Mental health – good article – minimum 20 minutes 3x a week

From Men's Health. No doubt also applies to women. But there's more to it then in the heading … I excerpted the "5" below

The '20-5-3' Rule Prescribes How Much Time to Spend Outside. Americans today spend 92 percent of their time indoors, and their physical and mental health are suffering. Use this three-number formula to make yourself stronger and happier.

5 Hours

The minimum length of time each month you should spend in semi-wild nature, like a forested state park. “Spending more time in wilder spaces does seem to give you more benefits,” said Hopman.

A 2005 survey conducted in Finland found that city dwellers felt better with at least five hours of nature a month, with benefits increasing at higher exposures. They were also more likely to be happier and less stressed in their everyday lives.

The Finnish government then funded another study in 2014 in which the scientists dumped people in a city center, a city park, and a forested state park. The two parks felt more Zen than the city center. No shocker. Except that those walking in a state park had an edge over the city-park people. They felt even more relaxed and restored. The takeaway: The wilder the nature, the better.

Nature has these effects on the mind and body because it stimulates and soothes us in unusual and unique ways. For instance, in nature you are engulfed in fractals, suggested Hopman. Fractals are complex patterns that repeat over and over in different sizes and scales and make up the design of the universe. Think: trees (big branch to smaller branch to smaller branch and so on), river systems (big river to smaller river to stream and so on), mountain ranges, clouds, seashells. “Cities don’t have fractals,” said Hopman. “Imagine a typical building. It’s usually flat, with right angles. It’s painted some dull color.” Fractals are organized chaos, which our brains apparently dig. In fact, scientists at the University of Oregon discovered that Jackson Pollock’s booze-and-jazz-fueled paintings are made up of fractals. This may explain why they speak to humans at such a core level.