60秒科学:大自然是活力之母(有声)（在线收听）

It’s refreshing. It’s invigorating. And it leaves you feeling truly alive. No, I’m not talking about a cold shower or a fruit smoothie with a mochachino chaser. I’m talking about nature. Because according to a study published in the Journal of Environmental Psychology, getting outside—or even just thinking about it—can increase your vitality.

Hiking, biking or walking in the woods can be revitalizing. But why? Is there something special about the great outdoors that recharges our batteries? Or is it that enjoying nature often involves physical activity and, unless you’re Henry David Thoreau, interacting with others?

To find out, psychologists conducted a series of experiments to isolate nature from the equation. In one study, for example, they had undergraduates take a 15-minute walk along a tree-lined river bank or through an indoor hallway. And they quizzed students on how energized they felt before and after the stroll.

The results: participants who spent time outside, whether alone or with company, reported greater feelings of vitality. It even worked when the students looked at pictures of plants, or imagined being outdoors. So when you’re looking for that late-afternoon energy boost, try a walk in the park. Think of it as a "leaf" of absence