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Performance
First Responder
In the ever diversifying world of outdoor sports, we all hit a few road blocks en route to peak performance. First Responder, a column in our new Performance section, seeks to demystify the everyday snags that miff your game. By Thomas Berenato and Mary Anne Potts

Q:

I'm going on a 13-hour flight. Should I worry about "economy-class syndrome"?

Deep venous thrombosis (DVT), a blood clot that develops in the lower leg after prolonged periods seated in cramped quarters, first gained headlines and the media-friendly nickname "economy-class syndrome" in the mid-1980s. Travelers took note. Each year, hundreds of thousands of Americans develop DVT; many of them die from its complications. But a report published last spring by the British Medical Association (BMA) says that DVT is not exclusive to air travelers; a person riding in a car or even sitting at a desk for an extended period of time may be just as likely to form a blood clot as someone flying on a plane. The good news? All airplane passengers—regardless of ticket price—have enough legroom to prevent clots. "Everybody who plans to be immobile for a long period of time should be aware of DVT and take the necessary precautions," says Annette Ruge, head of the BMA's Aviation Health Unit. So what can passengers do to avoid getting clots? While travelers wait for the World Health Organization's set of recommendations (expected in early 2005), the American College of Chest Physicians advises using the new anticoagulant fondaparinux, which it says is safer and more effective than aspirin or heparin at combating clots. Other tips: Stay hydrated and perform leg exercises in flight—such as extending your ankles and flexing your buttocks.

Q:

Is there a good way to limit lactic acid buildup during a day on the slopes?

"Actually," says Graham Lamb, Ph.D., a scientist at Graham Lamb in Melbourne, Australia, "our study indicates that the buildup of lactic acidity inside the muscle fibers helps prevent a major cause of muscle fatigue." Wait a minute. How does that jibe with lactic acid's most notorious effect—sore, tired legs? When Lamb and a team of researchers looked at muscle fatigue from a molecular level, they found that during intense exercise, potassium, which is excreted from the active muscle cells, short-circuits the electrical signals relayed from the brain that tell the muscles to move. In response, the body surrounds the muscle cells with lactic acid, a conductor that allows them to continue receiving messages. "[The] results suggest that high, steady states of intensive exercise can be maintained longer due to the protective effect of lactic acid," says Thomas Pedersen, a member of Lamb's team.
But just because lactic acid may be good for you doesn't mean it doesn't burn like crazy. Three years ago, Carl Holmes, a former competitive triathlete, financial analyst, and sometime chemist, came up with SportLegs, a calcium and magnesium-lactate blend that, he claims, "enhances the body's lactate transfer system." Preliminary tests were encouraging. "We tested it during incremental exercise to exhaustion," says Ellen Glickman, Ph.D., professor of exercise physiology at Kent State University, who expects more comprehensive results in December. "Those who took it had a higher lactate production and were able to work out longer, but it's still somewhat of a mystery why that happened." Until those results are in, stick with the reliable burn-fighting method of two aspirin and a massage.

Q:

I know that what you eat can have an effect on muscle mass and strength, but can it affect cardio, too?

"Absolutely. Foods that are naturally high in vitamin C—like citrus and tropical fruits or tomatoes—increase nitric oxide levels in the blood that dilate the arteries, so that you get better flow to your muscles; that means they can do more, longer and faster," says Leslie Bonci, director of sports nutrition at the University of Pittsburgh Center for Sports Medicine. But stocking your cabinets with supplements alone is limiting. By eating the actual foods, other beneficial compounds come into play, such as phytonutrients, which further improve blood flow. Dark chocolate (Don't get too excited; Bonci recommends no more than an ounce a day), apples, onions, and tea produce a similar effect because they contain flavonols, a type of antioxidant, which also dilate arteries. "Because these solid foods first must be digested, you'll need to consume them two to three hours prior to your workout to glean the full effect," says Bonci.


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December 2004/January 2005



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