Anxiety and chronic stress are among the most common concerns people bring into therapy. Symptoms like racing thoughts, muscle tension, difficulty sleeping, and restlessness are often linked to an overactive nervous system. While traditional therapy offers many effective tools an often-overlooked ally in this healing process is the natural world. Nature-based therapy provides a unique way to calm the body and mind by directly engaging the nervous system. Ready for a high school biology review?
The Nervous System and Anxiety
The autonomic nervous system has two primary branches: the sympathetic nervous system (responsible for the “fight or flight” responses) and the parasympathetic nervous system (responsible for the “rest and digest” states). When someone lives with chronic anxiety or stress, the sympathetic system tends to dominate, flooding the body with cortisol and adrenaline. Over time, this imbalance can leave people feeling stuck in hypervigilance or burnout.
Polyvagal Theory, developed by Stepen Porges (2011), adds another layer of understanding by describing how cues of safety or danger shift the nervous system between states of connection, mobilization, and shutdown. To restore balance, we need environments and practices that signal safety to the nervous system. This is where nature plays an invaluable role.
Nature as a Regulator of Stress Responses
A growing body of research shows that spending time outdoors directly reduces markers of stress.
*Lower Cortisol Levels: Studies demonstrate the time in green spaces reduces cortisol, the body’s primary stress hormone (Hunter et al., 2019).
*Heart Rate and Blood Pressure: Exposure to natural settings lowers heart rate and blood pressure compared to urban environments (Park et al, 2910).
*Brain Function: fMRI studies suggest that nature exposure increases activity in the brain regions linked to empathy and calm, while reducing activity in the amygdala, which processes fear and stress (Bratman et all, 2015).
Even short exposures like 20 minutes in the park can produce measurable changes. For people with anxiety, this means outdoor therapy offers not just symbolic relief but physiological regulation.
How Nature-Based Therapy Calms the Nervous System
- Sensory Grounding- Nature provides endless opportunities for grounding. The sound of water, the feel of bark, the sight of open skies all stimulate the senses in calming ways. These sensory experiences gently pull people out of anxious thought spirals and into the present moment.
- Rhythms and Patterns-The nervous system responds positively to gentle rhythms such as wave lapping, wind moving through grass, or birdsong. These natural patterns act like co-regulation for the body, slowing breathing and heart rate without conscious effort. Sitting near water or walking under trees can help anxious people experience regulation simply by tuning in to the environment.
- Movement and Bilateral Stimulation-Walking outdoors offers bilateral stimulation (left-right movement), which is also a feature of trauma therapies like EMDR. Gentle walking while in silence or conversation provides less internal pressure and helps regulate the nervous system by engaging the body in rhythmic, bilateral movement.
- Cues for Safety-According to Polyvagal Theory, safety cues calm the vagus nerve and support social engagement. Environments with natural light, open spaces, and non-threatening sensory input provide these cues. Unlike enclosed offices, where fluorescent lights and noise can feel overstimulating, natural settings offer implicit signals of safety and refuge.
Evidence-Based Benefits for Anxiety and Stress
*Forest Bathing (Shinrin-yoku): Japanese studies show that forest walks significantly reduce cortisol and improve mood compared to urban walks (Park et al, 2010).
*Green Exercise: Research shows that exercise in natural environments leads to greater reductions in depression and anxiety than indoor exercise (Barton & Pretty, 2010).
*Attention Restoration Theory: Natural settings replenish directed attention, which is often depleted by the demands of modern life and contributes to mental fatigue and stress (Kaplan & Kaplan, 1989).
Taken together, these findings suggest that outdoor therapy sessions may improve outcomes for people with stress and anxiety disorders, complementing traditional talk therapy approaches.
Mindful Walking: Begin with a slow, intentional walk where the focus is on breathing and noticing surroundings.
Sensory Practices: To begin, engage in one sense at a time. For example, listen for the farthest sound (hearing), or notice three different shades of green (eyesight). This interrupts anxious thought loops and engages the parasympathetic nervous system.
Breathwork Outdoors: Practicing slow, diaphragmatic breathing outdoors can be especially effective, as natural surroundings reinforce calm. People often report it feels easier to slow down in fresh air than inside a building.
Symbolic Exploration: Reflect on metaphors from nature. For example, how a rooted tree weathers storms. Symbolism offers gentle ways to reframe anxious thoughts.
Conclusion
Anxiety and stress place heavy demands on the nervous system. Nature-based therapy provides a direct pathway to regulation, grounding and relief by working with the body’s physiology rather than against it. The gentle rhythms of the natural world can help us move from states of overwhelm into calm and connection.
References:
Barton, J., & Pretty, J. (2010). What is the best does of nature and green exercise for improving mental health? A multi-study analysis. Environmental Science & Technology, 44 (10), 3947-3955.
Bratman, G.N., Hamilton, J.P., Hahn, K.S., Daily, G.C., & Gross, J. J. (2015). Nature experience reduces rumination and subgenual prefontal cortex activation. Proceedings of the National Academy of Sciences, 112 (28), 8567-8572.
Hunter, M.R., Gillespie, B.W., & Chen, S.Y. (2019). Urban nature experiences reduce stress in the context of daily life based on salivary biomarkers. Frontiers in Psychology, 10, 722.
Kaplan, R., & Kaplan, S. (1989). The Experience of Nature: A Psychological Perspective. Cambridge University Press.
Park, B.J., Tsunetsugu, Y., Kasetani, T., Kagawa, T., & Miyazaki, Y. (2010). The physiological effects of Shinrin-yoku (taking in the forest atmosphere or forest bathing): Evidence from field experiments in 24 forests across Japa. Environmental Health and Preventive Medicine, 15(1), 18-26.
Porges, S.W. (20111). The Polyvagal Theory: Neurophysiological Foundations of Emotions, Attachment, Communication, and Self-Regulation. Norton.