Exercise-induced Asthma – the myths

I recently heard someone complaining that an athlete was using an inhaler during competition, insisting that it was cheating as the athlete was gaining an unfair advantage. Now my daughter has been using an inhaler to relieve the symptoms of exercise-induced asthma for more than 20 years, so I have seen first-hand what happens if she doesn’t use her inhaler before training or racing. There are three fallacies about the use of inhalers that I want to address:

  • Inhalers contain a steroid, which is a banned substance, so using an inhaler is performance-enhancing and hence is cheating.
  • Inhalers are now being used by athletes who don’t have asthma to boost their performance.
  • Using an inhaler during a race can give an extra boost.

Let us first look at what is exercise-induced asthma and why in might affect middle and long distance runners, particularly those doing cross country during the winter:

“During normal breathing, the air we take in is first warmed and moistened by the nasal passages. Because people tend to breathe through their mouths when they exercise, they are inhaling colder and drier air.

In exercise-induced asthma, the muscle bands around the airways are sensitive to these changes in temperature and humidity and react by contracting, which narrows the airway. This results in symptoms of exercise-induced asthma, which include:

  • Coughing with asthma
  • Tightening of the chest
  • Wheezing
  • Unusual fatigue while exercising
  • Shortness of breath when exercising

The symptoms of exercise-induced asthma generally begin within 5 to 20 minutes after the start of exercise, or 5 to 10 minutes after brief exercise has stopped.” (https://www.webmd.com/asthma/guide/exercise-induced-asthma#1)

Let’s now look at the first fallacy, that inhalers contain steroids that are performance enhancing. Inhalers, such as Ventolin or salbutamol, which are regularly prescribed to relieve exercise-induced asthma do indeed contain a steroid but not the banned anabolic steroids. “Despite their name, most people with asthma are aware that corticosteroids—that can either be taken as an inhaler, or may be taken as a pill, prednisone, in more severe situations—are not the same as the “steroids” that athletes use for enhancing performance—known as anabolic steroids. Corticosteroids taken by those with asthma simply reduce inflammation in the body, while anabolic steroids have a host of effects that can be performance enhancing.” (https://asthma.net/living/exercise-elite-athletes-anti-doping-and-fair-play/)

So can you fall foul of anti-doping regulations by using an inhaler too many times in a day? The following quotation is taken from a World Anti-Doping Agency guidelines (published on 19 January 2019), where one puff of salbutamol inhaler delivers a dose of approximately 100 micrograms:

“Inhaled salbutamol is not prohibited at maximum doses of 1,600 micrograms over 24 hours; in divided doses not to exceed 800 micrograms over 12 hours. However, the presence of salbutamol in the urine in excess of 1000 ng/mL is presumed not to be a therapeutic use of the substance and will be considered as an adverse analytical finding. The athlete would then need to document the details of his/her medical condition and medication use. The athlete may then be required to prove, by a controlled pharmacokinetic study (see Annex 2) that the abnormal test result was the consequence of the use of a therapeutic dose (maximum 1600 micrograms over 24 hours in divided doses not to exceed 800 micrograms over 12 hours starting from any dose) of inhaled salbutamol.” (https://www.wada-ama.org/sites/default/files/resources/files/tuec_asthma_17012019_en.pdf)

The second fallacy is that inhalers are being used by non-asthmatic athletes to gain advantage. There is a study reported in the British Medical Journal of a trial with 36 healthy non-asthmatic athletes, in which some of the athletes were given salbutamol, while others were given a placebo (a substance that looks the same as the salbutamol but has no effect). The conclusion of the study was “Inhaled salbutamol did not improve peak oxygen uptake in healthy, non-asthmatic, non-athlete individuals compared with placebo.” You can see the article at https://www.ncbi.nlm.nih.gov/pubmed/30233808

You could also look at https://www.outsideonline.com/1783866/will-inhaler-enhance-my-performance

The third fallacy is that asthmatic athletes can get a boost by using an inhaler during exercise. Can using an inhaler while running be effective? Those who have contacts with asthmatics know that the use of an inhaler requires the athlete to inhale the substance and keep it within their bodies for a time so that the substance diffuses into the lungs in order to have an effect. If you are breathing heavily while running, the inhalant would go in and then straight out again before it could have any effect. This observation was confirmed by a local GP. Carrying an inhaler can be essential if the risk of an asthma attack during exercise is increased, but you would only normally use it after stopping the exercise.

Finally, if you want to understand how prevalent exercise-induced asthma is in elite athletes, such as Paula Ratcliffe, you can read a recent article in the Guardian:


Mick Bromilow

Chair, Marshall Milton Keynes