It’s taken a few years, but parkour (pronounced par-KOOR), an underground sport that originated in divergent metropolitan areas throughout Paris, has come to Midwestern suburban gymnasiums. This fall, Gleason’s Gym in Eagan offers a second year of classes in freerunning, a more experimental form of Parkour. As an adventure sport without all the testosterone, freerunning is a phenomenon, like the Susan Boyle moment, that is surely one of the more welcome byproducts of the YouTube era.

Parkour merges easy running with low-level acrobatics -- pommeling, pulling, swinging and somersaulting -- to move over and through the obstacles of urban living. Free-runners combine the joyful creativity of Jackie Chan with the vertical aspirations of Spiderman to propel themselves across our infrastructure -- alongside it walls, atop its structures, into its windows and descending its canyons.

You can think of parkour as gymnastics freed of judges and East German coaches and put to better use helping everyday athletes learn to move like superheroes. Then there’s the philosophical appeal of parkour, its yin to the yang of all the aggression in sport today.

"I think of it as the flight part of the fight-or-flight response," says Chad Zwadlo, an expert freerunner and instructor at Gleasons. "As a very disciplined form of running away."

Physically, freerunning offers a way to rebel against the prevailing mindset so often at work within health clubs. Consider your typical leg press, leg extension, bench press or tricep press exercise. Conventional exercises such as these tell us only one story about strength: that it is manifested through pushing (rather than pulling), using objects (rather than the body), in single-joint movements (rather than multijoint movements), and largely while seated (rather than standing or even running).

This one-dimensional fare, while a convenient way to manage crowds, ignores at least half of all the body is designed to carry out. "It’s the difference between using your body to move an object through space," says Zwadlo, "and using an object to move your body through space."

Parkour develops agility, a skill that is highly trainable and yet virtually nonexistent within our narrowly focused cardio and strength training paradigms. Parkour also embodies the fact that flexibility is meaningless without mobility. Freerunning, finally, involves the ability to reduce force as well as produce it. As studies of jump training has shown, the high disparity toward anterior cruciate ligament (ACL) tears in girls could be nearly wiped out if we spent more time teaching them how to absorb and transfer forces upon landing.

Landing, it turns out, is one of the things freerunners do best. Elite freerunners have been filmed rolling through 10-foot landings so effortlessly that last summer, Popular Science calculated the physics behind how they do so without breaking their bones. (The 12,000 pounds created by such a leap, it determined, are reduced to a more manageable 460 thanks to having extended the period of impact with a roll.)

"Landing is one of the scariest parts of parkour," says Zwadlo. "We try to have as little impact as possible."

The showreel for Zwadlo’s class is a heartwarming testament to the resourcefulness and resolve of parents of ambitious young freerunners.  "A lot of parents bring their kids in because they know their kids are going to try these things and they want them to learn how to do them safely," he says. Zwadlo also adds that the overcoming of physical obstacles in parkour offer a valuable lesson about life obstacles as well.

The Gleason’s course is one of only a handful of such programs being offered across the country. It teaches a progressive succession of basic skills necessary to freerunning, and has drawn students as young as 5 but also as old as 60. Zwadlo also organizes a monthly meet-up of local participants,  a group that often meets on the University of Minnesota campus.

For a taste of what elite freerunning looks like, you could do worse than check out this impressive greatest hits video from an athlete named Levi Meeuwenberg. The lag time between the emergence of an organic movement and its appropriation by corporate sponsorships is apparently now measurable in minutes, not hours; the video is intercut with brand impressions for athletic shoes, electronics, energy drinks and the latest Madonna video. But it will take a lot more selling out than this to lose your sense of awe for so many kids having learned how to fly.

One last note: Try to forgive the relentless scoring of most of these videos with adrenaline-pumping club music. It may convey a misplaced message that parkour is a sport for thrill seekers and other casualties of the cable-TV environment, but given the sport’s potential for self expression, improvisational exercise and locomotion as rebellion, someday someone will set some of these images to an Ennio Morricone soundtrack. The perfect backdrop for the timeless beauty of humans in movement across a rugged terrain.

Freelancer Paul Scott, of Rochester, writes frequently about health and fitness for various media. Susan Perry is on vacation.