Here’s a New Year’s resolution you’ll want to follow through on: take more nature showers, ideally with a friend. Or friends.

As is usually the case with good ideas, there’s nothing new about this except the way we talk about it. “Taking a nature shower” is just another way of saying you should walk in the woods. It diminishes this most simple and pure activity by draping it in New Age hokum. On the other hand, it does highlight the salubrious benefits. It suggests that you’ll feel cleaner and fresher afterwards, which is the truth.

You don’t have to go far to find endorsements for what is also called ecotherapy, or green therapy.  There’s this article on WebMD, which says it’s being used to “treat a variety of medical conditions, from post-cancer fatigue to obesity, hypertension (high blood pressure), and diabetes.” There are also bestsellers and academic studies.

And there’s this good, old-fashioned long-form-journalism story in Outside, which details some of the specific health benefits. The author explains how Japan has embraced the notion, building 48 Forest Therapy trails in parks, where people can practice shinrin-yoku, or forest bathing. (The Japanese government actually coined that term, in 1982, which demonstrates pretty convincingly that we’re dealing with a very different culture here.)

Walking in nature shouldn’t be confused with spending 20 minutes on your treadmill or strolling to the corner grocery. Japanese researchers “have found that leisurely forest walks, compared with urban walks, yield a 12.4 percent decrease in the stress hormone cortisol, a seven percent decrease in sympathetic nerve activity, a 1.4 percent decrease in blood pressure, and a 5.8 percent decrease in heart rate.”

Forest walks can also increase infection-fighting white blood cells: in one study of middle-aged Japanese men, three days in the woods boosted one category of those cells by 40 percent. And the levels stayed elevated a month after returning to the city.

Why is walking in the woods good for you? One theory discussed in the Outside story is that aerosols emitted by trees have a marked physiological impact on humans…which sounds like aromatherapy, which sounds even more New Age-y than “forest bathing.” But I’m not dismissing it, because I know how my breathing changes after about five minutes in a pine grove.

Bottom line: science says you should make a point of hiking in the woods in 2013. Doing it with a friend is my idea.

Photo from National Park Service Digital Archive, Muir Woods National Park.