“A twenty-minute nature experience was enough to significantly reduce cortisol levels. But if you spent a little more time immersed in a nature experience, 20 to 30 minutes sitting or walking, cortisol levels dropped at their greatest rate. “

Source: https://www.sciencedaily.com/releases/2019/04/190404074915.htm?fbclid=IwAR3AYvXEVUVX7XRSeelwsr2j_WL1dshDFDE5MJlWdkWjL9pK8iWMZmGVZN0