Women, on average, have a more difficult time breathing during vigorous exercise because their airways are smaller, according to findings published in The FASEB Journal (2020; doi:10.1096/fasebj.2020.34.s1.05355). This may help explain why women experience airway disorders like asthma differently from men.

“The amount of work the respiratory muscles have to do to breathe a given volume is greater in women,” said Paolo Dominelli, PhD, principal study investigator and assistant professor at the University of Waterloo in Ontario. “It is thought that this is due to women having smaller airways than men, which causes the airflow resistance to be higher.”

Researchers note that this gender difference is a generalization; airway size can differ among individuals. For example, while men on average have larger airways, a man and a woman of similar height may have similarly sized airways.