Exercise Induced Asthma vs Out of Shape: Why DO you Wheeze After Running?

by Patrick McKeown

What is exercise-induced asthma?

Exercise-induced asthma is a condition in which breathing symptoms occur during or after exercise. You might experience painful inflammation and swelling in your airways, nasal congestion, wheezing and coughing.

Although you may not have asthma when you don’t exercise, the symptoms look and feel the same. Symptoms may occur as soon as you start exercising, or just after you finish. And sometimes they flare up as many as 12 hours after your workout.

Asthma symptoms triggered by exercise are called exercise-induced asthma or exercise-induced bronchoconstriction (EIB). The word bronchoconstriction means that the bronchi, the passages of the windpipe and lungs, have become constricted, or narrow. This happens when inflammation strikes. The two terms — asthma and bronchoconstriction — are often used interchangeably, though EIB more accurately refers to acute airflow obstruction without asthma symptoms.

Do I have exercise-induced asthma?

Exercise-induced asthma is not choosy. It doesn’t care who you are or how hard you train. A high proportion of top athletes suffer with sport-induced asthma, and it is more common in the higher tiers of professional sports. Even high-profile sporting stars are known to have exercise-induced asthma, and symptoms are more severe in people who train the most. This seems to contradict the advice that regular exercise can improve asthma control [1]. The truth is, intense physical training may leave your immune system more vulnerable. If you train for many hours a week, there is no getting away from the fact your breathing symptoms are likely to affect your performance and your long-term health.

Is exercise induced asthma common?

Yes. Around 90% of asthma sufferers get symptoms during or after physical exercise. And about 10% of people who don’t have asthma experience the symptoms of exercise-induced asthma. Among athletes, 15-25% have symptoms [2].

What does exercise-induced asthma feel like

You may have some (or all) of these symptoms:

• Wheezing after running or working out
• Shortness of breath. You may feel like it’s hard to get enough air because you can’t exhale fully
• Coughing after running or physical exercise
• Tightness or burning in your chest or lungs
• Excessive fatigue/getting tired sooner than normal, needing to stop frequently to catch your breath

How long does exercise induced bronchoconstriction last?

Symptoms will usually begin to fade after around 30 minutes’ rest. If you have late-phase symptoms, which occur up to 12 hours after exercise, it may take you a day to recover.

What causes exercise induced asthma?

A study at the Mater Hospital in Brisbane found that when the breathing volume of adults with asthma decreased from 14 liters to 9.6 liters per minute, their symptoms reduced by 70%. What’s more, the need for rescue medication decreased by 90%, and the need for preventative steroid medication decreased by 50% [3].

The more breathing volume reduced towards normal, the more symptoms including coughing, wheezing, tightness in the chest and breathlessness, simply stopped. Meanwhile, the control group, who were taught the hospital’s in-house asthma-management program, made zero progress!

Since this trial, further research has confirmed that people with asthma who practice reduced breathing exercises have far better asthma control. And that their need for preventative steroid and rescue medication significantly reduces within three to six months [4,5].

2. You breathe through your mouth during exercise, rest, and sleep

The first step in addressing chronic over breathing is to make the switch from mouth to nose breathing. Nasal breathing is important for everyone. But if you’re prone to exercise-induced asthma, it is vital.

Researchers studied the effects of nasal breathing and oral breathing on exercise-induced asthma. Fifteen people were recruited for the study and asked to breathe only through their nose. The study found that:

“The post-exercise bronchoconstrictive response was markedly reduced as compared with the response obtained by oral (mouth) breathing during exercise, indicating a beneficial effect of nasal breathing.” [9]

Whether you have chronic asthma or not, mouth breathing is one of the main triggers for exercise-induced asthma. One reason for this is that breathing through an open mouth leaves you more vulnerable to inhaled allergens. This is a particular issue for cyclists, regardless of fitness. Again, it’s common in riders at Olympic level. This prevalence may be due to long training sessions and high breathing volume. A lot of cycling takes place outdoors — and on roads — where exposure to pollutants is high.

Mouth breathing influences sports-induced asthma in several ways:

• It leaves your airways unprotected from cold, dry air, and airborne viruses, bacteria, allergens, and other particles [10]
• It means you breathe a greater volume of air. This causes you to expel too much carbon dioxide from your lungs. Carbon dioxide is a natural “opener” of the smooth muscle in the airways. The loss of carbon dioxide contributes to airway constriction
• Unlike nose breathing, mouth breathing does not give you the benefit of nasal nitric oxide, which supports immune defense [11,12,13].

In a paper published in the American Review of Respiratory Disease, researchers studied the beneficial effects of nasal breathing on exercise-induced asthma. The study observed that most subjects with asthma spontaneously breathed with their mouths open when instructed to breathe “naturally.” The authors found that mouth breathing during exercise caused the airways to narrow even further. In contrast, when subjects were asked to breathe only through their nose during exercise, exercise-induced asthma did not occur at all [14].

In other words, by breathing through your nose during exercise, you can reduce exercise-induced asthma, or avoid it altogether [9].

