Combined Effect of Walking and Forest Environment on Salivary Cortisol Concentration

Summary & key facts

Seventy-four young men walked for 15 minutes in both a forest and an urban area, with saliva taken before and after each walk. Mean salivary cortisol dropped after the forest walk (from 9.70 to 8.37 nmol/L) but hardly changed after the urban walk (from 10.28 to 10.01 nmol/L). Statistical tests showed a significant combined effect of walking plus environment (interaction p < 0.001), and the study also found that 69% of participants had lower cortisol after forest-walking versus 60% after just viewing forests (this difference was not statistically significant, p = 0.093).

Key facts:

• Sample: 74 young male participants walked for 15 minutes in forest and urban environments, with saliva collected before and after walking.
• Forest walk result: mean salivary cortisol decreased from 9.70 nmol/L before walking to 8.37 nmol/L after walking.
• Urban walk result: mean salivary cortisol changed little, from 10.28 nmol/L before walking to 10.01 nmol/L after walking.
• Statistics: a two-way repeated-measures ANOVA found a significant interaction between environment and walking (p < 0.001). The main effects were also significant (walking p < 0.001; environment p = 0.001).
• Responder comparison: 69% of participants showed lowered cortisol after walking in the forest, compared with 60% who showed lowered cortisol after viewing forest scenes; this difference was not statistically significant (p = 0.093).
• Context note: the study tested young men only, so the findings apply directly to that group and may not generalize to other ages or to women.

Abstract

We investigated the effects of walking in a forest environment on salivary cortisol concentrations. Seventy-four young male participants walked for 15 minute...

Topics

Stress Responses and Cortisol Urban Green Space and Health

Categories

Environmental Science Health, Toxicology and Mutagenesis Physical Sciences

Tags

Environmental science Internal medicine Medicine Saliva