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SpinScan data

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Power meters
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3 August 2007
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6 August 2007
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jechilt
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  1. Greetings,

    I just had a 3D Biomechanical analysis which provided SpinScan data.

    I was wondering if anyone could give a little insight to how good these numbers are in relation to an average (non-competative) rider. I am trying to get better and maybe next year consider a competative ride but for now, I am just trying to become a good cyclist.

    These were the numbers. Done twice and able to sustain:
    ATA: 90
    SpinScan: 82
    Power: 50/50
    Cadence: 90

    I do a lot of spin classes and focus a lot on pedal stroke. I think that is why my power is pretty consistent at 50/50. I did see a few 49/51 and 48/52 when we really cranked up the watts but I was able to pull the balance back to 50/50 while maintaining a minimum spinscan of 80.

    My goal this year is to get another 1-2mph speed gain over long distances. I have yet to figure out the best training method to do that.

    Thanks for any feedback 🙂

  2. Many of us power junkies feel that chasing pedaling technique is a waste of time. This conclusion is based on a lack of any evidence supporting that "technique" has any effect on efficiency or power production. In fact, there is some evidence that implies that technique is completely irrelevant WRT efficiency and power production.

    Not everyone feels this way of course, but they have yet to show any solid evidence to the contrary (i.e. real peer reviewed scientific evidence)

  3. Looks like you don't have any appreciable imbalances.

    So now you can focus your training on what matters.

    Plus... you could use an Ergomo with peace of mind! 😉

  4. beerco said:

    Many of us power junkies feel that chasing pedaling technique is a waste of time. This conclusion is based on a lack of any evidence supporting that "technique" has any effect on efficiency or power production. In fact, there is some evidence that implies that technique is completely irrelevant WRT efficiency and power production.

    Not everyone feels this way of course, but they have yet to show any solid evidence to the contrary (i.e. real peer reviewed scientific evidence)


    your viewpoint is interesting.

    I struggle with your view. When I think of kinetic energy, which is defined as the work needed to accelerate a body of a given mass from rest to its current velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes.

    Therefore, if a person has a smooth, controlled (consistent) pedal movement, it would seem logical it would be easier to maintain higher levels of speed. Speed is a product of power. The more power or better transfer of power results in higher speed.
    From what I have read by crank manufacturers, college studies, and the sort, there are optimimum crank positions that allow maximum power to be generated. The better your stroke attacks those positions and rotating in a smooth matter not to disturb the kinetic energy flow, the more power and higher speed a person can achieve/maintain.

    I do know when I only push on the pedal, my efficiency drops off and I actually tire faster trying to jump on the pedals every stroke.

    Thanks for your input. I do look forward to hearing other comments too :-)

  5. peterpen said:

    Looks like you don't have any appreciable imbalances.

    So now you can focus your training on what matters.

    Plus... you coulduse an Ergomo with peace of mind! 😉


    I have a Polas CS600. I am still a novice rider. Even so, I really like the CS600. It has provided me a lot of data that I find useful and interesting. I know it is not as fancy as the other devices out there but I really do like it.

  6. jechilt said:

    From what I have read by crank manufacturers, college studies, and the sort, there are optimimum crank positions that allow maximum power to be generated. The better your stroke attacks those positions and rotating in a smooth matter not to disturb the kinetic energy flow, the more power and higher speed a person can achieve/maintain.

    I do know when I only push on the pedal, my efficiency drops off and I actually tire faster trying to jump on the pedals every stroke.

    Thanks for your input. I do look forward to hearing other comments too :-)

    Well here's one, then: you need to read more - a LOT more. 😄 I suggest that you start by tracking down the correct definition of "efficiency" when used in the present context (hint: it doesn't refer to anything you can measure using a CompuTrainer).

  7. jechilt said:

    .....Therefore, if a person has a smooth, controlled (consistent) pedal movement, it would seem logical it would be easier to maintain higher levels of speed. Speed is a product of power. The more power or better transfer of power results in higher speed. ...

    Yeah, that's what you think but when this has been studied the results don't support that logic. Take a look at this paper:

    http://www.edb.utexas.edu/coyle/pdf%20library/(40)%20Coyle,%20Feltner%20et%20al,%20Physiological%20and%20biochemical%20determinants%20of%20elite%20endurance%20cycling%20performance,%20Med%20and%20Sci%20in%20Sports%20and%20Exercise,%2023,%2093-107,%201991.pdf

    And particularly this quote from the discussion:

    "Although the "elite-national class" cyclists
    (group 1) were not different from the "good-state class"
    cyclists (group 2) regarding VO2maxor lean body weight,
    group 1 was able to generate 11% more power during
    the 1 h performance test than group 2 (P < 0.05), and
    they maintained a 10% higher bicycling velocity for 40
    km (P < 0.05). The higher power output was produced
    primarily by generating higher peak vertical forces and
    torque during the cycling downstroke and not by increasing
    the effectiveness of force application to the
    pedal.
    "

    Anyway, there are few if any studies that show that more circular pedal strokes are actually better and at least this study that finds the opposite to be true.

