What Is Exercise-Induced Asthma (EIA)?

Exercise-induced asthma (EIA) is asthma triggered by physical activity. Muscles around your airways narrow or spasm, causing symptoms like coughing, wheezing, and dyspnea (shortness of breath). It's also known as exercise-induced bronchoconstriction (EIB) or sports-induced asthma.

Asthma is a chronic lung disease that causes the airways to become inflamed and narrowed, making breathing difficult. Exercise-induced asthma is fairly common. About 40-90% of people with asthma have EIB, but it also affects about 20% of people without asthma. It can affect people of all ages and fitness levels, including elite athletes.

There's no cure for EIB, and it can be dangerous if ignored. It can also significantly impact your quality of life. Fortunately, it's very treatable.

Exercise-Induced Asthma Symptoms

Symptoms of exercise-induced bronchoconstriction can occur during or after your workout. At first glance, these symptoms may seem similar to how your body naturally responds to exercise. It's not uncommon to feel somewhat out of breath from exercise. Your breathing rate and circulation increase because your body requires more oxygen.

However, there are some key differences between feeling "out of breath" and "short of breath." It's important to recognize signs of EIB so you can follow treatment recommendations and possibly prevent an asthma attack.

EIB symptoms range from mild or severe and might include:

• Dyspnea: This is more than being a little breathless from your workout. Instead, it can feel like you're breathing out of a straw, and the sensation may last after you stop exercising.
• Coughing: A small cough here and there is likely nothing to worry about, but a lot of coughing during or after your workout can be a sign of EIB.
• Chest tightness or pain: This is a squeezing sensation in your chest, ribs, and possibly back that may continue after you stop your workout. It's more intense than typical exercise-induced chest tightness.
• Wheezing: This is a high-pitched whistling or rumbling noise as you breathe. It's often the first symptom of EIB in children.

Exercise-induced bronchoconstriction symptoms often follow a general timeline:

• Begin within three minutes of exercise
• Peak after 10-15 minutes
• Resolve within 30-90 minutes
• A possible refractory period, meaning that symptoms disappear for a few hours afterward
  

Some people don't have symptoms, which can lead to a delay in diagnosis.

What Causes Exercise-Induced Asthma?

Cold, dry air seems to be the main trigger for exercise-induced bronchoconstriction. Other triggers include:

• Low air quality
• Irritants like smoke and fumes
• A recent asthma attack or respiratory infection

People with chronic asthma or who have allergies are most at risk for EIB. It might be a sign of poorly controlled asthma. Exercise can also increase mouth breathing, which increases exposure to possible irritants.

Risk Factors

Risk factors for exercise-induced bronchoconstriction include:

• Personal or family history of asthma
• History of atopy (a tendency to have strong immune reactions to allergens)
• History of allergic rhinitis, or "hay fever" (allergies that cause symptoms like sneezing, watery eyes, and congestion)
• Smoking or cigarette smoke exposure
• Living or exercising in a high-pollution area

Which Sports Are Best for EIB?

You will likely be able to participate in all types of exercise if you have exercise-induced bronchoconstriction, but you might need to take medication (e.g., use your inhaler) first and use other precautions.

EIB triggers include:

• Cold, dry air
• Activities that require ongoing exercise for longer periods of time (e.g., more than eight minutes)
• Higher exercise intensity

There are some other potential factors as well. Sports and activities that more commonly cause asthma symptoms include:

• Swimming: Chlorination in indoor spaces might trigger asthma and EIB.
• Ice-skating and ice hockey: The cold and dry air, as well as chemicals in ice-resurfacing machines, can trigger EIB.
• Cold-weather outdoor sports: This includes running, cross-country skiing, and soccer.
• Hot yoga: Exercising in extremely high temperatures can trigger EIB.

Moderate-risk activities include:

• Soccer
• Rugby
• Basketball
• Volleyball
• Baseball
  

Lower-risk activities that involve shorter exercise bursts include:

• Walking
• Tennis
• Gymnastics
• Weightlifting
• Sprinting
  

How Is Exercise-Induced Asthma Diagnosed?

Diagnosing exercise-induced asthma requires ruling out other possible conditions as well as testing for asthma.

Other Conditions That Can Cause Dyspnea

Many conditions can cause dyspnea during exercise, with congestive heart failure being the most common cause.

