Originally Posted by DrIsotope

If you feel like taking a day off, do so. If you feel like you're a little tired, but you still want to ride, just pay attention to your intensity.

Originally Posted by caloso

If you're tired, take a day off. That said, what matters isn't mileage so much as time and intensity. Personally, I prefer an easy hour of light spinning to taking a day off.

Originally Posted by caloso

This. I never got any faster till I learned that my hard days were too easy and my easy days were too hard. But, if you don't care about getting fitter and just want to cover the distance, then just ride at the pace that's comfortable.