Restorative potential of different noise-exposed natural and urban environments

ISRCTN ISRCTN48943261
DOI https://doi.org/10.1186/ISRCTN48943261
Secondary identifying numbers 193847
Submission date
23/11/2023
Registration date
24/11/2023
Last edited
03/07/2024
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Mental and Behavioural Disorders
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English summary of protocol

Background and study aims
Life is very stressful for many people nowadays. One possibility to restore and to reduce stress could be spending time in natural environments. Earlier studies have compared whether people restore more when they go for a walk in an urban or a natural environment. Most of these previous studies do not consider that urban environments are not only less green than natural environments, but typically also feature increased levels of noise. So, the benefits of exposure to natural compared to urban environments reported in earlier studies might be less due to “greenness” of the natural environment than to additional stressors like traffic noise in the urban environment. The aim of this study is to examine whether people restore more when walking in natural than in urban environments, taking the road traffic noise exposure during the walks in the respective settings into account. In addition to investigating how much people restore, depending on where they go for a walk (urban or natural environment), the study also investigates the effects of how individuals go for a walk and which inner attitude they adopt while walking. Thus, the study also examines whether helping people to be more mindful while walking in natural environments may increase the potential positive effects of walking in natural environments.

Who can participate?
Healthy individuals aged 18 years or older

What does the study involve?
Participants will go for a guided group walk along a predetermined route for 30 minutes in the city of Zürich, Switzerland. Participants will walk in either an urban environment with high traffic noise, an urban environment with low traffic noise, a forest with high traffic noise, a forest with low traffic noise or a forest with low traffic noise in which participants walk with a mindfulness intervention. Participants will answer a questionnaire before and after the walk, they will do an attention test and physiological stress will be assessed via salivary cortisol levels and skin conductance.

What are the possible benefits and risks of participating?
Participants may benefit from reduced stress and restoration. The level of potential risk is judged to be minimal. A possible risk is irritation of the skin from detaching the two electrodes that were put on one of their hands to measure skin conductance during the walk.

Where is the study run from?
Swiss Federal Institute for Forest, Snow and Landscape Research WSL (Switzerland)

When is the study starting and how long is it expected to run for?
November 2020 to June 2024

Who is funding the study?
Swiss National Science Foundation (Switzerland)

Who is the main contact?
Julia Schaupp, julia.schaupp@wsl.ch

Contact information

Mrs Julia Schaupp
Public, Scientific, Principal Investigator

Zürcherstr. 111
Birmensdorf
8903
Switzerland

ORCiD logoORCID ID 0000-0001-9098-6608
Phone +41 (0)447392484
Email julia.schaupp@wsl.ch

Study information

Study designRandomized controlled intervention study
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Built environment/local authority, Other
Study typePrevention
Participant information sheet Not available in web format, please use contact details to request a participant information sheet
Scientific titlePsycho-physiological effects of walking in different noise-exposed natural and urban environments with or without mindfulness intervention
Study acronymJS
Study objectives1. Walking in forest settings, compared to walking in urban settings, leads to a stronger increase in stress reduction, restoration, positive affect, attention, nature connectedness and rumination, as well as a stronger decrease in negative affect.
2. Walking in environments with low traffic noise, compared to walking in environments with high traffic noise, leads to a stronger increase in stress reduction, restoration, positive affect, attention, nature connectedness, and rumination, as well as a stronger decrease in negative affect.
3. Walking in forests with low traffic noise, compared to walking in forests with high traffic noise, leads to a stronger increase in stress reduction, restoration, positive affect, attention, nature connectedness and rumination, as well as a stronger decrease in negative affect.
4. Walking in urban environments with low traffic noise, compared with walking in urban environments with high traffic noise, leads to a stronger increase in stress reduction, restoration, positive affect, attention, nature connectedness and rumination, as well as a stronger decrease in negative affect.
5. Walking in forest settings with a mindfulness intervention, compared to walking in forest settings without a mindfulness intervention, leads to a stronger increase in stress reduction, restoration, positive affect, attention, nature connectedness, and rumination, as well as a stronger decrease in negative affect.
Ethics approval(s)

Approved 27/01/2022, Ethics Committee of the Swiss Federal Institute of Technology Zurich (Rämistrasse 101, Zürich, 8092, Switzerland; +41 (0)44 632 85 72; ethics@sl.ethz.ch), ref: EK 2021-N-211

Health condition(s) or problem(s) studiedStress reduction, restoration and fostering of wellbeing in healthy individuals
InterventionIntervention study, employing a pretest-posttest design, to compare the effects of 30-minute walks in natural or urban environments with different road traffic noise levels and with or without a mindfulness intervention. Individuals will be asked to go for a guided group walk with a maximum of six participants. Participants will be randomly assigned to one of the following conditions: urban environment with high traffic noise, urban environment with low traffic noise, forest with high traffic noise, forest with low traffic noise. A fifth condition will consist of a walk in a forest with low traffic noise, in which participants walk with a mindfulness intervention. Data will be assessed before (t1) and directly after (t2) the walk. After this, participants will be instructed to walk individually for three times during the next ten days. Ten days after participating in the field experiment, participants will receive an invitation to respond to a third questionnaire (t3).

