Speaker's Highlight

• Don Sin University of British Columbia, St. Paul Hospital (Canada)
  Kenneth R. Chapman Toronto General Hospital Research Institute (Canada)
• Parameswaran Nair McMaster University (Canada)
  Carolyn Calfee UCSF (U.S.A.)
• Gregory P. Downey University of Colorado School of Medicine (U.S.A.)
  David A. Schwartz University of Colorado School of Medicine (U.S.A.)
• Neil Schluger Tuberculosis Control Branch, California Department of Public Health (U.S.A.)
  Nick Kim Critical Care & Sleep Medicine, University of California San Diego (U.S.A.)
• Nicola Hananiah Baylor College of Medicine (U.S.A.)
  Jae-Joon Yim Seoul National University College of Medicine (Republic of Korea)
• Koichiro Asano Tokai University School of Medicine (Japan)
  Diahn-Warng Perng Taipei Veterans General Hospital (Taiwan)
• Konstantinos Kostikas University of Ioannina (Greece)
  Karin Klooster University Medical Center Groningen (Kingdom of the Netherlands)

• Exercise-Induced Laryngeal Obstruction in Young Athletes

  For a teenager gasping at the finish line of a Saturday arvo cross-country run, the immediate assumption is often asthma. Many clinicians in Australia default to inhaled bronchodilators, only to find the wheeze does not budge and the athlete keeps pulling up short of breath. Exercise-induced laryngeal obstruction, shortened to EILO, is a frequently missed cause of exertional breathlessness that mimics asthma but originates higher in the airway, at the level of the larynx.

  In practical terms, EILO describes a transient narrowing of the vocal cords and supraglottic structures during heavy exercise. The collapse is mechanical and effort-dependent, which is why it tends to appear in the final minutes of a hard session or during a sprint finish. Lung function at rest is usually preserved, and standard spirometry often looks unremarkable.

  The condition surfaces most often in adolescents and young adults who train hard, whether they are scholarship holders at the Australian Institute of Sport in Canberra, weekend netballers in Brisbane, or junior surf lifesavers on the Coffs Harbour coast. Because symptoms overlap with reactive airway disease, EILO is regularly mislabelled, sometimes for years, and many patients accumulate asthma medications that never quite resolve the problem.

  This overview walks through what EILO looks like, how it differs from exercise-induced asthma, where young athletes can access assessment, and what current management looks like in everyday practice across Australian clinics and sporting settings.

  What EILO Is and Why It Happens

  The larynx sits at the top of the trachea and normally opens wide during vigorous breathing. In EILO, the supraglottic tissues or vocal folds themselves collapse inward at peak ventilation, producing a characteristic stridor rather than the musical wheeze of lower airway narrowing. Adolescents seem particularly vulnerable because their laryngeal cartilage is still maturing and their breathing strategy during effort can default to upper-chest patterns that encourage glottic narrowing.

  Triggers vary between individuals but commonly include sustained high-intensity work, cold dry air such as the brisk mornings over Hobart's Domain, and upper respiratory tract irritation. Co-existing nasal congestion, reflux, or allergic rhinitis can all add to the trigger load, which is why a careful history often uncovers more than one contributing factor in any given patient.

  Who It Affects in Australia

  EILO shows up across the full spectrum of Australian sport. Junior rugby league players in western Sydney, country cricket fast bowlers in regional Victoria, and elite swimmers at state academies all present with similar stories of breathlessness that does not behave like asthma. In junior development pathways, missed diagnosis can be particularly costly because confidence and selection opportunities both suffer when an athlete repeatedly struggles to complete high-intensity efforts.

  Locally, awareness is growing. Sports physicians attached to AFL academies and Swimming Australia programmes have started screening for stridor during field testing, and paediatric respiratory clinics at the Royal Children's Hospital in Melbourne now run dedicated exercise-challenge services. Access gaps remain across regional Australia, where laryngoscopy during exercise is hard to arrange and families often need to travel long distances.

