Late last month, after I'd finished a nearly three-mile jog and stopped by the YMCA to lift free weights, I lay sprawled on a deck chair watching my two youngest children splash in their wading pool. The temperature flirted with 95 degrees.

"Mommy, can we go inside?" my 4-year-old asked after a few hours.

"How about 15 more minutes?" I protested, breathing in deeply.

A year ago I would have raced for the shelter of our air-conditioned house. My 42-year-old asthmatic lungs would have rebelled at merely opening the front door and walking a few steps in the summer heat and humidity. But now I run, skate, bike and hike outdoors, no matter how high the mercury or thick the air. And my lungs are just fine, thank you. No coughing, no airway-closing spasms, no feeling faint from lack of oxygen, no hiding in bed sucking on an inhaler to jump-start my breathing.

All this, I believe, because I added a new tactic to my battle with asthma. Last August, I committed to a three-times-weekly physical conditioning program that I designed with my doctor's blessing.

Has it been proven that exercise helps asthma, a chronic airway inflammation that affects nearly 22 million adults in the United States? No, says James Kiley, director of the division of lung diseases at the National Heart, Lung, and Blood Institute. Evidence is still lacking "that exercise itself will directly improve asthma or modify the underlying respiratory impairment," he says. "At this point, there are relatively few high-quality clinical trials that have been conducted to support this concept."

That's why the guidelines for the institute's National Asthma Education and Prevention Program stop short of prescribing exercise; instead, they recommend that asthma be well managed so patients are able to exercise. But that recommendation could become much more specific if research confirms what some preliminary studies suggest. (A complicating factor is that for an estimated 10 to 15 percent of the population, vigorous physical activity can trigger asthma symptoms.)

A review of nearly 40 studies (most small, none blinded and only about 15 controlled) in the May 2005 Journal of Allergy and Clinical Immunology found that asthma patients who took part in fitness activities three to five times per week over 18 weeks "used less medication, had fewer doctor visits and reported decreased exercise-related fear and anxiety and less absence from school and work" than before starting their exercise routines. The review also cited growing research blaming inactivity as a factor in the increase of asthma prevalence and severity: According to the Centers for Disease Control and Prevention, newly reported asthma cases doubled from 1980 to 2002; asthma-related doctor visits and hospitalizations have also increased, with the former doubling between 1979 and 1992.

The American College of Allergy, Asthma and Immunology (ACAAI), among other groups, cautiously recommends exercise to asthma sufferers, saying on its Web site, "Regular exercise is beneficial for everyone, and may be particularly helpful for individuals with allergies and asthma." The key word here is "cautiously." Exercise intensity and tolerance vary by individual and asthma type: What might be helpful for a patient with allergic asthma, for example, might be risky for someone with exercise-induced asthma, where the response to physical activity requires close medical monitoring. In each case, any change in habits should be made under a doctor's supervision.

Pushed Into Action

I might have continued my religious avoidance of exercise and dependence on medication, too often sucked down in emergency rooms, had events not intervened. Last summer, a sudden sensitivity to oral medications forced me to give up Singulair, my asthma drug of choice. Without it, I needed inhalers several times a day.

I remembered a conversation I'd had with the mother of two asthmatic teenagers in my oldest daughter's ballet class. She'd told me how their doctor had encouraged dance as an exercise that would help her children's lungs and described how they performed demanding routines without ever seeming breathless.

Could that work for me? My doctor, Fernando DeLeon, a Baltimore-based pulmonologist, agreed it was worth a try.

Better breathing for people with asthma involves two things: decreasing exercise-induced panting, and treating underlying airway inflammation, says Norton A. Elson, a pulmonologist at Washington Adventist Hospital. Exercise training, says Elson, may boost breathing efficiency and oxygen intake while placing less demand on lungs and circulation.

That's consistent with the findings of some small studies. A 2000 study in the journal Chest showed improved pulmonary function for asthma patients after a 10-week aerobic conditioning program. Compared with controls, the five asthma patients moved larger amounts of air in and out of the lungs, and decreased their exercise-induced rapid breathing. An earlier study out of New Zealand produced similar results. But the studies' small size and weaknesses in design have called the findings into question.

According to Carlos E. Picone, chief of pulmonary diseases at Sibley Memorial Hospital, exercise may also boost functional reserve -- allowing well-conditioned patients, over time, to handle more activity and experience fewer problems.

The mechanism by which exercise may help asthma is not clear, according to Elson, although evidence suggests that it may involve a reduction of airway inflammation.

Although DeLeon couldn't guarantee that conditioning would provide noticeable relief, I felt it was worth a shot. What did I have to lose?

An Exercise Convert

I was one of those girls who copped out of high school PE class with the trusty "cramps" excuse. I never owned a pair of sweat pants. I didn't sweat.

Still, I headed for the Y. I started with a mere five minutes on the treadmill, where my rapid panting resembled an obscene phone call. Following doctor's orders, I rested or slowed down if I experienced chest tightening or shortness of breath, and I always carried my inhaler.

Every other day, I increased my treadmill time by two to five minutes. Soon, I needed fewer breaks and was able to walk briskly for 20 minutes without discomfort. I began to enjoy the new morning routine.

Help came from surprising quarters. One day, as I swung five-pound free weights in the air trying to tone my skinny arms, a fellow exerciser had seen enough. "I can't watch this anymore," she said, showing me how to anchor my elbows firmly to my waist while lifting slowly.

My pace improved as I added more treadmill time. An avid runner glanced over one day and congratulated me.

In late October, nearly four months after this sweaty odyssey began, I broke into a solid run, from 4 to 6 miles per hour. Okay, so it only lasted two minutes, but it was a run nonetheless. Over time, I worked up to 45 minutes on the treadmill, alternating walking and running.

Around mid-November, I noticed more subtle changes. Housework no longer provoked respiratory fits, just a sneeze or two. My breathing was less labored. Call me crazy, I even took the vacuum for a spin or two several times a week. I planted a vegetable garden, weeding and sweating in the soupy July air. I began to run and play outdoors with my four children. And as a bonus, fitness conditioning also helped me shed about 10 percent of my body fat and dampened my cravings for junk foods.

DeLeon is history -- haven't seen him since last August. He's pleased by my improvement -- I haven't needed my inhaler in more than six months, and I'm no longer dependent on other medications. He recommends that I keep up my new level of physical activity. I plan to. The future, of course, is impossible to predict, but for now, I'll take every deep breath I can get and enjoy.


Jacqueline M. Duda is a Washington area freelance writer.

Poor asthma control and over-dependence on an inhaler, above, can take the fun out of seasonal activities. Research suggests regular exercise may bring asthmatics relief.An illustrated cross-section, above, of a bronchial tube, or air passage, shows the swollen lining characteristic of asthma.