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Old 07-23-15 | 09:47 PM
  #62  
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Carbonfiberboy
just another gosling
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Joined: Feb 2007
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From: Everett, WA

Bikes: CoMo Speedster 2003, Trek 5200, CAAD 9, Fred 2004

Originally Posted by RChung
I have long wondered whether people who have a specific idea about appropriateness for cadence also had a specific idea about appropriate crank torque or appropriate power. If so, I wondered what that would be; if not, I wondered why cadence takes precedence over crank torque or power. You appear to have specific ideas about appropriate cadence so I thought I'd ask you. I am not trying to imply anything. I'm asking a pretty simple question (though if you don't have a specific idea about appropriate crank torque I guess the follow-up question could be a little less simple).
Thanks. Yes, I suppose I do have a specific idea about crank torque. That would be whatever I think my legs can handle for the anticipated duration of the stress. So I've done a 3000' climb at 55 cadence just for fun because I was accompanying a slower rider and still wanted a good leg workout. The low cadence increased crank torque enough to produce adequate leg pain by the end of the climb. Usually I'll climb at 78-82 cadence because my 90%LT power combined with that cadence will cut crank torque enough to allow my legs to keep functioning for a couple hours anyway. I don't want to cut the torque any more by climbing at a higher cadence because my VO2max is crap, always has been.

There's a nice piece somewhere on the interwebs by a Cat 1 rider who was training to set the Mt. Washington record. He was planning to do the whole climb at 95 cadence. If I spun that fast, too much of my aerobic capacity would be going to spin my legs and my climbing power would be way off. I think high VO2max folks tend to climb at a higher cadence because they still have to limit their crank torque like I do (though their numbers are much higher), but have the aerobic capacity to multiply that torque by a much higher cadence to get more power.

So I'm saying that in my mind, power is a function of torque * cadence. If power is limited, then each rider has to find a balance between torque and cadence that suits their physiology and current goal, assuming that gearing is unlimited, which of course it's not, so we can't always choose just what we want even if we know what that is.

Does that make sense?
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