More than a third of college athletes checked for breathing problems had exercise-induced asthma, according to an alarming new study. The study included athletes who had no previous history of asthma.

The findings match up with earlier research that found that exercise-induced asthma was surprisingly common among Olympic athletes.

The results suggest there are a significant number of athletes who suffer from undiagnosed exercise-induced asthma.

Researchers screened 107 Ohio State varsity athletes for exercise−induced asthma. Forty−two (39 percent) of the athletes tested positive, and 36 of those 42 athletes had no prior history of asthma.

The results suggest there are a significant number of athletes who suffer from undiagnosed exercise−induced asthma.

Exercise−induced asthma occurs when airflow to the lungs is reduced by the narrowing and closing of the airways. This airway obstruction usually occurs just after exercise.

"We targeted varsity athletes in this study because many of the reported severe episodes of asthma provoked by exercise have occurred among competitive athletes under the age of 21," said Dr. Jonathan Parsons, a lung specialist, associate director of the at Ohio State University Medical Center's Asthma Center and lead author of the study. "Now that we've demonstrated how common this problem can be, more research is needed to determine the best way to monitor and manage athletes at the highest risk of developing symptoms while participating in their sports."

"One important finding of this study is that a history of symptoms with exercise is not enough to make a correct diagnosis," said Parsons. "Diagnosis and treatment of exercise−induced asthma based solely upon subjective symptoms could increase the number of inaccurate diagnoses and expose people to unnecessary medications."

"Objective confirmation of suspected exercise−induced asthma with appropriate testing is absolutely critical," added Parsons.

The research will be published in the September 2007 issue of the journal Medicine & Science in Sports & Exercise.