I know this probably belongs in another section, but here goes. Everytime I work on high cadence (100+) my knees hurt. This seems strange because I thought higher cadence riding was supposed to be easier on the knees. I think the problem is when I spin my foot floats off the pedal a little. This float is very small, but after 1-2 hours of riding I guess it could add up. When I ride at 90 cadence or so, there is enough force to keep constant contact with the pedal. I guess my question is, do you maintain constant pedal contact when spinning high cadence or just float your foot around in circles? I know this sounds like a stupid question, but when I try to keep constant force with a higher cadence I tire out very quickly. Does this just mean I need to keep working higher cadence so I don't tire out?