  8. acoggan said:

    Well here's one, then: you need to read more - a LOT more. 😄 I suggest that you start by tracking down the correct definition of "efficiency" when used in the present context (hint: it doesn't refer to anything you can measure using a CompuTrainer).


    while I appreciate your comment, could you at least help me along the process and provide me some links to what I "should" be reading more of?
    Sure, I can search on my own, but if you are already aware of good info, it would be great if you point me in the right direction.

  9. daveryanwyoming said:

    Yeah, that's what you think but when this has been studied the results don't support that logic. Take a look at this paper:

    edb.utexas.edu(40)%20Coyle,%20Feltner%20et%20al,%20Physiological%20and%20biochemical%20determinants%20of%20elite%2

    And particularly this quote from the discussion:

    "Although the "elite-national class" cyclists
    (group 1) were not different from the "good-state class"
    cyclists (group 2) regarding VO2maxor lean body weight,
    group 1 was able to generate 11% more power during
    the 1 h performance test than group 2 (P < 0.05), and
    they maintained a 10% higher bicycling velocity for 40
    km (P < 0.05). The higher power output was produced
    primarily by generating higher peak vertical forces and
    torque during the cycling downstroke and not by increasing
    the effectiveness of force application to the
    pedal."

    Anyway, there are few if any studies that show that more circular pedal strokes are actually better and at least this study that finds the opposite to be true.


    makes me feel like the money i spent to see how well I was focusing on good form is/was a waste.

  10. jechilt said:

    makes me feel like the money i spent to see how well I was focusing on good form is/was a waste.


    At the very least, you started this conversation and learned something from it. No one said learning was free. :p

    -Eric

  11. jechilt said:

    makes me feel like the money i spent to see how well I was focusing on good form is/was a waste.

    Not necessarily. Both groups generated most of their power on the downforce. This doesn't meant that there are slight increases in power that can be squeezed out by actually training to generate power in the the other three parts of the pedal stroke. All this study shows is that the fitter riders have trained by applying most of their power on the downstroke, as do most all of us. It's what comes most naturally, not necessarily the absolute most efficient way.

    A better study would take two groups of riders of equal experience, training and ability and give 'em some power cranks or some spin regime, give the other group traditional cranks, train them identically, then see what happens.

  12. bbrauer said:

    This doesn't meant that there are slight increases in power that can be squeezed out by actually training to generate power in the the other three parts of the pedal stroke.

    Do you have any evidence that this is possible? Do you have a theory why it might be possible?

  13. with what we have discussed so far, is it really worth getting a power training book? If so, which do you recommend?

  14. jechilt said:

    with what we have discussed so far, is it really worth getting a power training book? If so, which do you recommend?

    If your goals are to get the most bang for the time you spend on your bike, then yes, a power training book and powermeter are definitely worth it.

    acoggan's book http://www.amazon.com/Training-Racing-Power-Meter-Hunter/dp/1931382794/ref=pd_bbs_sr_1/105-6400740-1254053?ie=UTF8&s=books&qid=1186343910&sr=8-1 wraps it all up in a nice neat package.

    While you're waiting for it to arrive, check out: www.trainwithpower.net

  15. jechilt said:

    Greetings,

    I just had a 3D Biomechanical analysis which provided SpinScan data.

    I was wondering if anyone could give a little insight to how good these numbers are in relation to an average (non-competative) rider. I am trying to get better and maybe next year consider a competative ride but for now, I am just trying to become a good cyclist.

    These were the numbers. Done twice and able to sustain:
    ATA: 90
    SpinScan: 82
    Power: 50/50
    Cadence: 90

    I do a lot of spin classes and focus a lot on pedal stroke. I think that is why my power is pretty consistent at 50/50. I did see a few 49/51 and 48/52 when we really cranked up the watts but I was able to pull the balance back to 50/50 while maintaining a minimum spinscan of 80.

    My goal this year is to get another 1-2mph speed gain over long distances. I have yet to figure out the best training method to do that.

    Thanks for any feedback 🙂


    A high SpinScan number is cool but power is what gets you down the road (and up the hill). Focus on increasing your sustainable Watts/kg over durations pertinent to your chosen events and you'll get there.

    I've had a CT since 2002 and can't even recall how many hundred hours of usage right now. I highly recommend them but I haven't even hooked up the cadence sensor for over two years. IOW, I don't get to use SpinScan much. last time I did check it -- was around 60 I think when pushing hard. Could be higher, could be lower, but the power has increased and really that's pretty much all that matters.

  16. jechilt said:

    could you at least help me along the process and provide me some links to what I "should" be reading more of?

    www.pubmed.gov

  17. bbrauer said:

    A better study would take two groups of riders of equal experience, training and ability and give 'em some power cranks or some spin regime, give the other group traditional cranks, train them identically, then see what happens.

    Except that you probably couldn't do it. PCs, AFAIK, require quite a lengthy adaptation period, which means that the two groups could not train identically.

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