October 26, 2009
A professor at Johnson State College (JSC) is spearheading a study that may change the way people with asthma view exercise.
Dr. Hans Haverkamp, an assistant professor in JSC's Environmental and Health Sciences Department, is conducting research on people with mild-to-moderate asthma to determine whether having asthma symptoms affects their ability to exercise. This is the first study of its kind that measures multiple breathing variables and lung functions during exercise, in both asthmatic and non-asthmatic humans - in a comprehensive way. The project is being funded by a grant from the Vermont Genetics Network.
Traditional thinking suggests that individuals who are experiencing asthma symptoms such as constriction, or narrowing, of the airways would find it harder to exercise than those without symptoms. Haverkamp, an expert on the pulmonary system and breathing during exercise, believes otherwise.
While this turns traditional thinking on its head, he already has preliminary data to support his hypothesis that constricted airways do not affect a person's ability to exercise.
Haverkamp began his two-year study in the summer of 2008 and, with the assistance of JSC students, has worked extensively with subjects since then. Half of his subjects have mild to moderate asthma, while the other half serve as "control subjects" without asthma.
Following various interventions that improve, reduce or make no change to their lung function, subjects undergo numerous tests while exercising strenuously on a bicycle. While it seems natural that changes in lung function would affect a subject's ability to exercise, Haverkamp has found no difference to date.
"Subjects exercised the exact same amount of time, no matter what," he says. "Whether they were broncho-constricted or broncho-dilated, everything looked the same."
The reason, he believes, is that whether a person has asthma or not, their lung function immediately changes when they exercise.
"Exercise powerfully dilates the airways, very rapidly," Haverkamp says. "So it doesn't matter what things look like beforehand- exercise appears to lead to the same airway size, no matter what."
To make these determinations, he and his students are using techniques that have not been used before in a comprehensive way. For example, every subject is fitted with an esophageal catheter, which allows the researchers to measure their lung pressure with great precision.
"For every breath," Haverkamp says, "I can measure resistance to breathing before, during and after exercise."