Walking for Mental Health: Why It Works Better Than You'd Think
The surprising neuroscience of why a simple walk can rival medication for mild depression.
The Movement-Mind Connection
The inflammation-stress connection operates through the nuclear factor kappa B (NF-kB) pathway. Psychological stress activates NF-kB, which triggers the production of pro-inflammatory cytokines. These cytokines cross the blood-brain barrier and activate microglial cells (the brain's immune cells), producing neuroinflammation that manifests as fatigue, cognitive fog, anhedonia, and increased pain sensitivity. A 2017 meta-analysis in Molecular Psychiatry found that stress-management interventions — including yoga, meditation, and tai chi — reduced NF-kB activity and downstream inflammatory markers.
Exercise reduces anxiety through mechanisms that go far beyond the popular endorphin explanation. Research published in Cell Metabolism (2014) identified a key molecule — kynurenine — that accumulates during stress and crosses the blood-brain barrier, where it produces neuroinflammation and depression-like symptoms. Skeletal muscle, when activated through exercise, produces an enzyme that converts kynurenine into a form that cannot enter the brain. This finding provides a direct molecular explanation for exercise's antidepressant effects.
It's worth pausing here to address a common misconception. Many people interpret the science of nervous system regulation as suggesting that we should aim for a permanently calm, parasympathetic-dominant state. This is neither possible nor desirable. The sympathetic nervous system exists for excellent reasons: it mobilizes energy for physical activity, sharpens attention during demanding tasks, and enables rapid response to genuine threats. The goal of regulation is not to suppress sympathetic activation but to ensure that the system returns to baseline after activation — and that the activation itself is proportionate to the actual demands of the situation.
Parenting is neurobiologically exhausting because it requires continuous co-regulation — the parent's nervous system must remain regulated enough to serve as an anchor for the child's developing regulatory system. Research from the University of Leiden (2018) demonstrated that parents' cortisol levels directly predicted their children's cortisol patterns, with dysregulated parents producing higher cortisol responses in their children during stress tasks. This finding highlights the invisible labor of parenting: maintaining one's own nervous system state is not selfish but necessary for children's neurological development.
Interoception — the ability to sense internal bodily signals — is increasingly recognized as foundational to emotional regulation. Research published in Biological Psychology (2019) found that individuals with poor interoceptive accuracy were more likely to experience anxiety disorders and had greater difficulty identifying and labeling their emotions. This suggests that learning to sense your own heartbeat, breathing patterns, and gut signals may be as important as any cognitive therapy technique.
How Physical Activity Changes Your Brain
Exercise reduces anxiety through mechanisms that go far beyond the popular endorphin explanation. Research published in Cell Metabolism (2014) identified a key molecule — kynurenine — that accumulates during stress and crosses the blood-brain barrier, where it produces neuroinflammation and depression-like symptoms. Skeletal muscle, when activated through exercise, produces an enzyme that converts kynurenine into a form that cannot enter the brain. This finding provides a direct molecular explanation for exercise's antidepressant effects.
Walking — particularly in natural environments — activates the parasympathetic nervous system through a mechanism researchers call 'soft fascination.' Urban environments demand directed attention (watching for traffic, navigating crowds), which depletes cognitive resources. Natural environments provide indirect attention stimuli (rustling leaves, flowing water, birdsong) that engage the brain without taxing executive function. A Stanford study published in Proceedings of the National Academy of Sciences (2015) found that a 90-minute nature walk reduced activity in the subgenual prefrontal cortex, a region associated with rumination.
The relationship between inflammation and mood is one of the most significant discoveries in psychiatry in the past two decades. Research has demonstrated that approximately one-third of patients with treatment-resistant depression show elevated inflammatory markers, and that anti-inflammatory interventions (including omega-3 supplementation, exercise, and anti-inflammatory diets) can produce antidepressant effects in this subgroup. This 'inflammatory' subtype of depression is characterized by fatigue, psychomotor slowing, and increased sleep — symptoms that differ from the classic 'low serotonin' presentation of decreased appetite, insomnia, and agitation. Recognizing this distinction has important implications for treatment selection.
