Thread: Watts/Cadence
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Old 12-08-23, 10:01 AM
  #44  
chaadster
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Originally Posted by RChung
This paper's study subjects are world class and elite track athletes (so not really relevant to us) but what's interesting is that "field-derived" (i.e., velodrome) and "laboratory-derived" (i.e, on a stationary bike) cadence and max power were different. This means that the "load characteristics" of the stationary bike and the velodrome track were also different. World-class track athletes are an edge case but it suggests that "freely chosen" cadence and torque may not be directly transferrable between lab to road.

https://www.tandfonline.com/doi/full...4.2023.2288435
Relatedly, and perhaps interestingly, the ride data I posted upthread was an outdoor ride, while on Wednesday, I did a stationary ride on the old PowerTap 300Pro (or Pro 300; I forget) and looked at the PowerAgent data, including torque. I was just doing 5min blocks of L3 and L4 (so Tempo and Threshold) alternating cadence from 80-85, 90-95, 85-90rpm and back, so it was easy to see to torque values. As it does, PowerAgent reports in Nm, but I was seeing values like 7.5Nm-8nm (L3 and L4 respectively, ~250w and ~300w) which convert to only around 5.9ft-lbs. It seems either like something is way out of whack in either one or both of the readings, or it's an extreme example of the paradigm proposed in the report.

I didn't have time to dig bag in ancient files from the PowerTap (going back to 2011) to compare torque values, but maybe I'll try to do that some day. I don't have a computer with PowerAgent anymore, but my coach has one in the studio, so it should be possible.
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