Does anyone know if it's possible to set up an interval workout using running power as a target type? When I add a step to a workout, and look under target type, the only choices are pace, cadence, heart rate zone, or custom heart rate. Since this watch can do running power, it seems like it should be possible to use that as a training zone, but it sure doesn't seem possible. Am I missing something? Maybe there's some way to do this with 3rd party functionality?