Athletes On the Edge: Sword Swallowers, Arctic Swimmers, and Human Cannonballs

They won't be in the Olympics, but extreme athletes also perform at the highest levels of skill and athleticism.

By Leaundra TemescuAug 13, 2008 5:00 AM
Mark Toorock | Image courtesy of


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The Human Alley Cat traceur Mark Toorock

If you watched the 2006 James Bond flick Casino Royale, you saw the sport of parkour in the opening chase sequence. If you didn’t make it to the theater, just imagine a rubber ball bouncing through a city, off walls, trees, banisters, buildings, fire hydrants, and rocks. Replace the ball with a person, climbing over 10-foot walls in seconds, vaulting over cars, and leaping from roof to roof, Matrix-style—now you have the concept of parkour. Mark Toorock, one of the world’s best-known practitioners and the owner of what may be the world’s only dedicated parkour training gym, explains, “People who practice parkour see the law of gravity as more of a suggestion than a limitation.”

Called traceurs after the French word for “tracer fire” (a connection this writer is still trying to understand), Toorock and other top practitioners follow a unique training program that is one of the most comprehensive in all of sports. Par­kour requires a finely honed combination of speed, strength, balance, endurance, agility, accuracy, coordination, and timing.

Initial training is heavy on conditioning and learning basic moves like the cat balance, pop vault, and cat jump; feline behaviors, minus the hair balls, figure prominently in this sport. To develop strength, endurance, and balance, Toorock has his advanced trainees do crawling pushups—lowering the chest to the ground from the all-fours position, then crawling forward one step—all the way around the block, about a quarter mile. Jumping off boxes helps traceurs develop techniques like the roll, which distributes the force of landing so that joints are protected from the shock of hitting the ground from an eight-foot leap. Trainees perfect balance and fortify core strength by standing on balance beams in a circle and throwing medicine balls at each other. Many of the most advanced traceurs also train in acrobatics.

The Ice Queen Endurance Swimmer Lynne Cox

Lynne Cox has always had an extraordinary ability to produce heat. So what does she do with this unique physiological gift? She swims in the coldest water she can find, wearing nothing but a swimsuit, goggles, and bathing cap. And we don’t mean cold like the winter dips taken by the crazies at the local Polar Bear Club. We’re talking cold cold like in the Arctic Circle, where Cox swam for 23 minutes—a little over a mile—in the Baffin Sea, dodging icebergs all the way. The water measured 28.8 degrees Fahrenheit, a temperature that would render most of us unconscious in less than 15 minutes. Cox attributes her unique abilities to three essential characteristics that enable her to maintain an unusually high core body temperature, even in the most frigid conditions. More than most people’s, Cox’s vasculature responds to the cold by limiting how much warm, core-temperature blood gets sent to the extremities, where it would cool more rapidly. Her large muscles enable her to exercise hard enough to produce more heat than she loses. And her even fat distribution acts as a thermal blanket.

Even so, Cox must train to avoid sharing Leonardo DiCaprio’s fate in Titanic. When she was growing up, she wore only lightweight clothing year-round and slept with the windows open in the winter. Later, she sprinted in her parents’ backyard pool when the water was about 50°F. Whereas most long-distance swimmers train for endurance, for her cold-water swims Cox must train for speed so she can get out of the water as quickly as possible. According to Cox, because so much heat is released through the head, she must swim with her head out of water. Doing so pushes her hips down and creates drag that must be compensated for by a powerful upper body. Cox’s strength training includes thrice-weekly yoga, Pilates, and free-weight workouts. To prepare for the sudden rush of adrenaline when she hits the frigid water, she takes Spin classes to condition herself to hyper heart rates.

The final step? “I treat my body like a thermos. Right before the swim, I drink four eight-ounce glasses of warm water,” Cox says.

The Gag Artist Sword Swallower Charon Henning

The body’s intense and altogether understandable aversion to having a steel spike stuck down the throat is the greatest challenge facing Charon Henning, a renowned sword swallower. She initially trained for more than six months with a master sword swallower to be able to insert a blade into her mouth, past the larynx and pharynx, through the esophagus, and into the stomach. Learning how to position her torso so that all those parts were lined up for a straight shot down took about two weeks. After that, she trained to ignore four natural gag points: the initial taste, the back of the throat, the entrance to the esophagus, and the esophageal sphincter (the entrance to the stomach). Now she has mastered the trick well enough to travel around the country, amazing and horrifying audiences at fairs, circuses, and parties as she swallows a 23½-inch-long, ¾-inch-wide blade, the highlight of her act.

