With a bazillion flight miles under my belt in everything from a paratroop-rigged C-47 (military version of the DC-3) and Cessnas on up, I have yet to see an exit door that had to be lifted over your head. There are a lot of reasons someone - of either sex and of any age - might have a problem moving his or her arms that high with a suitcase that would not affect strength or mobility below shoulder level. (The aforementioned C-47 had no door, just straps across the opening that wouldn't have stood up to a determined rush. That's one way to solve this problem, but it might lead to other problems with pressurization. Besides, every seat on that plane was an exit seat.)