Exercise-Induced Laryngeal Obstruction

Exercise-induced laryngeal obstruction (EILO) is a transient, inappropriate narrowing of the larynx during high-intensity exercise that makes it hard to get air in.

It is a common cause of exertional breathlessness in adolescents, young adults and athletes, and is frequently mistaken for asthma or exercise-induced bronchoconstriction (EIB) and treated with inhalers that do not help. Older names include vocal cord dysfunction and paradoxical vocal fold motion. EILO is the current agreed term, and it is the exercise form of inducible laryngeal obstruction.

An athlete labelled with difficult asthma will not improve on escalating inhaled treatment, whereas the right breathing technique often helps. The skill is recognising the pattern and arranging continuous laryngoscopy during exercise (CLE), the test that confirms it.