3. You’ve been given bad breathing advice

Many sports coaches teach the practice of breathing in through the nose and out through the mouth. This is bad advice. Scientists have studied this type of breathing. They found that it causes 200% more nasal congestion that lasts for at least ten minutes. A blocked nose means you default to mouth breathing, and mouth breathing will exacerbate your asthma. Exhaling through your mouth will also contribute to dehydration, and this can trigger airway irritation.

4. You’re breathing cold, dry air straight into your lungs

Whether you exercise in the great outdoors or in the gym, it’s likely you will encounter air that is cold and dry at least some of the time. When you breathe through your nose, air arrives in your airways warmed and moistened. If you breathe hard through an open mouth, you take in cold, dry air. This dehydrates and irritates the airway and can cause asthma symptoms or exercise-induced bronchoconstriction.

Cold air will do more damage when you breathe a large volume of air. As airflow increases, so too does the cooling effect of inhaled air. A recent study from researchers in Italy makes a direct connection between over-breathing and cold-induced airway damage [15]. Subjects breathed air at around 20°C at 15 liters and 100 liters per minute. At 15 liters per minute, the temperature in the trachea (windpipe) dropped to 34°C. At 100 liters it dropped to 31°C.

With all this in mind, it may be no surprise that exercise-induced asthma is common in people who take part in winter sports. And studies have found a high percentage of skiers suffer with allergic rhinitis [16]. People with rhinitis often exhibit bronchial hyperresponsiveness, which is a risk factor for asthma.

5. You spend too much time in a chlorinated atmosphere

Swimming generally causes much less exercise-induced asthma than running or cycling. For this reason, many people with asthma favor swimming when it comes to exercise. The air in an indoor swimming pool is humid and warm. The pressure of water on the chest helps with exhalation. And controlled breathing causes a buildup of carbon dioxide, which relaxes the airways.

These differences in breathing pattern and volume between land-based exercise and swimming are significant for people with asthma [17]. It is much easier to over-breathe on dry land, as breathing is not restricted in the same way it is in the water. When you swim, breathing volume naturally reduces towards normal. This can provide a much safer and more enjoyable exercise experience for people with asthma [17].

In the words of respiratory consultant, Dr. Peter Donnelly, writing in the medical journal, The Lancet:

“In most land-based forms of exercise, patterns of breathing are not constrained, ventilation increases proportionately throughout exercise and end tidal CO₂ tensions are either normal or low. Therefore, there is no hypercapnic (increased carbon dioxide) stimulus for bronchodilation (airway opening) and asthmatics have no protection.”

One study shows that narrowing of the airways affected 55% of football athletes and 50% of basketball players, but 0% of water polo athletes [18]. What possible explanation could there be for such a glaring disparity? The answer is simple. Water polo training involves breath holding and swimming underwater. This results in higher tolerance to carbon dioxide, increased concentration of nasal nitric oxide, and a reduced breathing volume.

As we have learned already, when breathing volume is normalized, asthma symptoms don’t occur. However, too much time spent in chlorinated pools can damage the lung tissue. This is a particular problem for people with asthma [19,20,21,22] and should be considered when planning your exercise. It is also important to address poor breathing habits outside the pool. Many swimmers practice controlled breathing in the water, but have dysfunctional everyday breathing patterns as soon as they towel off.

How to treat exercise-induced asthma without medication

You may already be aware of natural remedies that focus on diet, weight-reduction, and physical fitness. You may also be careful to avoid triggers. If your trigger is exercise, however, and you want to stay fit and well, this presents a catch-22 situation.

Since asthma is a condition that affects breathing, it makes sense to look to breathing to resolve it. Asthma often exists alongside dysfunctional breathing patterns. As we’ve seen, it can flare up when you over-breathe or breathe through an open mouth. Clinical trials have shown that breathing exercises can help reduce and prevent asthma symptoms. They can even be used to stop an asthma attack.

Here’s what to do to rid yourself of symptoms:

• Restore full time nasal breathing. This means you will learn to breathe through your nose during exercise, rest and sleep.
• If your asthma symptoms are worse when you’re running or working out, train yourself to keep your mouth shut. If you’re wondering how to run with exercise-induced asthma, the answer is this: do all your warm-ups and even all your exercise using only nose breathing. If you feel like the air hunger is too strong, slow down until your breathing feels comfortable. You will soon build back up to your previous pace, and even faster.
• During your exercise warm-up, practice 5 moderate breath holds after exhalation. This helps open the airways, nose, and lungs. It increases CO₂ in the blood, improving body oxygenation. Your muscles get more oxygen, and you get a better workout experience.
• Practice breathing exercises to reduce your breathing volume. When breathing volume is normal, your airways are less vulnerable to trauma, irritation, infection, and swelling.
• Increase your BOLT score to more than 25 seconds. This addresses your everyday tendency for breathlessness. When your BOLT score is low, you will feel breathless during rest. Your airway is more likely to be congested and inflamed. For every 5 second increase in your BOLT score, you will notice a reduction in symptoms of exercise-induced asthma.
• If you regularly wake with a dry mouth in the morning, or snore loudly, try taping your mouth to sleep. This is the only way to reliably prevent nocturnal mouth breathing. You can use a medical paper tape or Patrick’s patented mouth tape for sleep, MYOTAPE.

