What is exercise-induced laryngeal obstruction?
The voice box area, or larynx, in sufferers of exercise-induced laryngeal obstruction or EILO can start to close when they're exercising.
This gives rise to a sensation of not being able to get a breath in/struggling to breathe during exercise and usually causes a wheezy sound or noise, most noticeably when breathing in. The condition is a very common cause of breathing difficulties and one study in Scandinavia found that as many as 1 in 20 athletic individuals might have the condition.
Is exercise-induced laryngeal obstruction serious?
It's serious for an athlete’s performance and thus competition or career progression in that it's often completely overlooked or mis-diagnosed as asthma. Many individuals therefore are told they have ‘asthma’, usually because there's a report of a wheeze and breathlessness, and yet don’t respond to this treatment. It has no long-term implications for health because it usually settles on stopping exercise and most people with EILO only get problems when they exercise.
How does exercise-induced laryngeal obstruction affect you and your training and racing?
Exercise-induced laryngeal obstruction can cause symptoms that might make you feel suddenly breathlessness and many individuals with EILO report having to have dropped out of a race/triathlon because of this problem. Alternatively it can build up in training and thus limit ability to train/undertake brick sessions.
What causes exercise-induced laryngeal obstruction?
There are a number of studies being undertaken to understand what causes EILO. It most probably arises from an imbalance in the structure so that the muscles and nerve fibres that would act to keep the larynx open become overwhelmed by the high level of breathing during sport and thus the structures can start to close in.
One way to help doctors understand your problem is to take a selfie-type video recording when you develop symptoms and to show this to your doctor – with the question, could this be EILO? A great resource for more info is
Who is most likely to developing exercise-induced laryngeal obstruction?
EILO is most commonly seen in adolescents/young adults with a slight female predominance described in most of the research papers. This being said, for many athletes they only start to take up sport later in life (e.g. competitive triathlon) and thus EILO may only become apparent when they're older and have started to undertaken vigorous exercise. It seems to be very common in swimmers and this might be the result of the demands placed on the upper airway during swimming.
How can you treat exercise-induced laryngeal obstruction?
Over the past few years there has been real progress in our understanding of how some highly developed and specialist breathing techniques can help with EILO. In the US, these techniques have proven to cure the condition and can control even severe EILO. We're now using and teaching these techniques in the UK and generally we see great success with breathing technique work and this corrects the problem.
If this fails then occasionally a small surgical procedure can be undertaken and this can make a big difference, but only in certain types of EILO.
Dr James Hull is a respiratory specialist at The Centre for Health & Human Performance (CHHP) www.CHHP.com