Shinrin Yoku Journal 2024-06-EN-6
ISBN: 978-83-68042-14-6

Introduction

The systematic review by Wen et al. (2019) investigates the health benefits of forest bathing (Shinrin-yoku) and evaluates the methodological quality of the studies involved. Forest bathing, a practice originated in Japan, involves immersing oneself in a forest environment using all five senses to promote physical and psychological health. This review aims to provide scientific guidance for the integration of forestry and medicine.

Methods

• Study Selection: The review included studies published between January 1, 2015, and April 1, 2019, sourced from PubMed, Embase, and Cochrane Library. A total of 210 papers were initially retrieved, and 28 met the inclusion criteria.
• Quality Assessment: The Downs and Black checklist was used to evaluate the methodological quality of both randomized controlled trials (RCTs) and non-randomized controlled trials (NRCTs).

Results

• General Findings: Forest bathing activities have been shown to significantly improve cardiovascular function, neuroendocrine function, metabolic function, immunity, and psychological well-being.
• Methodological Quality: RCTs demonstrated higher methodological quality compared to NRCTs (p < 0.05).
• Health Benefits:
  • Cardiovascular: Significant reductions in blood pressure and improvements in heart rate variability were reported.
  • Neuroendocrine: Decreases in cortisol, adrenaline, and other stress-related hormones were observed.
  • Metabolic: Improvements in triglyceride levels and increases in adiponectin were noted.
  • Immune Function: Enhanced activity of natural killer cells and other immune markers.
  • Psychological: Improvements in mood, reductions in anxiety and depression, and overall enhanced emotional well-being.

Discussion

• Subhealth Symptoms: Forest bathing addresses subhealth symptoms such as fatigue, poor sleep quality, and chronic pain, which are prevalent due to modern urban lifestyles.
• Empirical Evidence: Despite the promising findings, there is a need for more high-quality, diverse studies to fully understand the mechanisms and benefits of forest bathing.
• Interdisciplinary Approach: The review highlights the importance of interdisciplinary research combining forestry and medical sciences to develop a comprehensive understanding of forest bathing’s health benefits.

Practical Implications for Shinrin Yoku Guides 

The systematic review by Wen et al. (2019) provides several insights and practical implications for Shinrin Yoku guides to effectively facilitate forest bathing sessions:

1. Session Structure and Duration

• Short-term and Long-term Sessions: The majority of studies included sessions lasting between 1 to 3 days, while some lasted longer. Shorter sessions can still be beneficial but consider extending the duration for more profound effects.
• Activity Variety: Include a mix of walking, sitting, and light exercises to engage participants fully with the forest environment.

2. Enhancing the Five Senses Experience

• Vision: Encourage participants to observe different elements of the forest, such as the colors of the foliage and the movement of wildlife.
• Smell: Suggest participants close their eyes and focus on the various forest scents, which can enhance relaxation and reduce stress.
• Hearing: Guide participants to listen attentively to natural sounds, which can improve mood and reduce anxiety.
• Touch: Incorporate activities that involve touching natural elements like tree bark and leaves to increase sensory engagement.
• Taste: If appropriate, include tasting sessions with safe, edible forest products to deepen the sensory experience.

3. Psychological and Emotional Well-being

• Mindfulness and Meditation: Integrate mindfulness exercises and meditation, as they are shown to improve emotional states and reduce stress levels.
• Journaling and Reflection: Encourage participants to keep a journal to record their thoughts and feelings during the session, promoting self-reflection and emotional processing.

4. Health Monitoring

• Pre and Post Measures: If possible, measure physiological markers such as blood pressure and heart rate before and after the session to monitor health improvements.
• Self-reported Measures: Use validated self-reported scales to assess participants’ mood and stress levels, both before and after the sessions.
• Psychological Risk Assessment: Use a Psychological  Risk Assessment approach by Shinrin Yoku Association (Guziak, 2023)

5. Safety and Group Dynamics

• Group Size: Keep the group sizes manageable to ensure individual attention and to foster a more intimate connection with nature.
• Safety Precautions: Conduct a thorough safety briefing at the beginning of each session, covering potential hazards and safety measures in the forest environment.
• Adaptability: Be prepared to adjust activities based on weather conditions and the physical abilities of participants to ensure safety and comfort.

6. Evidence-based Interventions

• Cardiovascular and Neuroendocrine Health: Highlight the benefits of forest bathing on cardiovascular health (e.g., reduced blood pressure and heart rate) and stress hormone levels (e.g., reduced cortisol), as these are significant findings from the review.
• Immune Function: Emphasize activities that can boost immune function, such as walking and breathing exercises, which have been shown to increase natural killer cell activity.
• Mental Health: Focus on reducing anxiety and depression through immersive nature experiences, leveraging the calming effects of the forest environment.

7. Shinrin Yoku Invitations

• Invitation to Connect: Start with invitations that encourage participants to connect deeply with the forest, such as “Take a few moments to become aware of your surroundings. Notice the details in the leaves and the texture of the bark.”
• Invitation to Wander: Suggest exploring without a specific goal, like “Wander slowly through the forest, letting your curiosity guide you.”
• Invitation to Sit: Find spots for participants to sit quietly and absorb the environment, saying “Find a comfortable place to sit and simply be present. Notice the sounds and the rhythm of your breath.”
• Invitation to Breathe: Incorporate breathing exercises, like “Take slow, deep breaths. Feel the fresh forest air fill your lungs and exhale any tension.”
• Invitation to Reflect: Encourage reflection with prompts such as “Reflect on your experience. How do you feel now compared to when you arrived?”

For more detailed information, you can refer to the full article: Wen et al. (2019).