The fastest speed ever achieved on a water slide is 57 miles per hour. It was clocked in 2009 on the Kilimanjaro, a 164-foot-high, 50-degree plummet at Águas Quentes, a water park outside of Rio de Janeiro, by Jens Scherer, a German advertising executive. Scherer, 30, the reigning champion of competitive "speed chuting," also holds four Guinness world records in the sport, including the one-day distance record, for chuting 94 miles on a slide near Munich. That's like traveling all the way from New York to Philadelphia on the bare skin of your back. During those 24 hours, he slept for just an hour and a half and climbed 30,000 vertical feet worth of steps, the equivalent of hiking from sea level to the summit of Mount Everest.

Jens Scherer Scherer out of the chute (Photograph by Nick Roberts)

Joshua Foer The author, a proud runner-up (Photograph by Nick Roberts)

Approaching 60 miles an hour on a water slide is not simply a matter of leaping and letting gravity do its thing. Speed chuting is a skill. An art. And there are people who take it very, very seriously. Almost all of them are German, and there are more of them every year. They compete on teams with names like Slide Fast, Die Young and regularly travel many hours to weekend tournaments sponsored by water parks across their country.

"Speed chuting," like "skiing," is a catchall term that encapsulates a range of events, from simple top-to-bottom timed runs to sliding marathons (fastest to cover 26.2 horizontal miles). For the moment, it remains an exclusively German sport whose place in the national athletic firmament perhaps best resembles paintball in the U.S. Those who compete are crazed; those who don't find it odd and maybe even a little scary.

When I first heard about speed chuting, this past winter, it didn't sound scary to me. It sounded freaking sweet. So in February I called up Scherer to find out how I could get in on the action. My timing couldn't have been better, Scherer told me. In late March, the German National Speed Chuting Championship, the Kentucky Derby of the sport's yearlong circuit, would be held in the Baltic Sea resort town of Scharbeutz. To my surprise, Scherer noted that the contest was open to anyone. Even more tantalizing, no American had ever competed in speed chuting, meaning the title of American champion was unclaimed. I decided I ought to do something about that.

"If you come a few days early, I would be happy to teach you my techniques," Scherer graciously offered. "You can crash on my couch."

LET ME BE FRANK: Nobody would ever mistake me for someone who belongs in a major athletic competition. My daily exercise regimen consists of a half-mile shuffle to the coffee shop to pick up a pair of banana-oat mini-muffins. Fortunately, Scherer hadn't seemed fazed when I noted my lack of fitness. He gave me some basic advice to start prepping for what he described as "rocking the tube."

Training for speed chuting, he explained, is sort of like powerlifting. All I had to do was isolate a couple of core muscles and work them until they were rock solid. "So long as your back and stomach are strong, you don't especially have to worry about the rest of the body," he said. He also wanted me to find a local water slide and take some practice runs. Easier said than done when you live in New England and it's winter. Ultimately, I committed to doing 50 sit-ups and 10 pull-ups each morning—a routine I remained fanatically devoted to for exactly eight days.

Still, I allowed myself visions of glory as I flew into Zurich and took a train across the German border to Hattingen, the tiny town where Scherer lives with his girlfriend, Sandra Westhoff, southern Germany's female speed-chuting champion. Scherer picked me up at the train station and drove us straight to the Aquasol water center, in nearby Rottweil. Facilities like Aquasol are quite popular in Germany, where long winters have people seeking out indoor exercise. Inside, there were saunas, hot tubs, lap pools, and a wicked four-story water slide Scherer called "the Black Hole." Added in 2003, it features a 394-foot tube, the longest in southern Germany. The interior is made entirely of black fiberglass and is illuminated with trippy flashing lights. As in any competition-ready chute, at each end there was a pair of laser triggers measuring times down to the millisecond.

Scherer, five-eight and lanky, toured me around wearing goggles and a snug, dark-blue Speedo-style suit tagged with the URL of Miller Ice Power, a nanotechnology company that had given him some experimental racewear. He had earrings in his left ear and a Celtic tattoo on his right calf. A marathon runner and fitness fiend, he got into speed chuting the year Aquasol opened its slide, when his mother pointed out an announcement for southern Germany's first championship in the newspaper. Scherer entered and won, as he has every year since. After capturing his first national title, in 2003, he has gone on to become a minor celebrity, appearing on German TV to teach Playboy Bunnies to speed-chute or to demonstrate how to somersault down a slide.

