Was meant to be 3hrs low Z2 with sprints, but due to poor route choice messed up, so I did the 3hrs with sprints( all seated). I am not skilled enough at standing sprinting yet to do them on a main road, I never feel that I am in full control of the bike, something I need to work on, but no drama. Anyway, I just rode my bike without going daft and focussed on higher cadence which was 89 for the 3 hours....pleased with that.