One way to do it (if you're not using heart rate to determine zones) is the following:
Zone 1 - easy / recovery pace
Zone 2 - slow but a little harder than zone 1
Zone 3 - Tempo / Threshold workouts
Zone 4 - Aerobic intervals
Zone 5 - Repetitions*
*I'm using the Jack Daniels interpretation here...
@Hammer, I think those repetitions are a different kind of zone entirely.
Well my watch does have a heart rate monitor now, not that I've set up any zones. I think that was about what I was doing just some longer interval sessions were also logged as zone 3
Easy to be mistaken between the two