But I got some perspective too. Today at the gym, I decided to take it really easy. So I did a 20 min. ride on the stationary bike, with a 2 min. cool down. I didn't even do "Random Hill" but instead I did "manual" and lowered and raised the level so that my heart rate stayed under 120 but my cadence was still over 80.
Then I remembered that when I first started, I had trouble keeping my average mph at 75 and I only went for 30 min. and at a lower level than even the lowest I did today. Plus I used to use the recumbent bikes and now I use the ones you have to hold yourself up on.
So even though this was an "easy" workout for me, I was still doing more than when I was going to the gym working my buns off back in the summer and early fall. I forgot it used to take me 30 min. to go five miles! Now I can do 13 miles in 45 min and with more resistance and hill work too.