For all the miles Jack Robb has run over the years, it was only recently that he began to struggle to breathe.
At times, he says, it was so scary, he started to panic.
Everything just starts moving real slow. You feel like somebody has a hand over your mouth and you just can't let loose.
Jack was diagnosed with asthma brought on by his workouts, and his doctor prescribed an inhaler.
But within two weeks, even that wasn't enough.
Jack might not even have exercise-induced asthma, or if he does, it wasn't the complete diagnosis.
And that's much more common than you might think.
Dr. Todd Olin is a lung specialist at National Jewish Health in Denver.
As the leading respiratory hospital in the nation, thousands of asthma patients are referred here for further testing.
But a recent study among those patients found one in four didn't even have asthma, and 70% had other conditions that went undiagnosed.
While it's logical for a general practitioner to treat a breathing problem in a child as asthma, there are other breathing problems out there.
And for the children that are failing therapy, we need to think about those other diagnoses.
Including things that mimic asthma, like allergies, acid reflux, and even heart problems.
During a sophisticated test like this, doctors used a camera to watch Jack's throat during exercise and diagnosed him with vocal cord dysfunction.
It's not asthma and can't be fixed with asthma medicine.
I personally find that speech therapists are the mainstay of therapy.
However, sports psychologists are hugely important.
Dr. Olin says if you have a child with asthma who continues to struggle, even with medicine, you may want to rethink the diagnosis to get them on a more appropriate path to good health.
At National Jewish Health in Denver, this is Clark Powell reporting.