A man goes for a walk on a misty evening in a large American city. The sidewalks are empty. All of his neighbours are inside, naturally, watching television.

A block from home, he is stopped by a police car.

“What are you doing out?” a voice demands.

“Walking,” the man replies.

“Walking where? For what?”

“Walking for air. Walking to see.”

“Have you done this often?”

“Every night for years.”

The car’s rear door swings open and he’s whisked away to the Psychiatric Center for Research on Regressive Tendencies.

The story is a precis of Ray Bradbury’s The Pedestrian, published in 1951 and, until recently, it read less like science fiction and more like reality TV. Americans walk less than most people on the planet. They take about half as many steps as Australians. It’s not uncommon for schoolkids to get a lift to the bus stop at the end of the driveway. Adults idle with the air conditioning cranked in interminable drive-throughs, rather than park and do their business face to face, even if that’s often faster.

But a new craze is sweeping the nation. It’s a simple formula: push off with one foot and swing that leg forward. When your heel strikes the ground, roll your foot until the toes make contact with the floor. Do the same with the other leg. Repeat. If you’re able-bodied, the movement is automatic. You don’t even have to think.

“Let’s go retro, folks,” acting US Surgeon General Boris Lushniak urged at a health forum last year. “We used to walk as a society. Does it take a $150 pair of running shoes, or a $60- to $90-a-month membership in a health club? It doesn’t. It’s walking! Think of it as a patriotic duty for the good of our nation.”

Everyone’s doing it. Last year the Alliance for Biking & Walking confirmed a continuing increase in pedestrianism over the previous decade, while the Centers for Disease Control and Prevention note that, in 2010, 145 million American adults walked for transportation, fun or exercise – up 6% from 2005. It seems that American citizens of all ages have begun asking: could 4,000lb metal boxes powered by petroleum not, in fact, be the most prudent way to travel in cities?

Like opposable thumbs, creative reasoning and protracted adolescence, walking defines us as a species. We used to rely on two feet and a heartbeat for all terrestrial travel. But horses came along, and then the internal combustion engine. Fuelled by affluence and smitten with the mythology of independence, Americans fell hopelessly in love with the car. Cities mushroomed after the second world war, as developers built subdivisions, planners supplied freeways and shopping malls catered to commuters. The auto and oil industries lobbied municipal governments to tear up streetcar tracks, which, on the heels of earlier efforts to criminalise jaywalking, carved out more space for private vehicles. Three-quarters of new houses in the US between 1980 and 2010 were built in the suburbs, even though the reasons people had fled downtown in the first place – open sewers, coal smoke, the plague – were no longer quite so pressing.

But after a decades-long dalliance with cars, could the pendulum be swinging back? In 2011, for the first time in nearly a century, population growth was higher in city centres than in suburbs for the majority of America’s large metropolitan areas. Ageing baby boomers are now bringing their prodigious spending power to dense, safe central districts. Millennials, too, want to live downtown – and, in a development that until recently you might have called un-American, they’re driving less than their parents.

Some of this shift – and the notion of “peak car” – could be a temporary hangover from the subprime mortgage implosion, but it also reflects a desire to socialise online instead of cruising the strip. Say what you want about teenagers these days, but for many of them, owning a car is no longer a rite of passage.

Cities are making it easier, too. Faced with epidemic obesity, productivity-draining gridlock and YouTube-worthy road rage, many are upping their investments in walking and cycling infrastructure. There has been a surge in Complete Streets policies and a host of new physical-activity guidelines. And walking is now socially desirable: many people say they are walking more because it’s seen as a healthy activity.

But it’s not all smooth bipedal sailing. Even though more Americans are walking, the average amount of time they spent on foot actually dipped between 2005 and 2010. Prabasaj Paul of the US National Center for Chronic Disease Prevention and Health Promotion, who produced a report on the subject, speculated that this is because there are more new walkers – “people who are taking baby steps, as it were,” he says. “There’s also a social desirability bias at play. Walking is getting more and more press as a healthy activity, and people may just be saying they walk more because it’s perceived as a good thing.”

Researchers are trying to map out precisely how much a full-fledged walking revolution might help America. Seniors who walk regularly, for instance, are less likely to fall and suffer a debilitating injury. They also have a better shot at avoiding Alzheimer’s. Easy access to trails in urban green space can cut the use of prescription drugs among people suffering from depression. Police officers patrolling on foot can help stop crime and break down some of the barriers between cops and citizens. Property values rise in walkable neighbourhoods. And, if just one in 10 Americans began a regular walking program, predicts the Society of Actuaries – an organisation not known for going out on a limb – the country would save $5.6bn each year in medical costs and lost productivity. Besides, burning a little bit less fuel probably won’t hurt the planet.

Some cities have a long way to go. New Yorkers may be sold on the new trend, but in Orlando, for example, only 1.1% of the population commutes on foot. It is also the city where pedestrians face the highest risk in the country of getting run down while crossing the street. Americans may have slowly started getting to their feet, but it’s not a dramatic comeback it’s just the start of a long stroll.

And, remember, be careful. Matt Green, a former transportation engineer on a quest to walk every block of every street in New York City, was stopped by police while wandering around a housing project in the Bronx. Like Bradbury’s Pedestrian, he tried to justify his ambulatory adventure to the officer. The officer replied: “You tell all that to me, I understand. But these people, they’ll kick your ass.”

• Dan Rubinstein is the author of Born to Walk: The Transformative Power of a Pedestrian Act.
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