Table 5.

Measured effects of time in nature via included studies 31–60 min of walking outdoors: natural vs. urban setting.

Dose	Study	Measured effect (from natural setting when compared to urban setting)
50-min Arboretum walk vs. Urban walk	#1 (Berman et al., 2008)	When compared to those walking in the city, those walking in the natural setting showed: Mood (PANAS—positive subscales) - No significant difference measured between groups Attention - A greater increase of 1.5 digits on backwards digit-span task (t(36) = 4.783, prep = 0.99)
50-min Nature reserve walk vs. Urban city walk	#2 (Hartig et al., 2003)	When compared to those walking in the city, those walking in the natural setting showed: Physiology (blood pressure) - A greater decrease in blood pressure, 30 minutes into walk (p < 0.01). Significance lost at the end of the trial. Emotion (ZIPERS)(OHS) - A greater increase in positive emotion, and a greater decrease in feelings of anger and aggressiveness (p < 0.01) (ZIPERS) - No significant difference measured in overall happiness (OHS) Attention (NCPCT) - No significant change in attention could be measured.
50-min Park walk vs. Urban walk	#3 (Johansson et al., 2011)	When compared to those walking in the city alone and with a friend, those in the natural setting showed: Affect (EFI scale) (NMS scale) - An increase in revitalization while walking alone and while walking with a friend. The greatest effect was observed while walking alone (p < 0.05) (EFI) - A decrease in feelings of being rushed while walking alone (p < 0.05) (NMS) Attention (Symbol Substitution Test) - A decline in attention score results (p < 0.05) < Result was unexpected> Perceived Stress (PSS) - No significant difference was noticed in PSS.