Stress eating is not a failure of willpower but a neurobiologically driven behavior. During acute stress, cortisol increases appetite specifically for calorie-dense, high-fat, high-sugar foods — a response that evolved to replenish energy stores after physical exertion (fighting, fleeing). Research from the University of California, San Francisco, has shown that these comfort foods temporarily reduce HPA axis activity, creating a genuine (if short-lived) stress-buffering effect. This is why stress eating persists: it works, neurochemically, in the moment.
Fermented foods influence mental health through the gut-brain axis by providing live probiotic organisms and producing neuroactive compounds during fermentation. Kimchi, sauerkraut, yogurt, kefir, and kombucha all contain strains of Lactobacillus and Bifidobacterium that have demonstrated anxiolytic properties in clinical trials. A 2022 study published in Molecular Psychiatry found that a diet enriched with fermented foods for four weeks significantly increased microbial diversity and reduced perceived stress levels, with effects that persisted four weeks after the dietary intervention ended.
The breath is the only autonomic function you can consciously control — making it the most accessible regulation tool you have.
The Nervous System Mechanism
Nature therapy (shinrin-yoku, or forest bathing) has been studied extensively in Japan since the 1980s. Research published in Environmental Health and Preventive Medicine (2010) found that spending two hours in a forest environment reduced cortisol levels by 16%, blood pressure by 2%, and sympathetic nerve activity by 4% compared to equivalent time in an urban environment. The mechanisms include phytoncides (antimicrobial compounds released by trees that modulate immune function), reduced sensory overstimulation, and the restorative effects of fractal patterns in natural landscapes.
Yoga's effects on the nervous system are mediated primarily through two mechanisms: controlled breathing (pranayama) and sustained postures that activate the proprioceptive system. A 2017 study published in the Journal of Alternative and Complementary Medicine found that 12 weeks of regular yoga practice increased GABA levels in the thalamus by 27% — GABA being the brain's primary inhibitory neurotransmitter and the same target as benzodiazepine medications. This suggests that yoga produces genuine pharmacological effects through behavioral means.
This finding aligns with a broader pattern in psychophysiology research: the body's regulatory systems are not fixed but remarkably plastic. When provided with consistent, appropriate inputs — whether through breathwork, movement, social connection, or nutritional support — the nervous system can recalibrate toward more adaptive baseline states. The key word here is 'consistent.' Single interventions produce temporary shifts; sustained practice produces lasting change. Research from the University of Wisconsin's Center for Healthy Minds has demonstrated that as little as two weeks of daily practice can produce detectable changes in neural connectivity, with more substantial structural changes emerging after eight to twelve weeks.
The social dimension of regulation cannot be overstated. Humans are fundamentally social regulators — our nervous systems evolved in the context of close-knit social groups where safety was a collective, not individual, achievement. Research from the University of Virginia has demonstrated that holding a loved one's hand during a mildly stressful task reduces both subjective anxiety and neural threat responses (as measured by fMRI) compared to holding a stranger's hand or no hand at all. This effect is dose-dependent, with relationship quality predicting the magnitude of the calming effect. In an era of increasing social isolation, this research underscores the biological necessity of meaningful human connection.
A 2017 meta-analysis published in Sleep Medicine Reviews analyzed 49 studies and found that cognitive behavioral therapy for insomnia (CBT-I) produced outcomes equal to or better than sleep medication for chronic insomnia — and the effects were more durable. Unlike medication, which loses efficacy over time and carries dependency risks, CBT-I addresses the underlying behavioral and cognitive patterns that perpetuate insomnia.
What 50 Years of Research Shows
Cold exposure triggers the diving reflex — an evolutionarily conserved response that rapidly activates the parasympathetic nervous system. When cold water contacts the face, the trigeminal nerve sends signals to the vagus nerve, producing immediate heart rate reduction and a shift toward parasympathetic dominance. Research from Radboud University Medical Center (2014), led by Wim Hof collaborator Matthijs Kox, demonstrated that cold exposure training combined with breathwork enabled participants to voluntarily influence their immune response — a finding previously thought impossible.
Exercise reduces anxiety through mechanisms that go far beyond the popular endorphin explanation. Research published in Cell Metabolism (2014) identified a key molecule — kynurenine — that accumulates during stress and crosses the blood-brain barrier, where it produces neuroinflammation and depression-like symptoms. Skeletal muscle, when activated through exercise, produces an enzyme that converts kynurenine into a form that cannot enter the brain. This finding provides a direct molecular explanation for exercise's antidepressant effects.
