The latest research has found a simple explanation on why young women are more likely to report greater shortness of breath than young men, regardless of how healthy their lungs were.

For the study, the researchers had 50 healthy, non-smoking men and women between the ages of 20 and 40 exercise on a stationary bike. Participants were asked to rate their breathlessness on a scale of 1 to 10, while their physiological responses (like what was going on in their diaphragms) were also monitored.

Not only did the women report greater shortness of breath, but their respiratory muscles were also working harder than the guys' were. Basically, this all boils down to biology, since women's lungs are smaller than our male counterparts.
"Biologically, women's lungs are smaller. Their airways are narrower, their breathing muscles are naturally weaker than men's. So their muscles have to be activated more aggressively and have to be engaged more actively by the nervous system in order to move air in and out of the lungs during exercise."
So even if you and your guy friend are doing the same workout, your lungs may have to work a little harder than his. Sounds pretty unfair, if you ask us.

[Women's Health]