There is evidence to suggest that healthy men and women experience respiratory system limitations during exercise, such as respiratory muscle fatigue, a limited ability to exhale, and an abnormal exchange of oxygen and carbon dioxide in the lungs. Young active women may be particularly susceptible to these limitations due to their inherently smaller lungs and airways compared to men of equal stature. Unfortunately, there have been few studies aimed at understanding how the female respiratory system responds during exercise. Since healthy young women are predisposed to these limitations during exercise, then healthy elderly women may be particularly vulnerable due to the decline in lung function that occurs as a result of the normal aging process. This decline occurs because of a reduction in “elastic recoil,” which is the ability of the lungs to stretch and inflate. Jordan Guenette is studying the relationships between the respiratory system, exercise, gender, and healthy aging. His goal is to identify the respiratory limitations women face as they age. This information could be used to design exercise rehabilitation programs tailored to meet the needs of different patient populations.