What makes this area of research particularly compelling is the convergence of evidence from multiple disciplines. Neuroscientists, immunologists, endocrinologists, and psychologists are all arriving at the same conclusion from different angles: chronic stress is not merely a psychological experience but a whole-body physiological state with measurable consequences across every organ system. This interdisciplinary consensus represents a significant departure from the historical tendency to treat mental and physical health as separate domains. The implications for clinical practice are profound — effective treatment must address both the psychological and physiological dimensions of dysregulation.
Interoception — the ability to sense internal bodily signals — is increasingly recognized as foundational to emotional regulation. Research published in Biological Psychology (2019) found that individuals with poor interoceptive accuracy were more likely to experience anxiety disorders and had greater difficulty identifying and labeling their emotions. This suggests that learning to sense your own heartbeat, breathing patterns, and gut signals may be as important as any cognitive therapy technique.
The Anti-Inflammatory Effect
The inflammation-stress connection operates through the nuclear factor kappa B (NF-kB) pathway. Psychological stress activates NF-kB, which triggers the production of pro-inflammatory cytokines. These cytokines cross the blood-brain barrier and activate microglial cells (the brain's immune cells), producing neuroinflammation that manifests as fatigue, cognitive fog, anhedonia, and increased pain sensitivity. A 2017 meta-analysis in Molecular Psychiatry found that stress-management interventions — including yoga, meditation, and tai chi — reduced NF-kB activity and downstream inflammatory markers.
Fascia — the continuous web of connective tissue that surrounds every muscle, bone, nerve, and organ — is increasingly recognized as a sensory organ in its own right. Research from the Fascia Research Congress has demonstrated that fascia contains more proprioceptive nerve endings than muscle tissue itself. When fascia becomes restricted through chronic tension, injury, or sedentary behavior, it sends persistent nociceptive (pain) signals to the central nervous system, maintaining a low-level stress response even in the absence of psychological stressors.
The social dimension of regulation cannot be overstated. Humans are fundamentally social regulators — our nervous systems evolved in the context of close-knit social groups where safety was a collective, not individual, achievement. Research from the University of Virginia has demonstrated that holding a loved one's hand during a mildly stressful task reduces both subjective anxiety and neural threat responses (as measured by fMRI) compared to holding a stranger's hand or no hand at all. This effect is dose-dependent, with relationship quality predicting the magnitude of the calming effect. In an era of increasing social isolation, this research underscores the biological necessity of meaningful human connection.
Adaptogens — a class of herbs including ashwagandha, rhodiola rosea, and holy basil — are defined by their ability to normalize physiological function during stress. A 2012 systematic review in Pharmaceuticals found that ashwagandha (Withania somnifera) reduced serum cortisol by an average of 30% in stressed adults. However, the evidence quality remains mixed: many studies have small sample sizes, short durations, and potential conflicts of interest from supplement manufacturers. The most robust evidence supports ashwagandha and rhodiola, while many other marketed adaptogens lack rigorous clinical data.
Toxic positivity — the insistence that one should maintain a positive attitude regardless of circumstances — actively interferes with emotional processing. Research from the University of Texas (2017) demonstrated that suppressing negative emotions increased physiological stress markers (heart rate, skin conductance, cortisol) compared to acknowledging and expressing those emotions. The study found that emotional suppression required significant cognitive effort, depleting executive function resources and paradoxically intensifying the suppressed emotion.
You don't need an hour at the gym. Research shows that three 10-minute walks throughout the day produce equal or greater mood benefits compared to one 30-minute session. The frequency matters more than the duration.
Hormonal and Neurochemical Changes
Nature therapy (shinrin-yoku, or forest bathing) has been studied extensively in Japan since the 1980s. Research published in Environmental Health and Preventive Medicine (2010) found that spending two hours in a forest environment reduced cortisol levels by 16%, blood pressure by 2%, and sympathetic nerve activity by 4% compared to equivalent time in an urban environment. The mechanisms include phytoncides (antimicrobial compounds released by trees that modulate immune function), reduced sensory overstimulation, and the restorative effects of fractal patterns in natural landscapes.
