2 hrs in the flats compared to 2hrs in the mountains? No comparison!
I dunno. I would've agreed until this weekend's ride. Normally I do my long rides up in the mountains outside Boulder, but Saturday I went north (for 4 hours total) and had only one 6 minute climb in the whole route. The ride was focussed on aerobic power and capacity and my power data showed that I put out way more power on this ride than any of my 4 hour mountain rides. Since there were no big descents, I was just hammering away mile after mile after mile.
Now, this weekend I will probably do the same effort but up in the hills, and then I can see how they compare. For the record, I've done plenty of mountain rides where I climbed at that same power level and the end result was lower averages and caolric output
Now, milage in the mountains vs. on the flats, THERE I'd say there's no comparison. I'll take a 20 mile flat ride over a 20 mile climb any day