Despite his frequent use of Point Break–style bro slang, Scherer goes about chuting with a Teutonic seriousness. He sat me down in a plastic deck chair at the foot of the Black Hole and attempted to elucidate the physics of chuting. "It's all about the friction, dude," he said, rubbing his palms together. To go fast, I needed to minimize the surface area of skin and suit making contact with the slide. Basic speed-chuting position involves crossing your ankles, tensing your core, and arching your back so that there are only three points of contact with the slide: the shoulder blades and a single heel. Scherer lay down on the tiled floor and showed me how he throws his arms up behind him, clenching his triceps against his ears to keep his head up.

On the slide, the trick is to know when to maximize speed and when to dial it back. When Scherer comes around curves, his body is sometimes so far up the tube walls that he's looking down on the channel of water below. But if you ride too high in the wrong spot, you can stall, crashing onto your stomach and killing your run, if not sending you to the ER for stitches on your forehead. You also have to know how to manage the last 30 or so feet of the tube, when you reach top speed and even the most refined chuter tends to be out of control. Then there's the landing pool, which you want to enter with your legs tightly crossed. Hit it at 50-plus miles per hour and you'll be lucky if a nasal enema and a mouthful of snot are the worst of it.

Even when they do everything right, hard-bodied athletes aren't always the fastest chuters. Sometimes it's the cannonballs, 250-plus-pound behemoths like six-time national champ Christoph Feiden and perpetual runner-up Andreas Köhnke, whom Scherer refers to, with a hint of derision, as "the old-schoolers." They have bellies that drape over their Speedos, and they hurl themselves down slides with a single muscular heave. "They have no technique, just stomachs," says Scherer. Finally, there's a third group of sliders, to which I belong: the freaks. On my first ride down the Black Hole, I clocked a 22.39, a middling time some four seconds slower than Scherer's. Still, I was moving surprisingly fast, about 30 miles per hour by the end. By my tenth go, once I'd gotten a handle on how to arch my back, I was clearing the bottom laser in 20.35, a fairly decent time that had Scherer raising his eyebrows.

It turns out that my most substantial bodily flaws make me perfectly suited to speed chuting. My slightly hunched posture causes my shoulder blades to comfortably pop out like bobsled runners. My flat ass is easily suspended off the fiberglass. My bird legs cut a tight hydrodynamic profile. Even my love handles turn out to be an asset in a sport where having a little meat on the bones translates to faster times. I had just one physical disadvantage: the continuous tract of Semitic fur that runs from my lower back to my toes. After an especially dismal run of 21.71, I asked Scherer if my hirsuteness was slowing me down.

He bent over and took a close look at my thighs. "If you want to increase the speed, we'll need to make a shaving session this evening," he said. I chuckled uncomfortably. He didn't. "But, truly, if you keep your ass off the slide, it shouldn't matter," he added. For the sake of saving a few milliseconds, some of the most ambitious competitors shave or wax, but Scherer finds them needlessly vain.

My biggest problem was my baggy swimsuit. "You know, you're not going to win in those," he said, examining my trunks. In his quest for speed, Scherer has experimented with just about every possible form of swimwear, including the sharkskin-like unitards favored by Olympic swimmers and a type of low-friction foil he wrapped around his entire body. He's also coated his skin in soaps, oils, waxes, hydrophobic gels, and a kind of cream used to tenderize the udders of dairy cows—all of which are officially verboten in competition. But no matter: "There is simply nothing faster than bare skin," he says.

Even a few square inches of Speedo can cause unnecessary drag. As I stood behind him before a run late in our session at the Black Hole, he reached back and jacked the rear triangle up his crack like a G-string. "I'll see you at the bottom, man," he said. Then he dried his hands on a towel, leapt into the tube with an exaggerated mule kick, and slid down on nothing but flesh.

