Depth Chargers

To most people, AIDA means Verdi's opera, sung by stars with big lungs and finely tuned ears. To a growing group of extreme sports enthusiasts, however, AIDA is an acronym for something else, although outstanding lungs and ears are also what count. They are not divas but divers, their sport being to go as deep underwater as is humanly possible on a single breath of air. AIDA is the Association Internationale pour le Developpement de l'Apnee, the latter from the Greek apnea, or cessation of breathing. Its members also call themselves free divers because they do it like fish, without tanks of air.

Extreme sports such as rock climbing, base jumping and parachuting are booming among risk addicts around the world, but few are more challenging, or dangerous, than free diving, an extension of the ancient custom of gathering food, pearls and treasure from the sea floor. According to Italian champion Umberto Pelizzari, the rewards of free diving--depicted in the Luc Besson film The Big Blue--outweigh the risks: "You are in another world, where there is no gravitational force, no color, no noise ... one does not descend in apnea to look around but to look into oneself. It is a long jump into the soul."

Off Sardinia last October Pelizzari lowered the world record to 150 meters. Picture three Olympic swimming pools stacked vertically: down and back up on one lungful. Not so long ago it was thought that submarines, let alone human chests, would implode under the pressure at such depths. Pelizzari added 12 m to the mark set by his countryman Gianluca Genoni. Then last week, Pelizzari's rival Francisco ("Pipin") Ferreras, a Florida-based Cuban, shattered the magic 150-m barrier: on his 38th birthday, he reached 162 m, off Mexico, in 3 min. 12 sec.

These feats were in the category free divers call no-limits, where the descent is made riding a "sled," a weighted device which runs down a taut cable held on the seabed. Once at his or her limit, the diver opens an air valve to inflate a lifting device, like a big balloon, then rushes back to the surface, hoping to reach it before blacking out. Because they don't use compressed air, free divers can surface rapidly without risking the "bends," the build-up of nitrogen bubbles in the blood that divers with tanks must guard against.

Sardinia-based Pelizzari, 34, was so afraid of water as a child that he hated going into the shower. But he has developed his mind and his 84-kg, 189-cm body to such a state that he has held his breath for an astonishing 7 min. 2 sec. in static apnea, meaning motionless in a pool. The only person to have bettered that mark is French free diver Andy Le Sauce, whose world record is 7 min. 35 sec. Pelizzari has a lung capacity about a liter above average, but says this is not crucial. "More important are your ears, your muscles and your mental preparation. Some people's ears won't stand the pressure that builds as you go down, so no amount of lung capacity will help. Your muscles should be long and thin to consume less oxygen, allowing precious extra seconds underwater. You also have to banish all fear, worries and distractions, because they also consume energy."

The most-respected category among free divers is called constant-weight. In this, the fixed cable is only for visual guidance, and equipment is restricted to flippers, wetsuit and goggles. Divers can carry whatever weight, but then must bring it back to the surface, unassisted by a lifter bag. Just a week before his 150-m no-limits dive Pelizzari set a new world mark of 80-m for this "pure" category. Then in November, 35-year-old Hawaii-based American Brett LeMaster--whose e-mail address appropriately begins n2deeph2o--pushed the record to 81 m in the Cayman Islands.

The Caymans are also home to the world's best woman free diver, Tanya Streeter, 27. She holds the women's record in the constant-weight class (67 m), and is approaching the best of the men in no-limits, having reached 113 m. Daughter of a British mother and an American father, Streeter also holds the record for a category called free immersion (freshwater), in which the diver pulls down a line using only the arms. She reached 55 m in a cavern in Florida--3 m deeper than the men's record set by Belgian Jean-Pol Franois.

Although she has a way to go to catch the likes of Ferreras, Pelizzari or LeMaster in the main categories, Streeter thinks there is no physical reason why a woman shouldn't go as deep as a man. "In fact, we have lower metabolic rates and higher pain thresholds, and I think we are quicker at realizing our limits than men are," she says. She had hoped to try for 122 m in the no-limits category next month, but hasn't found sponsorship: about $35,000, to cover training, judges, safety divers and equipment.

She and all free divers have to continually "equalize" their ears--by pinching the nose and blowing out--to compensate for the increasing pressure which otherwise would rupture their eardrums. Their heart rate can drop to as low as 10 beats a minute, and their lungs squash to as little as one-sixteenth of normal size. "The lungs are like a balloon shrinking," says Streeter. "As the chest wall collapses, fluid, basically blood, is sucked into them. It used to be thought that your ribs would implode and crack, but they are more flexible than that. The only place where there's air is in your airway and sinuses, which is painful because they too are shrinking under the increasing pressure."

At last year's world championships off Sardinia there were 15 blackouts and one heart attack. But, because of the adrenalin rush or the soul-searching Pelizzari refers to, the sport is growing. The president of Lausanne-based AIDA, Sebastien Nagel, says it has links with 40 countries and estimates there are 5,000 free divers around the world, excluding people who spearfish. Brett LeMaster says he does it "simply because I love the sea." He plans to try to go deeper than his 81-m constant record, "until I find my limit, wherever that may be."

Nagel says there are two essential rules for those who want to learn the sport: "Never practice alone, and never practice with someone who is inexperienced. The only safe way to practice free diving alone is without water! Even for champions. And it's very good training." He's referring to the yoga and other breathing exercises free divers do, along with lots of running and gym work.

Most people would rather lie in a hot bath listening to Verdi, but free divers are drawn to depths by the same magnetism that makes climbers scale heights. Just invert Mount Everest, and melt the snow.

With reporting by Martin Penner/Rome