Respiratory conditions include:

• Chronic obstructive pulmonary disease (COPD): A group of chronic, progressive lung diseases that limit airflow to the lungs and cause difficulty breathing
• Pneumonia: A common lung infection caused by bacterial, viral, and fungal infections
• Aspiration: When food, liquid, or another substance moves through an airway into the lungs

Cardiovascular causes include:

• Acute coronary syndrome: A group of conditions that cause sudden, restricted blood flow to the heart
• Pulmonary edema: Swelling due to fluid accumulation in the lungs, which can make breathing more difficult
• Arrhythmia: An irregular heartbeat caused by an abnormal heart rate or heart rhythm

Other causes include:

• Anemia: A condition that occurs when your blood has a reduced number of red blood cells or hemoglobin (protein that helps your red blood cells transport oxygen from your lungs to the rest of your body)
• Metabolic acidosis: Acid buildup due to kidney disease or failure
• Cirrhosis: A condition that causes extreme scarring and damage to the liver

This is not an exhaustive list. Many other conditions can cause dyspnea.

Diagnosing EIB

The EIB diagnosis process varies from person to person. It might include:

• Personal medical history: Many conditions can cause dyspnea, and people with asthma are more likely to have EIB.
• Details about exercise habits: This might include types of exercise, length of exercise time, how often you exercise, and where you exercise.
• Family medical history: Asthma runs in families.
• Pulmonary function testing: You blow into a tube hooked up to a computer that measures how well your lungs work and if there is inflammation in your airways. The results can determine whether you have asthma.
• Exercise challenge testing: You run on a treadmill or use an exercise bike. The provider monitors your lung functioning during and afterward. Certain breathing patterns might indicate a condition like EIB.
• Allergy testing: Allergy-induced asthma can cause symptoms like coughing during exercise.

Blood samples and medical imaging tests can help rule out other potential dyspnea causes, such as respiratory conditions, cardiovascular conditions, and anemia.

How Do You Treat Exercise-Induced Asthma?

Exercise-induced asthma isn't reversible, but you can manage symptoms effectively. You might work with multiple specialists, such as your primary care doctor, an allergist, or an immunologist (a doctor who specializes in conditions related to the immune system).

Medication

Medication is the first-line treatment, and it might be used to treat or prevent symptoms. Medications might include those commonly used to treat asthma, such as:

• Short-acting beta agonists (SABA): The most common treatment for EIB is inhaling a fast-acting asthma medicine (bronchodilator) like albuterol before you exercise. Albuterol works by relaxing the muscles around the airways. Most people take it about 15 minutes before a workout. It lasts about 2-4 hours.
• Inhaled corticosteroids (ICS): These are usually used if SABA isn't effective or needs to be used daily. Examples include Breyna and Symbicort (budesonide-formoterol) and Dulera (mometasone-formoterol), which are also long-acting bronchodilators. These medications work quickly and last up to 12 hours.
• Leukotriene modifiers: These long-term anti-inflammatory oral (pill) medications decrease airway narrowing and mucus production, helping to prevent EIB. Examples include Singulair (montelukast) and Accolate (zafirlukast). Leukotriene modifiers do not relieve EIB symptoms.

You may take a combination of medications, such as a long-acting asthma medicine and a steroid.

Mild attacks generally require two puffs of a SABA like albuterol or one puff of an inhaled corticosteroid. You would likely repeat this every few hours as needed for symptoms. A more severe attack might require more puffs of rescue medication or a nebulizer machine (a device that turns liquid medication into a mist that you inhale).

Other Treatment Options

Other strategies might help improve symptoms of EIB, including the following:

• Increasing your exercise tolerance by engaging in regular exercise
• Consuming caffeine before exercise.
• Eating a low-salt diet
  

Prevention

EIB is a very manageable condition and when treated correctly, it shouldn't impede your ability to work out.

Here are some recommendations for preventing EIB episodes:

• Start exercise with a warm-up and end with a cool-down
• Limit strenuous outdoor activity if the air quality is low
• Avoid exercising in cold weather or cover your nose and mouth
• Stop exercising if you notice symptoms like coughing, shortness of breath, or chest tightness
• Try belly breathing exercises
• Always have your rescue inhaler to use as needed
  

A Quick Review

Exercise-induced bronchoconstriction, or EIB—also known as exercise-induced asthma—is a relatively common condition that can cause uncomfortable and sometimes dangerous symptoms before or after exercise.

Fortunately, EIB is very treatable and does not usually impact your ability to engage in physical activity. Reach out to your healthcare provider if you have symptoms of exercise-induced asthma. Medication can help resolve or prevent symptoms, as can certain exercise precautions.