Study: Nature supporting Relaxation
In 2015 a study was complete by Kobayashi et al, to show the autonomic nervous system activity response in different environments.
The nervous system has two arms; the sympathetic nervous system which activity indicates an increase in stresses - get up and go as well as stress and anxieties and the parasympathetic nervous system which activity indicates relaxation - rest and digest.
In this study, 625 participants were exposed to Nature for 15 minutes and after this they showed an 80% increase in parasympathetic nervous system activity. (Relaxed state)
The same participants were then exposed to a city environment for 15 minutes and here they showed an increase of 64% in their sympathetic activity. (Stress state)
You can read the full study here https://www.hindawi.com/journals/ecam/2015/671094/
Abstract from Journal
Recently, there has been growing interest in the effects of the natural environment on human health.
Beneficial effects may include stress relief, improved cognition and physical activity, better social cohesion, and promotion of overall health and mental well-being.
The predisposition of humans to responding positively to the natural environment may be a result of past adaptation to natural environments for survival or ongoing well-being during evolution
The psychological effects of exposure to a forest environment on emotions have been demonstrated by various researchers. Bowler et al. performed a meta-analysis of the results of several studies on the effect of natural environments and concluded that the natural environment has a consistent effect of reducing negative emotions (anger, fatigue, or sadness). In addition, exposure to a forest environment may have a positive effect on psychiatric impairments, such as alcoholic depression.
The current study investigated the effects of forest environments on autonomic nervous activity using heart rate variability (HRV) as an indicator.
The relationship between HRV and autonomic functions has been established by previous studies. Use of HRV as a physiological indicator of stress is also well established.