Practice and mental focus allow Henning to control the powerful gag reflex, which cannot be completely suppressed. Daily yoga helps her maintain the correct alignment of her throat, esophagus, and stomach. Proper gear maintenance is also key. Like any high-performance athlete whose success depends on the quality of her equipment, she checks her swords before every swallow by running her lips over the blades to feel for spurs and splinters that could perforate her insides.

Diet is another very important part of Henning’s training regimen. The day before her show, she eats peanut butter sandwiches washed down with small amounts of liquid. This slow-moving, globular food stretches out the esophagus. Before her performances, she also downs high-protein foods like meat to deal with the acid and insulin secreted by the stomach and pancreas, which apparently don’t realize that she is swallowing a sword rather than a yummy snack. Henning spends several hours in the gym each week combating the inevitable consequences of her high-fat diet.

Jaws of Steel Competitive Eater Crazy Legs Conti

Winning an eating contest ultimately comes down to jaw strength. When you’re consuming 45 burgers or 24 dozen oysters in 8 minutes—and Crazy Legs Conti has done both—the ability to chew and swallow quickly is what separates the merely gluttonous from the true gurgitators, the champions of competitive eating. It’s what Conti noticed in Takeru Kobayashi, the legendary hot-dog champion, when this lean young Japanese man consumed 50 hot dogs in 12 minutes at Nathan’s Famous Fourth of July hot-dog eating contest in 2001. (In 2007 he was up to 63.) It also inspired Conti to take eating seriously as a sport.

To build the requisite mandible power, extreme eaters chew bubble gum and gnaw frozen Tootsie Rolls. But Conti, 2007 world champion in corn-on-the-cob eating (34¾ ears of corn in 12 minutes), insists that the winning factor is not just molar force—it’s technique. He charts the movement of his chewing and swallowing, even practicing with music to get into the proper rhythm: Irene Cara’s “Flashdance” is a good beat to eat by, he reports. Manual dexterity is also critical, especially with foods that require implements, such as oysters, or precise handling, like corn on the cob. Conti does finger push-ups to ensure his digits have the strength to go the distance.

Yoga has an important place in Conti’s training protocol. It helps him focus and teaches crucial breathing techniques that allow him to stretch his stomach to its full capacity. Regular workouts at the gym help him control his weight. The most obvious irony of this sport is that the best eaters are often the scrawniest. Conti speculates that’s because excess subcutaneous fat would compress the stomach, making it difficult for it to perform the accordion act needed to accommodate copious intake.

Mental discipline is also key. In the heat of competition, fighting the “urge contrary to swallowing” is the most grueling obstacle, Conti says. Only those with iron discipline over their body’s natural reactions survive. This sport is not for the faint of heart or—needless to say—weak of stomach.

Human Cannonball David Smith Image © Canadian National Exhibition/William Smith | NULL

The High Flier Human Cannonball David smith

Take it from David “The Bullet” Smith, the world’s highest-flying human cannonball: “It’s easy to fly through the air. You don’t need any training for that. It’s the landing that matters.”

Smith developed his balance and agility at a young age. He was trained as an aerial artist in a family of circus performers, where he developed the flexibility and reflexes needed to fly through the air with the greatest of ease. When he began blowing himself out of cannons, the ability to land safely became slightly more relevant. Walking away from a shot that propels him more than 80 feet in the air at a speed of more than 70 miles per hour for a distance up to 180 feet requires firm control. While in midair, Smith must make rapid adjustments and complete a precise half somersault so he lands on his back. He won’t divulge exactly how the cannon works (it’s a family secret), but he does admit that his body endures a force of 9 g’s at takeoff and 12 g’s at landing. Early trapeze work, combined with track events and weight lifting in high school, helped him build a powerful upper body. Such strength is critical not only for the landing but also for maintaining consciousness during blastoff.

The mental challenges faced by a human cannon­ball are huge. Smith emphasizes there’s no way not to get nervous when you are climbing into a cannon. Instead, you have to be tough enough not to be distracted by your anxiety. Mental prowess is a prerequisite in another respect: You have to be good at math. A successful shot—defined as one you survive—demands precise and complex calculations of barrel angle, wind speed, temperature, distance, weight, overhanging tree branches, etc. According to Smith, “You need to get an A on every shot. Cs are bad. We won’t even talk about Ds.”

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