effect of nature walks was chosen to be evaluated in this review"