THE WATER SLIDE is such an obvious idea that it's hard to believe it was actually invented, like the lightbulb or the telephone, by a single individual in a single burst of inspiration. Even harder to believe is that it didn't happen until 1971. That was the year a California campground owner named Dick Croul, on vacation in Hawaii, rode a natural flume and decided he'd be the first person to build his own. He returned to Placerville, California, dug out a five-acre lake at his campground in the Sierra foothills, built a mound out of all the surplus dirt, and covered it with Gunite, the cement-and-sand mixture that lines swimming pools. Visitors to the campground rode the 350-foot slide on inch-thick gym mats.

From Northern California, Croul's invention spread rapidly to other campgrounds. All those early slides were made of Gunite, which meant they ripped up the back and could be ridden only on mats. Then, in 1976, Disney introduced the world's first commercial fiberglass slide, at Disney World's River Country, in Orlando.

The year after that, Wet 'n Wild, the world's first water park, opened in Orlando. The fiberglass slides—smooth, lightweight, modular—created an entirely new form of thrill: the body ride. Just man, water, and gravity. The late seventies and early eighties saw an explosion of highly questionable designs up and down both coasts. Infamously, Action Park, in Vernon, New Jersey, made the first attempt at a vertical loop-de-loop, with a long, straight tube that ended in a comically tight curlicue. A trapdoor had to be built into the top of the loop to rescue stuck sliders. Those who did make it around the bend sometimes had broken noses and other injuries to show for it, earning the place the nickname "Traction Park." The tube stayed open for exactly one month before it was shut down by the New Jersey Carnival Amusement Ride Safety Board. Likewise, in Singapore, a multi-lane racing slide sent riders several feet in the air as they crested a hill. Riders often landed on top of one another in the wrong lanes, and it was eventually closed.

The early slides were "basically bunny runs," says Rick Hunter, a former member of the Canadian national ski team, whose Ottawa-based company, ProSlide, is a global leader in the water-slide industry. "Now we understand compounding curves," he says. "It's like driving a race car. If you're going into a curve, you don't rip on the wheel; you turn slowly. We put you on the wall, shorten the radius, and hold you there."

ProSlide and its competitors have produced a number of stunning slides in recent years, the most expensive of which cost about $4 million to erect. At the Summit Plummet, a 12-story drop at Disney World's Blizzard Beach, even an unskilled chuter can top 50 miles per hour thanks to a 66-degree slope. Others, like the Wildebeest, at Holiday World in Santa Claus, Indiana, add features but require the use of inflatable rafts. The Wildebeest, the world's longest "water coaster," at 1,710 feet in length, includes sections in which riders are carried uphill with magnets. At the Blue Bayou Water Park in Baton Rouge, Louisiana, the Azuka, the largest "tornado" slide, drops riders 80 feet into a 70-foot-wide funnel, where they swing like a pendulum, experiencing weightlessness.

Of course, none of these slides was created with competitive chuters in mind. Hunter told me he'd never heard of German speed chuting. "Sounds pretty wild," he said.

Scherer dismisses most of the elaborate twisters crafted for the water-park masses. "I'm not terribly impressed by any of them," he says. Still, when a new slide opens anywhere in Europe, he's often called in to act as a test pilot. The week before I showed up, he had been at the Wave, near Innsbruck, Austria, trying out Wild Pig, the world's first double-loop slide. (The loops are tilted 45 degrees off vertical to prevent stalling.) The park's management sent him down with a box strapped to his stomach to measure G-forces on turns. In order to gain the approval of the TüV, a government-affiliated German safety organization, riders can't exceed 2.6 G's. Scherer says he topped out at nearly 6. "But since the people from the government can't go as fast as me, the slide is still considered legal," he explained.

Meanwhile, Scherer and other chuters have started building slides of their own. Recently, Scherer hired a carpenter to construct a small, perfectly vertical loop-de-loop, the first since Action Park's. His grand dream is to build a 900-foot kamikaze—taller than most Manhattan skyscrapers. He and his partner in the project, Rolf Allerdissen, another chuter, have been in talks with the government of Namibia about building the slide into the side of a major sand dune.

Last year, Scherer and his team built a mock-up of their Namibian kamikaze on a smaller industrial sandpile in Bavaria. After digging a trench down the 360-foot hill and lining it with plastic Slip 'n Slides, they brought in a local fire engine to pump water to the top. The first slider, a TV stuntwoman named Funda Vanroy, ended up flipping end over end and landing face-first at the bottom, bruised and with a bloody nose, having just missed getting decapitated by the boom of a video camera.

