Yes, just start your course and your training session before you ride and before you press "Start".
But, from my experience, it's more problematic than you think. It's frustrating that after a workout lap and followed by a rest period, your confronted with a hill to struggle up when you should be resting etc. Likewise, your workout could coincide with going down a hill and no matter how hard you pedal, your not achieving the workout. IE, a sprint leg or high cadence, high heart rate down a steep hill, it does not work.
Basically, you have to find a flat route, but then winds can mess things up.
Or create the workout so that it advances to the next step with pressing the lap button, but even that needs thinking about as you may run out of flat route and end up going downhill or uphill.
Usually, I just ride the same flat route I know and use the lap button and don't bother using a workout and just have the workout in my head.
Another way that I do it mainly for interval or Fartlek training is to use the greatly "Despised" arrows marking a route direction. I will watch the arrows and plan on doing my rest and workout laps as I pass over them, IE sprint from one arrow to the next arrow, or for two arrows etc and then rest for an arrow or two. If your doing a circuit, I also use "Mark and Lap" and use the lap button as I pass over an arrow, then on subsequent laps, I will get a lap que to start a workout etc and when to finish. Off top of my head, the arrows are always about 50 yards apart regardless of how far the map is zoomed in on my 530.
