Exercise-Induced Asthma: Signs, Triggers, and Management
EIB is the narrowing of the airways after physical exertion leading to shortness of breath.
This article will explain how EIB occurs, signs to look out for when exercising, treatment, and more.
Many people may experience mild respiratory effects when exercising, which can be benign.
However, EIB is a medical condition that causes airflow obstruction as a result of exercise or physical exertion.
This constriction occurs when certain conditions alter lung function.
Physical exertion can cause you to breathe faster and more deeply because the body requires increased amounts of oxygen during exercise.
When you breathe in deeply, larger amounts of air enter the airways. This air requires additional heating and humidifying, and you may experience additional irritants or triggers.
In people who are susceptible to EIB, this can trigger changes in lung function and bodily response. These changes result in the contraction of the bronchial smooth muscle of the airway.
EIB occurs in 40–90% of people who already experience other asthmatic conditions and around 20% of people who do not experience other asthma at all.
It is unknown why some people experience EIB and others do not.
Specific environmental factors can trigger an EIB episode, in addition to intensive activity. These can include:
- exposure to other irritants — for example, smoke and strong fumes
- a recent cold or asthmatic episode
- air temperature
- dry air
- chlorine in pools
What triggers an episode of EIB can vary according to each person. Knowing your own triggers and reactions will help you adequately treat symptoms or plan to avoid them.
EIB symptoms can begin during exercise, and can continue to become more severe 5–10 minutes after stopping an activity.
Coughing is the most common symptom.
Exercise-induced asthma vs. reduced physical fitness
Exercising while experiencing reduced physical fitness can cause symptoms that are similar to the symptoms of EIB. These similar symptoms can include chest tightness, shortness of breath, and fatigue.
However, EIB is more likely to include a cough or wheezing. Additionally, shortness of breath or fatigue from reduced physical fitness normally resolves quickly and on its own. Respiratory symptoms that do not improve quickly after stopping an activity may indicate asthma or another condition that requires immediate medical attention.
It can be difficult to perceive the difference between symptoms of EIB and reduced physical fitness, so diagnostic tests run by your doctor can help.
As respiratory conditions in severe cases can present a life threatening situation, and untreated conditions can have further complications, contact your doctor after experiencing any persistent or severe respiratory symptoms.
Respiratory conditions can cause a life threatening situation and may require emergency care.
Additionally, as symptoms of EIB can coincide with other conditions that may pose a risk to life, such as anaphylaxis or respiratory failure, it is important to monitor the signs and symptoms of anyone experiencing respiratory effects.
Seek emergency medical care or call 911 for symptoms such as:
EIB symptoms may present the same as symptoms of other conditions affecting the airways. As a result, it is not easy to diagnose EIB based on symptoms alone, and your doctor may need to run tests to diagnose the underlying condition.
In addition to testing, your doctor will likely ask for your medical and symptom history.
Tests for EIB can include:
- Pulmonary function tests: These tests involve measuring your breathing under various conditions, including with a bronchodilator to evaluate lung function.
- Exercise challenge testing: This test is performed in a controlled, dry environment. Periodic measurements of breath, called spirometry, are taken during the challenge. A reduction in airflow after exercise is diagnostic of EIB.
- Fractional excretion of nitric oxide (FENO) testing: FENO testing measures inflammatory responses to help distinguish asthma from other potential causes of the same symptoms.
Treatment will aim to avoid or reduce symptoms and allow you to exercise without limitation.
To achieve this, methods for treating EIB may include both clinical treatments and symptom or self-management techniques.
Clinical treatments for EIB are primarily medication-based.
Medications for EIB that your doctor may prescribe include:
- Short-acting beta agonists (SABA): SABAs are bronchodilators taken before exercise. They relax the muscles lining the airway. They can have few side effects, but some may develop a tolerative effect with long-term use and around 15–20% of people may not respond to SABA treatment.
- Inhaled corticosteroids (ICSs): If a SABA does not improve symptoms, or if you need to use a SABA daily, an ICS can be a further option. ICSs may provide more effective longer-term treatment and can be effective in people with underlying asthma.
- Leukotriene receptor antagonist (LTRA): LTRAs address the inflammatory responses involved with EIB. They can also provide longer-term treatment through bronchodilation without creating tolerance.
- Antihistamines: Your doctor may prescribe an antihistamine for underlying allergies.
Nonclinical management methods can help avoid or improve symptoms of EIB.
These methods can include self-management techniques you can implement yourself.
Avoiding triggers while exercising
Avoid exercising in environments high in allergens or irritants such as pollen, ozone, and exhaust. Also avoid swimming in pools with high levels of chlorine.
Wearing a mask or mechanical barrier may also help avoid irritants, and also improve the warmth and humidity of the air you breathe in. Special masks known as heat or moisture exchanger masks may help to avoid severe symptoms.
To allow you to exercise without limitation, recording your symptoms as they occur may help indicate which activities to avoid. This can help you to know which activities you can do without triggering symptoms of EIB.
Warm-ups before exercise
Warming up before periods of exercise or intensive activity for around 10 minutes may help to manage symptoms.
Additionally, increasing your tolerance and endurance with exercise may help. Decreasing bodyweight for people who experience obesity may provide additional benefits.
Another management technique that may help is to choose sports or exercises that offer a lower risk of triggering EIB. This can include sports that do not have to involve more than 5–8 minutes of sustained intense activity, including:
- martial arts
However, evidence for the beneficial effects of breath-work training is currently limited, and further research may be necessary.
Respiratory muscle training may also help to ensure proper breathing technique and increase respiratory muscle strength.
Here are some frequently asked questions about EIB.
How long does exercise-induced asthma last?
Episodes of EIB generally resolve 20–40 minutes after stopping the exercise.
However, some individuals may experience symptoms 4–12 hours post-exercise, known as a late-phase or second-wave symptoms. These late-phase symptoms can be less severe and may resolve up to 24 hours after exercise.
Can exercise-induced asthma ever go away?
EIB is not yet completely curable. However, proper treatment and management techniques can allow people with EIB to lead a physical life free of many symptoms.
Many people with EIB are still able to continue physical activity, performing at the same level as peers, including competitively and professionally. In fact, many elite athletes experience EIB and are still able to perform. A 2018 evaluation notes that as many as 23% of United States athletes experienced EIB during the 1998 winter Olympics.
What happens if you leave
exercise-induced asthma untreated?
Untreated or poorly managed EIB can lead to a reduction in quality of life due to reduced movement and physical activity.
Other complications of untreated respiratory illness can include:
- lung infections
- disruption to life
- delays in growth or puberty in children
Severe episodes of respiratory obstruction can also be life threatening.
Exercise-induced asthma is commonly known as EIB today.
EIB involves constriction of the airways as a result of physical exertion and further environmental triggers.
Proper treatment and management of EIB can help you to maintain physical activity, up to competitive and professional levels.
However, untreated EIB can limit quality of life and health, and untreated respiratory conditions can have further complications, so contact your doctor as soon as possible for any respiratory symptoms.
Severe respiratory symptoms may require emergency medical care.