The inflammation-stress connection operates through the nuclear factor kappa B (NF-kB) pathway. Psychological stress activates NF-kB, which triggers the production of pro-inflammatory cytokines. These cytokines cross the blood-brain barrier and activate microglial cells (the brain's immune cells), producing neuroinflammation that manifests as fatigue, cognitive fog, anhedonia, and increased pain sensitivity. A 2017 meta-analysis in Molecular Psychiatry found that stress-management interventions — including yoga, meditation, and tai chi — reduced NF-kB activity and downstream inflammatory markers.
The concept of 'dose-response' in regulation practices is important and often overlooked. Just as medication has an optimal dose range — below which it's ineffective and above which side effects emerge — regulation practices have optimal duration and intensity parameters. Research from Emory University (2019) found that meditation sessions of 10-20 minutes produced the greatest anxiolytic effects, with diminishing returns beyond 30 minutes and some participants actually reporting increased anxiety during sessions longer than 45 minutes (likely due to sustained interoceptive focus amplifying anxious body sensations in untrained practitioners). Starting with shorter sessions and gradually increasing is both safer and more sustainable.
The autonomic nervous system operates largely below conscious awareness, governing heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal. It consists of two primary branches: the sympathetic nervous system, which mobilizes the body for action, and the parasympathetic nervous system, which promotes rest, recovery, and digestion. Understanding this fundamental division is the first step toward meaningful nervous system regulation.
Sleep remains the single most potent nervous system regulation intervention available, yet it is consistently the most neglected. During sleep — particularly during slow-wave and REM stages — the brain undergoes critical maintenance processes: clearing metabolic waste through the glymphatic system, consolidating memories, processing emotional experiences, recalibrating stress hormones, and repairing cellular damage. The research is unequivocal: there is no aspect of physical or mental health that is not impaired by insufficient sleep, and no amount of other regulation practices can compensate for chronic sleep deprivation. Prioritizing sleep is not optional — it is the foundation upon which all other regulation efforts rest.
Optimal Dose and Timing
Dance therapy engages the nervous system differently from structured exercise because it involves spontaneous, self-directed movement without performance pressure. Research from the University of Hertfordshire (2019) found that free-form dance for 30 minutes produced greater reductions in cortisol and greater increases in serotonin than equivalent-intensity structured exercise. The researchers attributed this to the combination of rhythmic movement, musical engagement, and the absence of performance evaluation — essentially creating a safe space for the body to move without the sympathetic activation that often accompanies exercise in competitive or evaluative contexts.
Yoga's effects on the nervous system are mediated primarily through two mechanisms: controlled breathing (pranayama) and sustained postures that activate the proprioceptive system. A 2017 study published in the Journal of Alternative and Complementary Medicine found that 12 weeks of regular yoga practice increased GABA levels in the thalamus by 27% — GABA being the brain's primary inhibitory neurotransmitter and the same target as benzodiazepine medications. This suggests that yoga produces genuine pharmacological effects through behavioral means.
A nuanced understanding of the stress response includes recognizing that not all stress is created equal. Acute, time-limited stress followed by recovery (eustress) actually strengthens the nervous system's regulatory capacity through a process called hormesis — similar to how exercise stresses muscles to make them stronger. The problem arises with chronic, unrelenting stress that prevents recovery, or with traumatic stress that overwhelms the system's capacity to process. This distinction matters for practical decision-making: avoiding all stress is neither possible nor beneficial. The goal is to ensure adequate recovery between periods of activation and to avoid sustained activation without relief.
A 2017 meta-analysis published in Sleep Medicine Reviews analyzed 49 studies and found that cognitive behavioral therapy for insomnia (CBT-I) produced outcomes equal to or better than sleep medication for chronic insomnia — and the effects were more durable. Unlike medication, which loses efficacy over time and carries dependency risks, CBT-I addresses the underlying behavioral and cognitive patterns that perpetuate insomnia.
Perfectionism operates as a chronic stress generator because it creates an impossible standard against which all performance is evaluated. Research by Thomas Curran and Andrew Hill, published in Psychological Bulletin (2019), found that perfectionism has increased substantially across generations, with socially prescribed perfectionism (the belief that others demand perfection from you) showing the steepest rise. This form of perfectionism is most strongly associated with anxiety, depression, and burnout because the source of the standard feels external and uncontrollable.
