70–120 min/week
cumulative weekly green space time linked to emotional outcomes and HRV patterns
Exact: 70-120 minutes
Cumulative weekly green space exposure of ~70–120 minutes is associated with emotional outcomes and HRV amplitude differences in college students
The study used Apple Watch wearables to track multiple dimensions of campus green space exposure over six weeks. Cumulative weekly exposure — the total minutes spent in green spaces across all sessions in a week — of roughly 70 to 120 minutes was linked to emotional wellbeing outcomes and distinct HRV amplitude patterns, a physiological marker of autonomic stress regulation. This suggests that total dose of nature contact per week may matter most for emotional and cardiovascular stress-recovery pathways.
Weekly exposure frequency of approximately 3 sessions per week showed the strongest associations with daytime functioning, while cumulative weekly exposure of approximately 70-120 minutes was associated with emotional outcomes and differences in HRV amplitude patterns.
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