By Shelly Wilson, with Dr. Christopher Randolph
Christopher Randolph, MD, is the Chairman of the Sports Committee of the American Association of Asthma, Allergy, and Immunology (AAAAI). He has a private practice in Waterbury, Conn. Shelly Wilson is an Assistant Editor at Training & Conditioning.
Training & Conditioning, 10.7, October 2000, http://www.momentummedia.com/articles/tc/tc1007/breath.htm
At the start of every cross country practice, especially on the coldest days, there’s one athlete who just can’t catch his breath. He shows most of the signs of being out of shape—fatigue, shortness of breath, wheezing, and coughing—but you know he’s spent most of the off-season training hard. His coach grumbles about conditioning, but you suspect something more insidious—exercise-induced asthma, also known as EIA.
A common disorder whose prevalence and potential severity are often overlooked, EIA can and does affect performance. Many clinicians also believe it is a red flag indicating a more serious condition—chronic asthma. And, in addition to the well-known dangers of this disease, it has now been shown that, left untreated, chronic asthma can cause permanent scarring of the air passages.
In the following interview, Christopher Randolph, MD, a board-certified allergist/immunologist and pediatrician, explains what exercise asthma is and the importance of its diagnosis. He also discusses the occurrence of exercise asthma among athletes and offers steps athletic trainers can take to identify sufferers, deter the onset of symptoms, and help ensure optimal athletic performance.
If an athletic trainer saw an athlete suffering EIA on a given day, what would he or she observe?
Almost certainly, after the athlete exercises for five to seven minutes vigorously, he or she will develop a cough, wheezing, and/or chest tightness. There will be definite respiratory symptoms that develop within a half hour of that five to seven minutes of exercise and those symptoms can continue for an hour to two hours after exercise is completed.
What is it about exercise that brings on this condition?
That is a matter of dispute, and there are two different schools of thought. But, ultimately, inhaling cold or dry air through the mouth triggers it because you don’t get the humidification the nose provides.
Cold air through the mouth results in a reactive hyperemia, or increased blood flow, in the airway. Because the airway is so cold, the body tries to rush warm blood into the area. In the process, the airway swells up because the blood vessels get bigger, and when they do, they obstruct the airway.
The other thought is that dry air triggers EIA. In the airway, we have allergic mast cells. If you have dry air that comes in, those allergic cells are placed into an environment where there’s not enough water. And, remember that all cells have to be in a certain amount of saline to survive. So if you put the cells in pure dry air, without fluid, they shrink, break, and release their chemical mediators—histamines, leukotrienes. These chemicals cause your airway to go into spasm and produce the wheezing and the cough.
If an athlete were to breath through his or her nose, he or she could eradicate exercise asthma. But high-performance athletes breathe about 20 to 30 times the normal volume of air and the nose can’t accommodate that. So they breathe through their mouths and inhale the cold, dry air that triggers EIA.
How prevalent is exercise asthma among the athletic population?
A study just published in the Journal of Allergy showed that 22 percent of U.S. athletes in the 1998 Winter Olympics had exercise asthma. Therefore, the logic is that most high-performance athletes would follow the same pattern—that at least one in five have exercise-related asthma. The reason we’re seeing so much asthma in athletes is no big surprise. It’s because they are the people who most challenge their pulmonary resources.
It’s estimated that 18 million individuals in the U.S. suffer from asthma, and about 5 million of those are under the age of 18. Are certain individuals more likely to suffer from this condition?
Far and away, most people—around 90 percent—with chronic asthma have exercise asthma, so if an athletic trainer has an athlete who already has an asthmatic condition, that athlete will almost certainly have exercise asthma. The second group are those with allergic rhinitis (hay fever). Forty percent of the 35 million people in the U.S. who suffer from hay fever will have EIA. And in our studies, about 10 to 15 percent of the general population will have exercise asthma.
The bottom line is that somewhere between one in two and one in 10 of all the athletes an athletic trainer sees will have exercise asthma.
In which sports are athletic trainers more likely to see EIA?
Sports like wrestling, baseball, football, and golf are characterized by short bursts of energy and are less likely to trigger EIA than sports requiring continuous activity, like soccer, basketball, field hockey, and cross country running.
Also, cold-air sports lead to more and more identification of asthmatics. And here’s a striking statistic: 50 percent of high-performance athletes who compete in cold-weather sports, like cross country skiing, will have exercise asthma.
Why are the recognition and diagnosis of EIA in individuals so important?
It’s critical because American clinicians believe that exercise asthma is only the tip of the iceberg—that EIA is really an indicator of ongoing chronic asthma. And that’s probably the most important thing about it. Since 90 percent of known asthmatics have exercise asthma, you can infer that the majority of those with suspected exercise asthma actually have undiagnosed chronic asthma as well.
There are definitely people without asthma as a chronic disease (with hay fever, for instance) who have pure exercise asthma. By and large, though, the majority of people who have exercise asthma have ongoing asthma. But, EIA is often the earliest indicator we have of chronic asthma, because that’s when individuals are going to test their airways most.
So I stress to athletic trainers that when they see exercise asthma, they should suspect that there may be a more serious underlying asthma condition and make sure the athlete gets an evaluation by an allergist or pulmonologist. This is important because asthma is, for the most part, an ongoing disease—particularly in the older patient. In 1991 and 1997, committees convened, via the National Institutes of Health, to make recommendations on the management of asthma. And the bottom line of both committees was that asthma is an inflammatory disease that can scar the airway—that it can be irreversible—which is something we never realized before. And 90 percent of adult asthmatics over 20 years old do not remit. When you look in their airways, they’ve got inflammation and they’ve got scarring.