Comparing Different Approaches
Yoga's effects on the nervous system are mediated primarily through two mechanisms: controlled breathing (pranayama) and sustained postures that activate the proprioceptive system. A 2017 study published in the Journal of Alternative and Complementary Medicine found that 12 weeks of regular yoga practice increased GABA levels in the thalamus by 27% — GABA being the brain's primary inhibitory neurotransmitter and the same target as benzodiazepine medications. This suggests that yoga produces genuine pharmacological effects through behavioral means.
Therapeutic tremoring — the body's natural mechanism for discharging accumulated stress energy — was first systematically studied by David Berceli, who developed Tension and Trauma Releasing Exercises (TRE). The tremoring mechanism originates in the psoas muscle, the deepest hip flexor, which contracts during the fight-or-flight response. When this muscle is deliberately fatigued and then allowed to relax, it spontaneously produces tremors that propagate through the body, releasing stored muscular tension. Research published in the Journal of Traumatic Stress (2016) found that TRE practice significantly reduced PTSD symptoms in military veterans.
What makes this area of research particularly compelling is the convergence of evidence from multiple disciplines. Neuroscientists, immunologists, endocrinologists, and psychologists are all arriving at the same conclusion from different angles: chronic stress is not merely a psychological experience but a whole-body physiological state with measurable consequences across every organ system. This interdisciplinary consensus represents a significant departure from the historical tendency to treat mental and physical health as separate domains. The implications for clinical practice are profound — effective treatment must address both the psychological and physiological dimensions of dysregulation.
The hormonal stress response in women involves additional complexity beyond the HPA axis. Estrogen and progesterone modulate cortisol sensitivity, serotonin production, and GABA receptor function, which is why stress symptoms often fluctuate across the menstrual cycle. Research published in Biological Psychiatry (2018) found that women in the luteal phase (post-ovulation) showed heightened amygdala reactivity to threatening stimuli and reduced prefrontal regulation — essentially creating a window of increased vulnerability to anxiety and stress.
Who Benefits Most
Yoga's effects on the nervous system are mediated primarily through two mechanisms: controlled breathing (pranayama) and sustained postures that activate the proprioceptive system. A 2017 study published in the Journal of Alternative and Complementary Medicine found that 12 weeks of regular yoga practice increased GABA levels in the thalamus by 27% — GABA being the brain's primary inhibitory neurotransmitter and the same target as benzodiazepine medications. This suggests that yoga produces genuine pharmacological effects through behavioral means.
Fascia — the continuous web of connective tissue that surrounds every muscle, bone, nerve, and organ — is increasingly recognized as a sensory organ in its own right. Research from the Fascia Research Congress has demonstrated that fascia contains more proprioceptive nerve endings than muscle tissue itself. When fascia becomes restricted through chronic tension, injury, or sedentary behavior, it sends persistent nociceptive (pain) signals to the central nervous system, maintaining a low-level stress response even in the absence of psychological stressors.
Recent advances in wearable technology have made it possible for individuals to track their own nervous system state in real time. Devices measuring HRV, electrodermal activity (skin conductance), and continuous heart rate provide biofeedback that was previously available only in clinical settings. Research from the University of Zurich (2020) found that HRV biofeedback training — where individuals learn to increase their HRV in real time using visual or auditory feedback — produced significant improvements in anxiety, depression, and stress resilience that were maintained at six-month follow-up. While these tools are not replacements for professional care, they democratize access to physiological self-awareness.
The anti-inflammatory diet for stress management focuses on foods that reduce systemic inflammation: fatty fish (omega-3s), leafy greens (folate, magnesium), berries (anthocyanins), turmeric (curcumin), nuts (vitamin E, selenium), and fermented foods (probiotics). A 2019 randomized controlled trial published in PLOS ONE found that participants following a Mediterranean-style anti-inflammatory diet for 12 weeks showed significant reductions in depression, anxiety, and stress scores compared to a control group receiving social support alone.
Getting Started Safely
Fascia — the continuous web of connective tissue that surrounds every muscle, bone, nerve, and organ — is increasingly recognized as a sensory organ in its own right. Research from the Fascia Research Congress has demonstrated that fascia contains more proprioceptive nerve endings than muscle tissue itself. When fascia becomes restricted through chronic tension, injury, or sedentary behavior, it sends persistent nociceptive (pain) signals to the central nervous system, maintaining a low-level stress response even in the absence of psychological stressors.
