On my trainer, strictly time :P total miles is nada zippo. I do play a game on my trainer to keep me entertained. I want to see how hot I can get my mags by the end of the workout. I keep track of the time in different "zone".

Out on the road, typical distance is anywhere from 25-45 miles. Don't keep a log of time nor miles. I usually go out with idea of how many intervals I want to do or how many hill climb sets I want to do... So not paying much attention to miles nor time.

What I used to do after HRM became available was to watch my HR and keeping it in the "zone" during the alloted time.

Rest day is bit different I try to log in about 10 easy flat miles. No exertion really.

I just don't like to be a slave to my cycling computer anymore. But just too curious so I'm still look at my HR and compare to what I'm feeling.

But if you are just starting, keep track of miles and times.