IMHO, the trend to higher cadences, ala Armstrong, was way oversold, and in part was influenced by racers filled to the gills with EPO that helped them bear the aerobic load imposed by higher cadence.
For most people, their self selected cadence is likely to be just fine.
That said, I do think most new cyclists pedal too low of cadence, and need to work on pedaling in the 80's or 90's most of the time. With some practice, that tends to become their new self selected cadence.
For me, my cadence varies all over the place depending on the circumstance. Fast group ride, I'm likely 90 plus. Race situation, 90's into the hundreds.
Tooling along at a moderate effort, in the 80's. Just going easy, I'm likely in the 70's, and I do a lot of climbing in the 60's, unless it's a short climb, and responding to attacks, where it may be over 100.
So it all depends on the situation. And it's also the reason that my training includes intervals with cadences as low as 50rpm, and as high as 120rpm.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
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