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    Hold Your Breath – You’ll Need It For Freediving

    Minutes can seem like an eternity to intrepid freedivers, who like to join the denizens of the deep on their own terms.
    The day he took his first freediving lesson, Dr. Erik Seedhouse, held his breath for an unexceptional 90 seconds. Twenty-four hours later, using techniques practiced by elite divers, his time increased to two minutes and 50 seconds. A remarkable physiological leap, but a modest achievement when measured against the sport’s official world records of eight minutes, eight seconds for men and six minutes, six seconds for women.

    Dr. Seedhouse, co-director of extreme physiology at Simon Fraser University in Vancouver, conducts a unique ongoing study monitoring changes in physiology among participants, before, during and after their 12-week introduction to freediving. Ideally, results should benefit people with bronchial disorders, pulmonary and respiratory problems and sleep apnea.

    “Students start out holding their breath for 80 seconds. By the end of the course, they’re up to five minutes,” says Dr. Seedhouse, whose book, Performance FreeDiving, (Human Kinetics), co-written with Canadian freediving coach, Kirk Krack, will be available in January 2004.

    Humans aren’t the only mammals capable of holding their breath—studies suggest monkeys and dogs do too; however, we’re the only ones volunteering for the experience.

    There are several forms of competitive freediving. In its purest, constant weight freedivers don flippers with three-foot-long fins, hyperventilate to reduce carbon dioxide, “pack” air into their lungs and digestive tracts, clamp shut their nostrils and on the strength of a single breath, descend head first to previously unimaginable depths.

    The mammalian diving response kicks in, relaxing body function and diverting blood; your heart slows significantly, your chest contracts and you fight the involuntary impulse to breathe. At fifty feet, you sink without effort. Drowsy but alert divers report the cold feel of oxygen in their bloodstream as they share in the “Zen” consciousness of floating unencumbered among a variety of species in an atmosphere not our own.

    Ascent can be perilous. Shallow water blackout—the brain’s response to a shortage of oxygen in the blood—occurs without warning, usually within 15 feet of the surface. The same levels of reduced oxygen can paralyze legs when they’re most needed to combat the enormous external and internal pressures being exerted.

    Despite freediving’s perceived dangers, Dr. Seedhouse says, “Virtually 99% of fatalities are a result of human error. Follow the guidelines, follow regulations and you’ll be fine.”

    So You Want to Swim With the Fishes?

    *Take a course taught by a qualified professional. If you have any doubts about your health, consult your doctor first.
    *Don’t be unnerved by the sport’s more alarming statistics, says Dr. Seedhouse. “Most involve spear fishermen who are doing multiple dives a day. When you do that you’re courting problems. Top freedivers are careful about how many dives they do and the circumstances under which they do them.”
    *Never dive alone. Your eardrums can rupture; narcosis is a possibility and some divers experience unexplained heart arrhythmia during dives.
    *Top divers are in peak physical condition, have huge pulmonary capacity and an ability to reduce cardiac activity. Many of them do stretching exercises, and practice Yoga, visualization and hypnosis. Follow their lead. Oh – and cycle.
    *Unlike scuba divers, freedivers can surface right after a dive
    *Stick to conservative depths. Fifty feet is considered safe. The deeper you go, the riskier it gets.
    While many of us would like to swim like a fish and feel free as a bird — freedivers know how it feels to do both. For more information, go to the International Association for the Development of Freediving site at www.aida-international.org