Dear Dr. K: Dear Dr. K.: My husband and I both have allergies and we are both triathletes. When we exercise my husband’s nasal congestion always improves, while mine seems to get worse. What’s going on?
The answer to your question is statistics.
Your husband is on the good side of statistics and you are on the bad side. What I mean is that in the majority of people with allergies exercise helps open the nasal passages. It does this by two main mechanisms: neurologic and chemical. In most persons, exercise increases preferentially the sympathetic nerves that control blood vessel size, constricting these blood vessels, and thus, improving nasal patency (being open or expanded).
Exercise also releases “adrenal-like” chemicals that exert the same effect on the nasal blood vessels.
In a small number of people, exercise preferentially stimulates the parasympathetic nerves, which dilate nasal blood vessels and cause congestion. This phenomenon is called exercise-induced rhinitis. It is similar to a related phenomenon in asthmatics called exercise-induced-bronchospasm.
One predisposing factor to exercise-induced-rhinitis is deviation of the nasal septum. Apparently, people with septal deviation have a chronic disparity in air flow through the two nostrils. For some reason, this makes the parasympathetic nerves more sensitive, and thus their adverse response to exercise.