The key point for athletic trainers, then, is all chronic asthma—mild, moderate, or severe—is persistent and inflammatory, meaning that athletes really should be on medicine regularly if they have ongoing asthma other than exercise asthma.
Are competitive athletes a particularly difficult group to diagnose when it comes to this condition?
We know from our own studies that a large percentage, as many as 20 to 30 percent, of athletes who have EIA are undiagnosed. This is, in part, because denial is a major problem in athletes, particularly in teenagers. And the more high-performance the athletes are, the more likely they will be in denial. They suppress any health concerns, unless they’re overwhelmed by them, because they’re afraid they’ll be discovered and be booted off the team, or they’ll have to take medications they don’t want to take. So athletic trainers have to assume that half of the athletes that they’re dealing with are probably not telling them the whole truth about their health history. Either that or the athletes are suppressing it themselves—not lying about it, but they simply don’t want to know.
Does this put the onus on the athletic trainer, then, to be more observant of their athletes’ behavior?
Absolutely. I think the athletic trainer has a very special responsibility. As an athletic trainer, you have a tremendous amount of power with athletes that no one else has. Clinicians don’t have that kind of power because athletes view them as an impediment. But if the athletic trainer tells them to do something, the athletes are going to listen, because he or she is viewed as the expert in yielding outstanding performance.
So, first, athletic trainers need to be on the lookout for this condition in an athlete. That is, they should arrange preseason physical exams that establish a careful history. But they have to be sleuths as well. They have to recognize that, often, the history alone may not be enough. That’s where evaluation through an exercise challenge comes in. And, finally, it’s also their responsibility to be aware of what medications diagnosed athletes should be, or are being, managed with. Although athletic trainers don’t administer any of these medicines, they can be educators and advocates for their regular use.
How can athletic trainers help prevent the onset of exercise asthma among their athletes?
First, an athletic trainer should be certain that those with prescriptions premedicate with their beta-agonist bronchodilator, like albuterol. A short-acting bronchodilator, for example, taken five to 60 minutes before exercise will keep airways clear for two to three hours. They can also handle exercise asthma by encouraging athletes to breathe through their nose as much as possible, or to breathe through a face mask.
The second way to control EIA is by having athletes warm up at a vigorous rate—one and a half to two times their heart rate—for two to three minutes. Sprints are a good example of this, as well as running in place and calisthenics. This brings on the refractile period. The refractile period goes back to the concept that you’re releasing allergic chemicals. Those chemicals have to be made. If they are released and you continue exercising, the cells can’t make them fast enough again, so you won’t have any further asthma. And that’s where marathoners and other people get second winds. They probably experience some exercise asthma after five to seven minutes, and then they keep running and the allergic cells can’t generate chemicals fast enough to trigger asthma again.
Athletes should also cool down when they’re through. According to the American Association of Asthma, Allergy, and Immunology (AAAAI), a cooldown period prevents air in the lungs from changing rapidly from cold to warm, and thus may prevent EIA symptoms from appearing post-exercise.
An athletic trainer should also know that pure exercise asthma is usually self-limited, so even if you don’t treat it pharmacologically or through warmups and cooldowns, the athlete can exercise through it. That is, if you keep exercising, after an hour you will have depleted all your allergic chemicals and you will no longer feel exercise asthma. But until you’ve depleted all your allergic chemicals, your performance will be affected.
How debilitating can EIA be to performance?
Probably the most powerful example of this is Nancy Hogshead, who wrote a book on this. She failed to win her seventh gold medal because there was a 1/100th second difference between herself and the nearest competitor, and her exercise asthma prevented her from getting there. For you and I, these differences aren’t terribly important, but if you’re an elite competitive athlete, it certainly makes a difference.
But generally, pure exercise asthma alone will impair performance transiently. If you have a competitive athlete, he or she can exercise through it. He or she will get chest pains and discomfort, and it may impair performance for up to an hour or two if they don’t do the warmup, but, eventually, the refractile period will kick in.
From a psychological standpoint, however, there’s a tremendous impact. There’s a loss of morale associated with an athlete’s inability to keep up or meet his or her performance goals. And for teenagers, it’s often a source of embarrassment.
And, certainly, if the exercise asthma indicates underlying asthma, then the physical limitations can be dramatic. Chronic asthma can clearly impair performance—perhaps even lead to the athlete not being able to perform at all.
What can an athletic trainer do to be certain an athlete diagnosed with asthma or EIA is, in fact, taking his or her medication?
I think the most important means of monitoring asthma is to have a peak flow meter, which is very easy to use. Then, athletic trainers can have athletes do a peak flow test before they go on the field. If a person has a peak flow below 60 percent of predicted, he or she is in trouble. That’s much worse than a sedentary individual. The athlete shouldn’t be exercising until he or she is adequately treated.
According to the AAAAI, you can also use the peak flow meter to identify athletes with EIA. Measure airflow after a six to eight minute run or activity that induces respiratory symptoms. Take intermittent measurements for 30 minutes after exercise ends. An airflow decrease of 15 to 20 percent is required for an athlete to be considered positive for EIA.
But if you’re going to use a peak flow meter, you have to recognize the limitations. If you have a high-performance athlete, you have to set up a different curve. That’s the tricky part. An athlete’s peak flow might be 120 percent of predicted, normally. So when we do breathing tests, I always teach my residents to do a pre and post test—that is, you do a baseline breathing test on the athlete, and then give him or her a bronchodilator to see if his or her reading improves. So you have to set up a whole new set of goals. But if you do peak flows regularly with your athlete, you know what his or her baselines are.