Ellipticals always have destroyed me, quickly. So much so I never got on one if someone else was near by because I did not want to get embarrassed by having to get off of it after 5 minutes with jello legs ready to pass out!
The longest I've only ever gone is 8.5 minutes. I've been working out really hard to get my leg strength up.
I went to the gym this morning at 0530 before anyone else was there and decided to see what I could do.... 21 minutes!
It AMAZES me to see how stamina and abilities change.... something that 3 weeks ago would have NEVER happened, I did today - and it wasn't unbearably hard!!