PUBLISHED 08/16/2006
Dan Houston, 49, occasionally suffered from hay fever, yet his allergies never affected his ability to run. That changed in July 2004 when he began having trouble breathing during a routine six-miler. "My lungs felt like I was inhaling very cold air in the middle of winter," says Houston, a department manager for a machinery manufacturer in York County, South Carolina. Houston struggled to run that summer and the next. "It was hard to justify taking medication just so I could run," he says. "But finally I decided that exercise was important enough to me to seek help."
Houston's doctor diagnosed him with exercise-induced asthma (EIA), a condition in which exercise triggers coughing, wheezing, shortness of breath, and chest tightness. (Chronic asthma is a more serious affliction.) Today, Houston takes two puffs from his inhaler about 10 minutes before he works out and can, on most days, run without gasping.
EIA and hay fever (or allergic rhinitis) are the two most common respiratory conditions that affect runners, and they often go undiag-nosed and untreated. But as Houston found, it only takes a little effort to manage your symptoms so they don't slow you down.
Respiratory 101
Although allergies and asthma are separate conditions, they often go hand-in-hand. Everett Murphy, M.D., a pulmonologist in Olathe, Kansas, says about 20 to 40 percent of his patients with EIA have some form of allergies.
Allergies occur when the immune system overreacts to substances that are harmless in most people. "In these individuals, the body produces IgE antibodies to the allergen," says Marjorie Slankard, M.D., a clinical professor of medicine at Columbia University and codirector of the allergy clinic at Columbia/Eastside Hospital in New York City. "Those antibodies then cause certain cells to release histamines and other chemicals, including leukotrienes." Histamines are the bane of allergy-sufferers' existence, causing symptoms that range from a runny nose and itchy eyes to difficulty breathing.
When we breathe, air travels through the nose or mouth, through the windpipe into two main air passages called the bronchial tubes, then into tiny airways in the lungs. For most of us, this process is effortless. But if you have asthma, those airways become inflamed and swollen, making breathing difficult and the passages overly sensitive to allergens (trees and grass) and irritants (smoke, dust mites, and indoor molds).
So what makes exercise a trigger? One theory is that those with EIA are overly sensitive to the temperature and humidity of the inhaled air. Also, during exercise, you're inhaling more air per breath than when you're sedentary. "When a runner increases his breathing rate and depth, the cooling and drying of the airway seems to trigger the EIA response," says Dr. Murphy.
Interestingly, studies have shown that following most EIA attacks, there's up to a two-hour period during which exercise won't spur another attack. So those who can manage to run through the initial onslaught of symptoms can finish their runs in peace.
