There are a number of studies that make a finer point about cadence. The key "summary article" that I read says that, at lower cadences (at a given power output) cyclists had higher "economy." Economy is defined there as oxygen consumption.
But, at higher cadences, the same cyclists had better fatigue resistance.
Quote from article (found at
http://www.bsn.com/...rticles/cadence.html )
"In summary, laboratory studies indicate that experienced cyclists do not use their most economical or efficient cadences. However, cadences of 90 to 100 rpm are probably beneficial in spite of decreases in economy and efficiency. The explanation proposed here suggests the use of high rpms results in a decrease in average pedal force per revolution and leads to the recruitment of fewer fast-twitch fibers, placing the reliance for muscle power development primarily on the slow-twitch and intermediate fibers. The advantage to the cyclist is there is less likelihood of a rapid accumulation of lactic acid, with the resulting decrease in muscle force production."
So, you have to decide what your strength is for racing. Endurance or Oxygen uptake. Like Frank said, we all have to find our preferred cadence for racing.
Since I have historically been weak on late-ride endurance, I have gravitated to higher cadences. By forcing me into lower cadence riding, I have some degree of confidence that the PCs will help me train my weakness. I still plan to race on regular cranks at ~90 rpm (I rode at 95-100 last year). The idea being the old saw, "Train your weakness; race your strength."
I've got a 20K TT in February that I can compare against the same one I did exactly a year earlier. Results to follow...
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