Yesterday, I did 1.5 hours of climbing in the morning with my wife and spent 1.5 hours in the gym in the evening working on upper body, core and some leg work. My hill climbing featured 3 - 10 minute plus climbs with the last one, 6 to 7% grade, in the big ring working on low cadence. IMO, some low cadence climbing or flat land work is excellent to do this time of year to build strength.