Swimming combines multiple nervous system regulation mechanisms: the diving reflex triggered by water contact, hydrostatic pressure that provides gentle proprioceptive input across the entire body, rhythmic bilateral movement that activates cross-hemisphere brain coordination, and the meditative quality of regulated breathing. A 2019 systematic review in the British Journal of Sports Medicine found that swimming was associated with a 28% lower risk of all-cause mortality compared to sedentary individuals — a larger reduction than walking or cycling.
It's worth pausing here to address a common misconception. Many people interpret the science of nervous system regulation as suggesting that we should aim for a permanently calm, parasympathetic-dominant state. This is neither possible nor desirable. The sympathetic nervous system exists for excellent reasons: it mobilizes energy for physical activity, sharpens attention during demanding tasks, and enables rapid response to genuine threats. The goal of regulation is not to suppress sympathetic activation but to ensure that the system returns to baseline after activation — and that the activation itself is proportionate to the actual demands of the situation.
The breath is the only autonomic function that can also be consciously controlled, making it a unique bridge between voluntary and involuntary nervous system activity. Research published in the Journal of Neurophysiology (2017) identified a cluster of neurons in the brainstem — the pre-Botzinger complex — that directly links breathing rhythm to arousal states. This neural circuit explains why slow, deep breathing genuinely calms the nervous system rather than merely providing a distraction.
Decision fatigue is not merely a colloquial complaint but a well-documented cognitive phenomenon. A famous study of Israeli parole judges published in the Proceedings of the National Academy of Sciences (2011) found that the probability of a favorable ruling dropped from about 65% at the start of a session to nearly 0% just before a break — then reset to 65% after the break. This research demonstrates that decision-making depletes a finite cognitive resource, and that the depleted brain defaults to the path of least resistance.
Building a Sustainable Practice
Yoga's effects on the nervous system are mediated primarily through two mechanisms: controlled breathing (pranayama) and sustained postures that activate the proprioceptive system. A 2017 study published in the Journal of Alternative and Complementary Medicine found that 12 weeks of regular yoga practice increased GABA levels in the thalamus by 27% — GABA being the brain's primary inhibitory neurotransmitter and the same target as benzodiazepine medications. This suggests that yoga produces genuine pharmacological effects through behavioral means.
Walking — particularly in natural environments — activates the parasympathetic nervous system through a mechanism researchers call 'soft fascination.' Urban environments demand directed attention (watching for traffic, navigating crowds), which depletes cognitive resources. Natural environments provide indirect attention stimuli (rustling leaves, flowing water, birdsong) that engage the brain without taxing executive function. A Stanford study published in Proceedings of the National Academy of Sciences (2015) found that a 90-minute nature walk reduced activity in the subgenual prefrontal cortex, a region associated with rumination.
Recent advances in wearable technology have made it possible for individuals to track their own nervous system state in real time. Devices measuring HRV, electrodermal activity (skin conductance), and continuous heart rate provide biofeedback that was previously available only in clinical settings. Research from the University of Zurich (2020) found that HRV biofeedback training — where individuals learn to increase their HRV in real time using visual or auditory feedback — produced significant improvements in anxiety, depression, and stress resilience that were maintained at six-month follow-up. While these tools are not replacements for professional care, they democratize access to physiological self-awareness.
The autonomic nervous system operates largely below conscious awareness, governing heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal. It consists of two primary branches: the sympathetic nervous system, which mobilizes the body for action, and the parasympathetic nervous system, which promotes rest, recovery, and digestion. Understanding this fundamental division is the first step toward meaningful nervous system regulation.
Sources & Further Reading
- Berceli, D., et al. (2016). Effects of self-induced unclassified therapeutic tremors on quality of life among military veterans. Journal of Traumatic Stress, 29(4), 1-6.
- Bratman, G.N., et al. (2015). Nature experience reduces rumination and subgenual prefrontal cortex activation. Proceedings of the National Academy of Sciences, 112(28), 8567-8572.
- Streeter, C.C., et al. (2007). Yoga asana sessions increase brain GABA levels: A pilot study. Journal of Alternative and Complementary Medicine, 13(4), 419-426.
- Kox, M., et al. (2014). Voluntary activation of the sympathetic nervous system and attenuation of the innate immune response in humans. Proceedings of the National Academy of Sciences, 111(20), 7379-7384.
- Li, Q. (2010). Effect of forest bathing trips on human immune function. Environmental Health and Preventive Medicine, 15(1), 9-17.
