The Effect of Urban Nature Exposure on Heart Rate Variability

Exposure to nature has been linked to improved psychological and physiological well-being. Two main frameworks, Stress Recovery Theory (Ulrich et al., 1991) and Attention Restoration Theory (Kaplan, 1995), guide most research on nature’s regulatory effects. Many studies have examined physiological regulation through virtual nature exposure or active exposure, such as walking in nature, but less is known about the effects of simply sitting in urban parks, the most accessible natural spaces for the majority of the world’s population. This thesis investigates the influence of nature exposure on heart rate variability (HRV), a marker of autonomic nervous system regulation, at rest, and after an exposure to a brief cognitive stressor, as well as the moderating role of nature connectedness. A sample of 38 university students (Mage= 23.08, SD = 2.02) participated in a within-subject study comparing exposure to an outdoor urban park condition and an indoor office setting condition, with HRV being continuously recorded. Nature connectedness was measured by the Nature Relatedness Scale (NRS) and the Illustrated Inclusion of Nature in Self Scale (IINS). Results showed significantly higher HRV as indexed by RMSSD during nature exposure compared to the indoor condition, indicating greater parasympathetic activation at rest. Nature exposure was also linked to greater HR reduction during recovery following a cognitive stressor, but RMSSD did not significantly differ between the conditions during recovery. Individuals with higher nature connectedness, as measured by the NRS but not the IINS, exhibited greater baseline HRV in the outdoor condition, suggesting a moderating effect of nature connectedness on the relationship between environment and autonomic regulation. Overall findings suggest that nature may facilitate physiological self-regulation. Limitations and future research directions are discussed.