The study employs a between-subject design and participants will be randomly allocated to one of the study conditions by the random generator of the online survey tool SoSci Survey.
Intervention typeBehavioural
Primary outcome measure1. Perceived restoration following the walk, measured by a slightly modified version of the restoration outcome scale (ROS) after the walk on site and 10 days afterwards
2. Physiological stress, measured by assessing participants’ salivary cortisol as a physiological stress marker at three points: directly after participants arrive at the test site, right before the walk starts, and directly after the walk on site.
Secondary outcome measures1. Positive and negative affect is assessed using the Positive and Negative Affect Schedule (PANAS) questionnaire before and after the walk on site.
2. The perceived restorative quality of the environments examined in this study is assessed by the Perceived Restorativeness Scale-11 after the walk on site and 10 days afterwards
3. Rumination is assessed with the German version of the Perseverative Thinking Questionnaire (PTQ) before and after the walk on site and 10 days afterwards
4. Nature connectedness is measured with the short-form Nature Relatedness Scale (NR-6) and the Love and Care for Nature Scale (LCS) before the walk on site, after the walk on site and 10 days afterwards
5. Noise annoyance is assessed with the 11-point ICBEN (International Commission on Biological Effects of Noise) scale after the walk on site.
6. Participants’ individual experience of soundscape during the walk is assessed in accordance with the ISO/TS 12913-2 (International Organization for Standardization, 2018) after the walk on site
7. Life satisfaction is measured with the German General Life Satisfaction Short Scale (L-1) before and after the walk on site, and 10 days afterwards
8. Noise sensitivity is assessed with one item, asking participants how strongly they agree with the statement “I am noise sensitive”. The item is rated on a 5-point rating scale ranging from 1 (do not agree at all) to 5 (agree very much). Noise sensitivity is assessed after the walk on site.
9. State mindfulness is assessed with the State Mindfulness Scale before and after the walk on site
10. Trait mindfulness is assessed with the short form of the Kentucky Inventory of Mindfulness Skills before the walk on site and 10 days afterwards
11. Skin conductance level is measured continuously throughout the walk on site via electrodermal activity sensors (Shimmer3 GSR+ sensor, Simmer sensing, Dublin, Ireland), reflecting physiological arousal.
12. Attention is assessed with the Necker Cube Pattern Control Test before and after the walk on site with a cognitive test
13. Noise is assessed with continuous audio recordings using a free-field measurement microphone during the walks
Overall study start date01/11/2020
Completion date07/06/2024

Eligibility

Participant type(s)Healthy volunteer
Age groupAdult
Lower age limit18 Years
SexBoth
Target number of participants400
Total final enrolment526
Key inclusion criteria1. Aged 18 years and older
2. Physically able to walk for half an hour at a moderate pace
3. Have no diagnosed hearing problems
4. Do not take cortisone for medical reasons
5. BMI <35 kg/m²
Key exclusion criteria1. Younger than 18 years
2. Diagnosed hearing problems
3. Take cortisone for medical reasons
4. BMI >35 kg/m²
Date of first enrolment16/05/2022
Date of final enrolment06/06/2024

Locations

Countries of recruitment

  • Switzerland

Study participating centre

Swiss Federal Institute for Forest Snow and Landscape Research WSL
Zürcherstr. 111
Birmensdorf
8903
Switzerland

Sponsor information

Swiss Federal Institute for Forest, Snow and Landscape Research
Research organisation

Zürcherstr. 111
Birmensdorf
8903
Switzerland

Phone +41 (0)44 739 21 11
Email wslinfo@wsl.ch
Website https://www.wsl.ch/en/index.html
ROR logo "ROR" https://ror.org/04bs5yc70

Funders

Funder type

Research organisation

Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
Private sector organisation / Trusts, charities, foundations (both public and private)
Alternative name(s)
Schweizerischer Nationalfonds, Swiss National Science Foundation, Fonds National Suisse de la Recherche Scientifique, Fondo Nazionale Svizzero per la Ricerca Scientifica, Fonds National Suisse, Fondo Nazionale Svizzero, Schweizerische Nationalfonds, SNF, SNSF, FNS
Location
Switzerland

Results and Publications

Intention to publish date30/11/2025
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryData sharing statement to be made available at a later date
Publication and dissemination planPlanned publication in a high-impact peer-reviewed journal.
IPD sharing planThe data-sharing plans for the current study are unknown and will be made available at a later date.

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Protocol article 06/05/2024 08/05/2024 Yes No

Editorial Notes

03/07/2024: The following changes were made to the study record:
1. The recruitment end date was changed from 01/07/2024 to 06/06/2024.
2. The overall study end date was changed from 31/10/2024 to 07/06/2024.
3. Total final enrolment added.
08/05/2024: Publication reference added.
24/11/2023: Study's existence confirmed by the Ethics Committee of the Swiss Federal Institute of Technology Zurich.