Exercise induced asthma

Exercise-induced asthma, also known as exercise-induced bronchoconstriction (EIB), is a condition in which vigorous physical activity triggers acute airway narrowing in individuals. This condition is prevalent among both athletes and the general population, affecting approximately 90% of people with asthma and 10% of the population without asthma. Symptoms typically manifest within a few minutes after starting exercise and can peak around 10 to 15 minutes into physical activity.

Symptoms

The primary symptoms of exercise-induced asthma include:

• Coughing
• Wheezing
• Shortness of breath
• Chest tightness or pain
• Decreased exercise endurance

These symptoms often resolve within 30 to 60 minutes of ceasing exercise. However, some individuals may experience a "second wave" of symptoms 4 to 12 hours after exercising, which tends to be less severe and can resolve on its own.

Causes

The exact cause of exercise-induced asthma is not fully understood, but it is believed to be related to the cooling and drying of the airways that occurs during vigorous breathing. Exercise increases the air flow in and out of the lungs, leading to cooling and dehydration of the bronchial tubes' lining, which in turn triggers them to constrict, causing asthma symptoms.

Diagnosis

Diagnosis of exercise-induced asthma involves a thorough medical history and may include:

• A physical examination
• Lung function tests (Spirometry)
• Exercise challenge tests
• Eucapnic voluntary hyperventilation tests
• Mannitol challenge test

Treatment

Management and treatment of exercise-induced asthma may include:

• Pre-exercise use of inhaled beta2-adrenergic agonists
• Incorporation of a proper warm-up and cool-down in exercise routines
• Use of Inhaled corticosteroids for long-term control in individuals with underlying asthma
• Avoidance of known triggers, such as cold air or allergens
• Wearing a mask or scarf over the mouth and nose when exercising in cold weather

Prevention

Preventive strategies are crucial for individuals with exercise-induced asthma. These may include:

• Tailoring exercise routines to include activities less likely to trigger symptoms, such as swimming in a warm, humid environment
• Gradually increasing the intensity of workouts
• Ensuring adequate control of underlying asthma with medication

See also

• Asthma
• Bronchoconstriction
• Pulmonary function test