  Distinguishing EILO From Asthma

  EILO and asthma can travel together in the same patient, which makes clinical pattern recognition essential. Asthma tends to cause expiratory wheeze, chest tightness, and cough that may linger after stopping. EILO more often produces inspiratory stridor, a high-pitched noise when breathing in, together with throat tightness, voice change, and a sensation of something stuck in the neck.

  Timing is another practical clue. EILO symptoms peak during maximal effort and ease within minutes of slowing down, whereas asthma symptoms can persist into the cool-down. Athletes frequently describe being able to push through an EILO episode once intensity drops, which is rarely true for bronchoconstriction. When breathing problems persist despite optimised inhaled therapy, looking higher in the airway is the sensible next step. A useful summary of the asthma side of this differential is found in bronchoconstriction in elite athletes, a resource produced alongside this congress material.

  Feature	EILO	Exercise-Induced Asthma
  Main sound	Inspiratory stridor	Expiratory wheeze
  Location of issue	Larynx / supraglottis	Lower airways / bronchi
  Response to reliever puffer	Poor or none	Usually good
  Peak timing	During maximal effort	During or after exercise
  Resting spirometry	Usually normal	May show obstruction
  Diagnostic test	Continuous laryngoscopy during exercise	Bronchial provocation challenge
  First-line treatment	Breathing retraining, speech pathology	Inhaled corticosteroids, beta-agonists

  Diagnostic Pathway and Testing Access

  Referral usually begins with a GP or sports physician, particularly those working with state academies or Auskick development programmes. Continuous laryngoscopy during exercise, known as CLE testing, remains the gold standard and is offered at a handful of tertiary centres including the Royal Children's Hospital Melbourne, the Queensland Children's Hospital in Brisbane, and Sydney's Westmead.

  Waiting lists in the public system can stretch out, and out-of-pocket costs in private clinics vary widely. Families in regional Queensland, the Northern Territory, or far-western New South Wales often travel to a capital city and arrange accommodation for the testing day. Medicare rebates apply to the specialist consultation and most diagnostic work-up, though the exercise provocation component may attract a gap fee. Asthma Australia can help families find clinicians with a specific interest in exercise-related breathing disorders, particularly in states without a dedicated EILO clinic.

  Treatment and Returning to Sport

  Management centres on respiratory retraining delivered by a speech pathologist with experience in upper-airway disorders. Athletes learn to coordinate diaphragmatic breathing with nasal warm-up during effort, to relax the laryngeal posture at high intensity, and to recognise early warning signs so they can downshift before full collapse. Most programmes run over six to eight sessions, with home practice between reviews.

  Surgical options, including supraglottoplasty, are reserved for the small minority with persistent structural collapse that fails conservative care and are rarely needed in adolescents. Pharmacotherapy has a limited standalone role in pure EILO, although treating co-existing rhinitis or reflux can lower the trigger load and is often addressed in parallel.

  The return-to-play plan should be collaborative rather than a clinical decree dropped on a confused teenager. Coaches at school and club level benefit from a plain-language explanation that the athlete is not faking it and that recovery involves graded exposure to hard work. Swimming Australia academies and several AFL club medical teams have begun embedding breathing coaches into rehabilitation pathways, a model worth adapting in community sport where most young athletes actually train.

  For clinicians, the practical takeaway is straightforward. When an Australian adolescent presents with exertional breathlessness that does not respond as expected to standard asthma therapy, particularly when the dominant sound is inspiratory rather than expiratory, think larynx. Referring for continuous laryngoscopy during exercise, engaging a speech pathologist early, and supporting a graded return to training can shorten a frustrating diagnostic journey that otherwise stretches across years and sports seasons.

  Richard Russell Nuffield Department of Clinical Medicine, University of Oxford (United Kingdom)
• Mona Bafadhel King’s College London (United Kingdom)
  David Jackson Guy’s and St Thomas’ Hospital, King’s College London (United Kingdom)
• James Chalmers University of Dundee (United Kingdom)
  David Price University of Aberdeen (United Kingdom)