Introduction
Exercise-induced laryngeal obstruction (EILO) is a caused by an inappropriate narrowing or closesure of the upper airway at the level of the vocal cords (glottis) and/or supraglottis (above the vocal cords) during exercise. This narrowing reduces the amount of air that can get into the lungs, making it harder to breathe and perform physical activity.
Etiology
The larynx adapts to increased airflow during exercise by opening like a valve. Malfunction of this mechanism may cause breathing problems due to reduced opening or closure of the larynx
Symptoms
Symptoms typically appear at maximal effort and recover quickly when exercise/activity ends.
Symptoms can include:
Examination
Laryngoscopy should be performed continuously during exercise in order to observe how the larynx adapts to the requirements for increased airflow during exercise. This test is called a “continuous laryngoscopy during exercise” (CLE) – test
Treatment
Treatment for EILO aims to restore laryngeal patency by activating the posterior cricoarytenoid muscle, the main (and only) laryngeal abductor, which can be done using speech pathology.
There is relatively limited data on the efficacy of treatment strategies, with literature comprised of single-centre studies and small experimental studies. There are no comparative data and there is limited follow up data. Most studies have examined young athletes (typically in the paediatric age range), and generalizability to other populations is unclear.
Behavioural therapies
The modern mainstay of EILO therapies is behavioral therapies, which aim to increase laryngeal control and enable physical activity (generally athletic exercise). These centre on respiratory retraining techniques (breathing advice, laryngeal control therapy), but also involve a holistic approach to an individual’s condition including attention to laryngeal hygiene.
Techniques involve speech pathologists or physiotherapists depending on geographical availability. Protocols have been published (speech language therapists – Karlsen et al,. 2024 and Johnston et al., 2018). These protocols have been applied to individuals with both supraglottic and/or glottic closure.
Biofeedback
The Association for Applied Psychophysiology and Biofeedback (AAPB) defines biofeedback as a process that enables an individual to learn how to change physiological activity for the purposes of improving health and performance.
In the context of EILO, when laryngeal narrowing is actively visualised during endoscopy usually during CLE [cross link to CLE section], a natural opportunity arises for biofeedback. Rescue breathing techniques can be implemented and the session can serve to ensure that an individual learns that a) their symptoms are attributable to laryngeal narrowing, and b) that rescue techniques can provide both objective laryngeal opening and symptomatic improvement (Olin et al, 2017.). In clinical practice, biofeedback is often followed by behavioral therapies.
Inspiratory Muscle Training
Resistive inspiratory muscle training has been trialled in a small number of athletes with findings that individuals who manifested glottic closure had better benefit (Sandnes et al., 2019). The optimal protocol remains uncertain.
Surgery
Surgery is an option for individuals who have moderate to severe supraglottic obstruction and little to no benefit observed from conservative treatments