It's National Park Week from April 18 to 26 and Earth Day on the 22nd, but that's not why Chris Fiscus is taking his kids hiking this weekend. They go regularly because it's good for them, and because Chris likes to see Cole, 13, without a computer in his lap and Brady, 9, hold a water bottle instead of a video game controller.

"My wife and I want to raise our kids to be balanced and to know that they don't have to experience everything through an app," said Fiscus, 47, vice president and director of public relations at Moses Inc., a digital marketing and advertising agency. "Technology is great, but everyone needs time to unplug and get away."

Although the boys often respond to hiking plans with eye rolls and sighs, Fiscus and his wife, Susie, continue to lead their kids on adventures to visit the birds, cacti and mountains surrounding their Phoenix home.

"It's valuable family time," he said.

The Fiscuses' commitment to raising nature-loving kids is increasingly rare among American parents. According to the National Wildlife Federation, the average American child has just four to seven minutes of "unstructured outdoor play" each day and spends more than seven hours staring at television, computer or phone screens.

Additionally, one University of Michigan research study found that, from 2002 to 2003, 6- to 17-year olds in the U.S. spent 50 minutes, on average, on outdoor activities each week, compared to the one hour and 40 minutes reported by kids the same age between 1981 to 1982.

"The disconnect between kids and nature is one of the greatest crises of our time," said Scott Sampson, chief curator at the Denver Museum of Nature and Science and author of the recently released book, "How to Raise a Wild Child: The Art and Science of Falling in Love with Nature." He, along with others who have researched the health benefits of spending time outside, is an evangelist of nature's importance, urging parents to prefer hikes or picnics over video games and movies.

"I'm not saying we need to unplug entirely and go back to nature," Sampson said. "We can use technology to leverage our ability to get kids outdoors."

Resisting the temptation to remain indoors

The Fiscus family may regularly trade their couch for adventures in nature, but Chris said there's still slight resistance from each family member when hikes are planned.

"It's like that feeling you get when you're invited to a party. You'd rather not go, because you want to watch TV and relax at home, but when you get there, you have a great time," he said.

This temptation to stay home likely resonates with many parents, especially those who struggle to make time for outdoor fun in busy schedules, said Dr. Eva Selhub, a physician and resiliency coach. Somehow, taking a family hike or going on a picnic never seems to get crossed-off the parenting to-do list.

In that way, nurturing a love of nature is like many healthy habits, she added. People see the value in it, but get distracted by other, less enriching activities.

"It's the same reason we eat French fries even though eating salad is good for us," she said. "Our culture loves immediate gratification and, if something takes extra effort," we end up avoiding it.

Through her speaking and writing, Selhub tries to add a sense of urgency to people's innate grasp of nature's importance. She highlights the many health benefits linked to spending time in green space, explaining how even a quick walk around the block can reduce stress and boost the immune system.

"When you are in nature, it's like a drop of morphine in the brain. … You feel connected to something larger than yourself," said Selhub, whose new book, "Your Health Destiny: How to Unlock Your Natural Ability to Overcome Illness, Feel Better and Live Longer," cites time outside as a natural cure for many health woes.

The link between time in nature and personal well-being likely results from the thousands of years humanity spent living in rural conditions, she added. The brain and the body's five senses are designed to respond to the great outdoors, not the monotony of office life or the chaos of big cities.

"Big cities haven't been around long enough for our brains to be used to living in a concrete world," Selhub said.

For children, time outside is an invaluable part of growing up, Sampson said. "Unstructured free play, in which kids drive the activity, is essential for growing bodies and minds. That's where they learn to be little scientists and creative thinkers."

A recent article in The Washington Post reported that time in nature will become increasingly important as more and more Americans move to cities. "The World Health Organization predicts that 70 percent of the world's population will live in urban areas within 30 years," the article noted.

In 2014, Slate described a doctor who wrote "nature prescriptions" in response to conditions like high blood pressure, diabetes, obesity and depression.

After an afternoon hike, Fiscus observes a sense of calm settle over his household.

"The mental benefits are just as important as the physical ones," he said.

Easy ways to get active outside

One of Fiscus' most memorable outdoor experiences was spending two weeks visiting Utah's national parks and the north rim of the Grand Canyon on a family vacation a few years ago.

"We still talk about it," he said. "That was really when my kids caught the hiking bug. It was great, as parents, to see their eyes opened to the awesomeness of nature."

It was incredible to essentially be free from computers, televisions and other devices for nearly two weeks, Fiscus said. It gave the family time to just talk, laugh and walk together.

Although he's heard many parents tell similar stories, Sampson said it doesn't take a grand adventure to nurture young nature lovers.

For example, he credits a quiet moment in a pond about a block and a half from his childhood home in Vancouver, British Columbia, with igniting his love of nature. His mom had walked him there when he was 4 or 5 to see the tadpoles.

"I had on these big, black rubber boots and I stepped into the pond. … I kept walking in and, eventually, the water was over my waist," Sampson remembered. "I was totally immersed and surrounded by millions of tadpoles.

"It was the first time in my life I felt completely connected with the world. There was no separation between me and the pond," he added. "Experiences like that led me to become a scientist."

All it takes to raise a "wild child," or a kid who finds joy in and feels comfortable spending time outside, is a spirit of fun, Sampson said. "You have to make it engaging for kids."

That's often where technology can come in, he noted. Parents can use smartphone-based activities to tempt their kids into playing outside.

"You can download apps to your phone that allow kids to identify plants, rocks, animals, stars, clouds — you name it," he said. "Or you can have your kids take pictures of 10 cool things they find to create a photo essay to share with friends."

Other enticing outdoor activities include geocaching, which is like a global scavenger hunt, or taking older children on challenging surfing, skiing or backpacking trips, Sampson added. The "How to Raise a Wild Child" website lists even more ideas.

No matter what activity families settle on, parents should first and foremost remember to model a love of nature for their kids, Sampson said.

"Parents have to pause once in a while to look at the birds and smell the flowers," he said. "Our kids follow what we do."

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