When should I see my healthcare provider about exercise-induced asthma?

If you or your child are experiencing asthma symptoms triggered by exercise, it’s important to speak to your doctor. There are several conditions with similar symptoms, so do get checked out.

If you have severe difficulty breathing, seek immediate medical help, or take your asthma medication. You should never stop taking prescribed asthma medication without first consulting your medical doctor.

If you have shortness of breath with no airway symptoms, it is worth asking your doctor to check your iron levels.

Can exercise-induced asthma go away?

Final suggestions…

If you have exercise-induced asthma, you may also have nasal congestion. The good news is, you can unblock your nose by practicing a simple breath-holding exercise.

OA BREATHWORK CERTIFICATION

References:

1. Jaakkola, Jouni JK, et al. “Regular exercise improves asthma control in adults: A randomized controlled trial.” Scientific reports1 (2019): 1-11.

2. Miller, Michael G., et al. “National Athletic Trainers’ Association position statement: management of asthma in athletes.” Journal of athletic training3 (2005): 224.

3. Bowler, Simon D., Amanda Green, and Charles A. Mitchell. “Buteyko breathing techniques in asthma: a blinded randomised controlled trial.” Medical journal of Australia11-12 (1998): 575-578.

4. McHugh, Patrick, et al. “Buteyko Breathing Technique for asthma: an effective intervention.” Journal of the new zealand medical association1187 (2003).

5. Cowie, Robert L., et al. “A randomised controlled trial of the Buteyko technique as an adjunct to conventional management of asthma.” Respiratory medicine5 (2008): 726-732.

6. Hallani, M., J. R. Wheatley, and T. C. Amis. “Initiating oral breathing in response to nasal loading: asthmatics versus healthy subjects.” European Respiratory Journal4 (2008): 800-806.

7. Kairaitis, Kristina, et al. “Route of breathing in patients with asthma.” Chest6 (1999): 1646-1652.

8. Hallani, Mervat, John R. Wheatley, and Terence C. Amis. “Enforced mouth breathing decreases lung function in mild asthmatics.” Respirology4 (2008): 553-558.

9. Mangla, P. K., and M. P. S. Menon. “Effect of Nasal and Oral Breathing on exercise‐induced Asthma.” Clinical & Experimental Allergy5 (1981): 433-439.

10. Fried, Robert. The hyperventilation syndrome: Research and clinical treatment. Johns Hopkins University Press, 1987.

11. Djupesland, Per G., et al. “Nitric oxide in the nasal airway: a new dimension in otorhinolaryngology.” American journal of otolaryngology1 (2001): 19-32.

12. Scadding, Glenis. “Nitric oxide in the airways.” Current opinion in otolaryngology & head and neck surgery4 (2007): 258-263.

13. Vural, Çetin, and Anıl Güngör. “Nitric oxide and the upper airways: recent discoveries.” Kulak burun bogaz ihtisas dergisi: KBB= Journal of ear, nose, and throat1 (2003): 39-44.

14. Shturman-Ellstein, R., et al. “The beneficial effect of nasal breathing on exercise-induced bronchoconstriction.” American Review of Respiratory Disease1 (1978): 65-73.

15. D’Amato, Maria, et al. “The impact of cold on the respiratory tract and its consequences to respiratory health.” Clinical and translational allergy1 (2018): 1-8.

16. Surda, Pavol, et al. “Prevalence of rhinitis in athletes: systematic review.” International journal of otolaryngology2017 (2017).

17. Donnelly, PeterM. “Exercise induced asthma: the protective role of CO2 during swimming.” The Lancet8734 (1991): 179-180.

18. Sidiropoulou, Maria P., et al. “Incidence of exercise-induced asthma in adolescent athletes under different training and environmental conditions.” The Journal of Strength & Conditioning Research6 (2012): 1644-1650.

19. Uyan, Z. S., et al. “Swimming pool, respiratory health, and childhood asthma: should we change our beliefs?.” Pediatric pulmonology1 (2009): 31-37.

20. Fjellbirkeland, L., A. Gulsvik, and A. Walløe. “Swimming-induced asthma.” Tidsskrift for den Norske laegeforening: tidsskrift for praktisk medicin, ny raekke17 (1995): 2051-2053.

21. Bernard, Alfred, et al. “Lung hyperpermeability and asthma prevalence in schoolchildren: unexpected associations with the attendance at indoor chlorinated swimming pools.” Occupational and environmental medicine6 (2003): 385-394.

22. Nickmilder, Marc, and Alfred Bernard. “Ecological association between childhood asthma and availability of indoor chlorinated swimming pools in Europe.” Occupational and environmental medicine1 (2007): 37-46.