Many athletes with asthma may be using the wrong treatment

The article will feature on the BMJ's new Olympics portal, an online resource to keep doctors up to date with sports medicine content from across the BMJ Group. The portal will be open until the end of the Olympic and Para-Olympic games at www.bmj.com/olympics.

Asthma is strikingly common in elite athletes and has gradually risen at almost every Olympics since the 1970s. In 2004 almost 21% of Team GB had asthma compared with 8% of the British population.

Marathon runner Paula Radcliffe is a well known athlete with asthma and it is thought that intense exertion over long periods can trigger symptoms.

A belief that inhaled asthma drugs (known as beta-2-agonists or IBAs) could enhance performance led to suspicions that some athletes might be declaring themselves asthmatic in order to take the drugs. But studies have found no evidence that inhaled asthma drugs improve performance. Tests introduced in 2001 revealed that some athletes had been misdiagnosed while others had asthma without realising it.

This has led to concerns that some athletes may be harming themselves by using the wrong medication. For example, many athletes may have exercise-induced asthma which needs to be managed and treated differently to full blown asthma.

However, a 2011 study showed that asthmatic athletes have consistently outperformed healthy athletes at every Olympic Games since 2000. So how do they manage to perform so well, despite their obvious handicap?

Most elite athletes with asthma have a detailed understanding of their condition and how best to control it while still training hard. Paula Radcliffe often talks about her asthma to encourage others to manage their asthma better.

And scientists now agree that exercise in most people with asthma enhances their lung function and improves their quality of life.

"The general message is that mild exercise should be recommended to asthmatics as part of their symptom management programme," says Dr Greg Whyte, former director of research for the British Olympic Association and professor of applied sport and exercise science at Liverpool John Moores University.