Having exercised induced asthma "can be caused by....breathing cold air, dry air, ordinary pre-existing asthma, air pollution and other factors" according to the Mayo Clinic. This discussion has been around in athletic-related magazines and forums for years. I would like to see a test on someone who is not an asthma sufferer, for instance, timed laps with and without the drug. To suggest the medication helps prevent injury is "a bit of a stretch" to put it mildly, If it were true then it would rank alongside penicillin as a wonder-drug and we'd all be on it. As things stand, there is no definitive test for asthma just like the common cold, only "symptons suggesting", unlike steroid and testosterone-level measuring. From personal experience, witnessing someone suffering a severe asthma attack is a mixture of feeling utterly helpless and fear, especially if it's a child.