SCHERER HAD TO GO to work on my second day in Germany, so he sent me to the local sporting-goods store with Westhoff to buy a Speedo. He'd offered to let me borrow one of his own banana hammocks, but after witnessing his self-wedgie technique, I politely declined. Either way, he seemed deaf to the erotic undertones of my shopping for minimal-coverage swimwear with his girlfriend. But, having never worn tighty-whiteys, much less a Speedo, I needed the help.

After sorting through racks of dangling nylon suits, I selected a blue-and-white number and retreated behind a fitting-room curtain to tug it on. When I shyly pulled back the curtain, I asked Westhoff if I should maybe go up a size. She had me do a 360, pausing without humor to eyeball my junk, and shook her head.

That afternoon, Scherer and I went back to Aquasol. In my new suit I was immediately a full second faster than I'd been the previous evening, and my times dropped by a few milliseconds on each successive run. After two hours at the slide, our heels and shoulder blades raw, Scherer and I retired to the heated saltwater pool. "I want to show you something," he said as we relaxed amid a group of elderly women doing Aquarobics. He swam out into the middle of the pool, floated for a moment on his back, then began sinking.

"I don't float," he said, standing up again. "I can't explain it. I never have."

"Is that why you're so fast?" I asked.

"I really don't know why I'm the best. I often wonder," he said. "I mean, I use the same technique as all the others. I guess maybe it's my dense bones."

The next day, we took an eight-hour train ride across the country to Scharbeutz. The championship was being hosted by the Ostsee Resort and Spa, a five-star beachfront hotel. We checked in and hit the slide for practice runs.

Everything about the Ostsee tube was world-class. The curves were tight and nicely timed, the changes in grade were surprising, and the drop-off near the end was exhilarating. A technician had spent the week before the competition caulking every fiberglass seam with silicone to make it extra-smooth. Video cameras were installed in the ceiling of the tube so that a gallery of spectators could watch the chuters negotiate several of the course's more difficult turns on a bank of six screens.

For all that effort, I was pretty sure that about half the 117 competitors who'd shown up were there only because it sounded like a fun way to spend a weekend afternoon. The age range was impressive: The youngest entrant was eight; the oldest, 74.

Then there were the real competitors. Like golfers studying the greens before a major championship, we wanted to know those curves and banks intuitively. We kept anxious eyes on each other's times. "Let your butt hit the slide a bit," Scherer advised me. "You don't want the others to know your true speed."

There was a group of particularly amped guys whom Scherer kept referring to as the Weirdos. "It's OK to take water sliding seriously, but for these guys it's the meaning of their life," he told me. "The Weirdos are always saying, 'That guy is cheating!' or 'That guy oils his back!' They don't have jobs or educations. One of them is mentally disabled."

The Weirdos were easy to pick out. They were the ones hollering obnoxiously after good times and slapping the water with their palms and yelling "Scheisse!" after bad ones. One of them, on a practice run just before me, stepped up to the start position, dropped the back of his suit around his thighs, and launched his completely bare ass down the slide.

There had been bad blood between Scherer and the Weirdos ever since the group banded together to oust one of Scherer's close friends from the presidency of the German Race Sliding Federation, amid accusations of financial impropriety. Scherer countered by accusing one of the Weirdos of pedophilia. (The guy had e-mailed Scherer asking for pictures of some of the younger competitors.) Scherer tried, and failed, to have him banned for life from national competitions. He pointed him out as we waited in line at the top of the slide. "Stay away from that guy," he said. "He's Weirdo Number One."

In speed chuting, too much training can be counterproductive, because the more you slide, the more likely you are to bruise your points of contact with the fiberglass. When we went back to our hotel, I examined my damage in the bathroom mirror. I had a pair of red bull's-eyes on my upper back, surrounded by blue clouds of bruising. Scherer smirked when I showed him. "White skin, red cuts, blue bruises: very American," he said. His own left elbow was bleeding from a bang-up coming down off a high turn. Ralf May, one of Scherer's friends from Aquasol, had a hip so bruised he could barely walk.

