Originally Posted by
noglider
I'm going to go against conventional wisdom. Sorry. Higher cadences do not reduce the amount of work you do. They increase it. The reason for higher cadence is to reduce risk of injury to your knees. So the trick is to find a cadence that is not too fast that it wastes energy but not so slow that you hurt your knees. My feeling is that for tough climbing, it's way, way below 90 rpm.
I also feel that high cadence climbing does little to build ability to climb. I think it hinders it, because climbing is an opportunity to push harder on the pedals than any other time. I couldn't climb well until I got a fixed gear (66 inches) and didn't have the opportunity to shift down. You don't need a fixed gear to build this skill. You need to choose your gear well.
Plus standing up helps you put more force on the pedals.
I'm willing to talk more about this if you like. I've been cycling seriously for 34 years, and this is what I've learned.
High cadences are fine for flats and downhills but I think they are bad for vigorous climbs.
I agree with this. The fastest climbers in my club are powering up hills in higher gears with slower cadences. On my ultra-distance bike I have very low gears (for when I bonk late in the day on a long, steep hill) and started using them all the time. I couldn't figure out why my performance had plateaued and asked for advice. I was told that riding in these low gears all the time wasn't building up my strength. So, I started riding one gear up, two,... and now I am getting real improvement. Obviously, one needs to build up slowly and be careful about injuries.
When attacking a long, unfamiliar hill, I use a heart monitor and try to dial my HR to a value depending on the total mileage for the day.