npj Urban Sustainability, April 2026 | Karl Samuelsson et al., University of Gävle
Exercise improves recovery. Time outdoors reduces stress. Researchers at the University of Gävle found that when the two happen together, the body recovers better overnight than when either happens alone.
The team tracked participants over several months using wearables that measured how well their bodies recovered during sleep. On days when participants were physically active in natural settings, their overnight recovery was measurably better than on days when they got the same exercise indoors or in urban environments. Sitting passively in nature helped some. Moving through nature helped more.
Being in nature shifts the body out of stress mode by lowering stress hormones and settling the nervous system. Exercise deepens that effect rather than simply adding to it, and the benefit carries through to sleep. Women in the study saw stronger results than men, which is consistent with other research on how the sexes respond differently to stress, though exactly why remains an open question.
Because the study tracked people through their normal daily lives over months, the findings are more applicable than a single lab experiment. The practical implication is simple: the same walk taken outdoors rather than on a treadmill, or the same run taken on a trail rather than a track, produces better recovery during sleep that night.
