In the topsy-turvy world of trampolines, everything that goes down must come up again. Back in the 1960s, trampoline parks were, much like hula-hoop competitions, a big fad. But they were done in by personal-injury lawsuits and had long been forgotten by most people, including the two men largely responsible for their contemporary rebirth: the father-and-son team of Rick and Jeff Platt.
Eight years ago, Rick Platt was looking for something to do with the fortune he had made trading metals in the commodities market and decided it would be fun to own a professional sport. "People own sports teams. They own sports leagues. But an entire game?" says Jeff. "My father likes to think big."
Before long, the Platts bought the patent for Sky Zone, a combination of football, basketball, hockey and gymnastics played atop a bunch of trampolines cabled together to create a super-trampoline roughly the size of a basketball court. They rented a warehouse in Las Vegas and in 2002 installed a 130-by-70-ft. (40-by-21-m) trampoline. For the next two years, they trained two 12-man teams to play Sky Zone, in which points are scored by throwing a Nerf-like ball through a triangular net or by leaping through a spinning hoop suspended 7 ft. (2 m) above the trampoline.
In 2004 the Orleans Arena in Vegas hosted the first exhibition Sky Zone game. It was a total flop. "Let's just say that ESPN and Nike were not knocking down our doors," says the younger Platt.
But as luck would have it, the Sky Zone warehouse was right next to an indoor skate park, whose patrons needed a safe place to practice their more extreme moves. "They'd knock on our doors all the time, wanting to jump," says Jeff. So he and his dad bought a cash box and salvaged their enterprise by charging skate rats $10 or so to bounce around for an hour.
The Platts have since opened two more Sky Zone jump centers, in St. Louis and Sacramento, with five others being built and a dozen more slated to open in 2011. Sky Zone's success helped spawn a number of competing chains, including Jump Street, Jump Sky High and the newest, House of Air, set to open in San Francisco in September.
These parks are a lot safer than the ones in the 1960s. For starters, trampoline-covered walls make it impossible to bounce off and onto the ground. Thick padding covers the springs, and there are safety nets beneath the seams. Still, about 1% of Sky Zone's million or so visitors in the past six years have logged injuries--mostly finger jams, sprains and the like. "As with any extreme sport," says Jeff, "accidents are going to happen." And some will be serious. The worst so far is a woman who became paralyzed after landing a flip wrong.
Flips, however, are the key to the trampoline park's comeback as a training ground for skate- and snowboarders . House of Air is installing a DJ booth and giant video screen, and co-owner Paul McGeehan says he expects to see a wide range of clientele: from couples on first dates to kiddies acting out their Quidditch fantasies. "All ages," agrees Jump Sky High founder Jerry Raymond. "It's almost like the new bowling alley." Or like hula-hooping coming around again.
This article originally appeared in the August 16, 2010 issue of TIME.