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Pedaling index...could anyone explain this to me?(6 posts)

Pedaling index...could anyone explain this to me?glia
Jan 18, 2004 8:49 PM
My Polar power option gives you a value called the pedaling index which ranges from 0-100. Presumably 100 represents a perfect motion of the crank, hence the lower the number the worse your pedaling. I don't quite get how this works. I was under the impression that a cyclist always excerts the most power in the 1-5 o'clock positon on the crank. That by definition would make the motions weighted heavily towards a left/right pulse of power as the led moves through this position. Also, I have read that one can really not execrt much if any power on the the upstrke of the pedalling. How high should a decent PI be on this unit and if it is as low as mine (27) what need I do to improve it?
re: Pedaling index...could anyone explain this to me?Squint
Jan 19, 2004 2:15 AM
I would just ignore it just like CompuTrainer Spinscan numbers. The Polar can't even measure power accurately. I don't understand why there's such an obsession with pedaling in circles since the fact that the crankarms pivot around a fixed point ensures perfectly circular pedaling...
re: Pedaling index...could anyone explain this to me?glia
Jan 19, 2004 6:30 AM
I would say in their defense that the left right balance works very well on my bike. You conciously put more power on one leg and you see it on the display; one-legged pedaling and you actually shift 100% to that side. So for purposes of balancing your pedalling it actually seems to work.
re: Pedaling index...could anyone explain this to me?Squint
Jan 19, 2004 6:59 AM
You can change your pedaling and see it reflected in Computrainer's Spinscan also but it doesn't make you any faster.
I think we need an expert hereglia
Jan 19, 2004 7:40 AM
OK, I think we are in need for an expert opinion in here. What I hear you say is that the way you pedal doesn't matter. I have read so many times that pedaling techniques make a huge difference and need to be developed over time. That would include left right balance and how well you pull through the "dead spots" on the crank. I recall reading the "scrape your foot" technique. I would simply like to know whether and how I can use the indicators on my power meter to improve my technique. Whether the absolute power displayed is accurate does not matter to me as much.
I think we need an expert hereSquint
Jan 19, 2004 8:11 AM
I think someone needs to do a study where they take a group of national caliber cyclists and a group of slower cyclists and measure the force they apply throughout the pedal stroke. Then we can see if faster cyclists are faster because they're more "efficient" or because they're more powerful, i.e., they simply stomp on the pedals harder.

Oh wait, it's already been done!

See:

Coyle, E.F., Feltner, M.E., Kautz, S.A., Hamilton, M.T., Montain, S.J., Baylor, A.M., Abraham, L.D., & Petrek, G.W. (1991). Physiological and biomechanical factors associated with elite endurance cycling performance. Medicine and Science in Sports and Exercise, 23(1): 93-107.

My recommendation is that you do a 180 and instead concentrate on your power output rather your "pedaling index."