Over beers at a traditional northern-German restaurant, I asked Scherer whether he thought I had any chance in the championship. "I'm not going to tell you you're going to win," he said. "I just can't do that. But it's possible you could make the finals."

He shrugged. "Anything is possible."

THE EVENT WAS SPLIT into three divisions: Women competed in their own group, and the men were put into welterweight and heavyweight classes, with the dividing line at 70 kilograms, or about 155 pounds. I swear that under normal circumstances my five-eight frame would be a fair distance south of that, but I'd spent the better part of the winter holed up with the shingles and overdoing the mini-muffins. At the official weigh-in, the digital scale put me at 66.7 kilos (147 pounds), which meant I was going to be one of the heaviest competitors in the welterweight class—a certain advantage. Even better, of the 17 competitors who'd registered as welterweights, three came in overweight and had been bumped up. My competition was 13 lanky teenage boys and an eight-year-old.

The morning consisted of three time trials. The ten competitors with the lowest combined time would then advance to the finals in the afternoon, where two more runs would decide the medal rankings. When Scherer's name was announced over the loudspeaker for his first slide of the day, the official timekeeper—a man wearing camouflage hunting pants hiked above his ankles, fluorescent orange suspenders, a cowboy hat, and aviator sunglasses—introduced him as "the most famous water-slider in the world." The crowd of three dozen spectators, arrayed on plastic deck chairs at the foot of the landing pool, hooted and clapped in rhythm.

My own introduction a few minutes later was no less raucous. As I stepped up to the slide, a German techno remix of John Denver singing, "Take me home, country roads..." blared through the sound system, a respectful if slightly confused nod to my home country.

After our three morning runs, Scherer was in first place in the heavyweight division and I was on my way to making my country proud, ahead of all the teenagers but one, a 17-year-old from Team Wedel named Jannik Ahrens, who weighed in a kilo heavier than me. At the top of the slide, as we prepared for our two deciding afternoon runs, I asked Ahrens if he thought that extra kilo accounted for the 18 hundredths of a second that separated us.

"I think it's this," he said, turning around. He popped his shoulder blades out. They protruded like a third pair of limbs. You could have hung a hat on each of them. He was a freak like me.

I got into position for my first run, looking over my shoulder at the line of welterweights waiting behind me, then up at the camera looking down at me. I took a deep breath. If I'd come all this way to Germany, I might as well go for it. I reached back, twisted the seat of my Speedo into a tight little rope, yanked it up my tush, then flung myself down the slide.

Halfway down, the water was spraying so hard up my nose that I couldn't breathe. My shoulder blades were burning. My ass was so far off the slide I could feel a breeze between my cheeks. Then, on the third-to-last turn, catastrophe struck. My mo­mentum carried me so high up the wall that I flipped and fell several feet before landing face-first on the tube, banging my arm on the way down. I rode the last two turns on my stomach before I was able to right myself. When I got out at the bottom, I looked up at my time: 22.51, a full second slower than Ahrens's slowest run.

Scherer, whose own gold was secure after a blazing first run of 18.54, was waiting at the landing-pool steps. He put his arms on my shoulders. "You need to relax your body more as you go around the curves. From now on there are no more errors. Rock the tube, Josh! Relax and rock the tube!"

As I climbed back up the steps to the top of the slide, those words rang in my head. I went G-string again, but this time I let my body go limp around the turns, and I could feel myself accelerating even faster than on my previous run. Just as I was about to flip on the same turn that had done me in, I spread my legs slightly and managed to stay upright. At the end of the tunnel, there was a moment of quiet, then I hit the pool and German techno exploded in my ears. When I climbed out, my legs were shaking. I looked up at Scherer, who flashed me a pair of shockers and pointed excitedly up at my time: 21.93 seconds. Still second place behind Ahrens but a righteous finish. I wrapped a towel around my waist and pumped my fist for the cheering crowd.

A podium was brought out. Cameras flashed. A middle-aged blonde in pantyhose and flip-flops hoisted a plastic chalice emblazoned with the logo of the Ostsee Resort and Spa and handed me a certificate. For my second-place finish, I received a snack basket filled with German delicacies: herring fillets in tomato sauce, a box of muesli, a jar of pickles, pea stew, and bockwurst sausages. I left them in my hotel room, along with my wet Speedo.