Graph of pedaling power and efficiency

Discussion in 'Cycling Equipment' started by Doug Goncz, Mar 10, 2003.

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  1. Doug Goncz

    Doug Goncz Guest

    Hello all. I haven't been by here in a while.

    There was a bicycle science newsletter in the early 80's that had a graph of pedaling power and
    efficiency, with points along a "breaking wave" shaped curve, labeled every 10 rpm of pedaling pace.
    The peak efficiency on the graph was about 90, the peak power, about 120.

    I have read in Marks' Standard Mechanical Handbook for Mechanical Engineers that the peak efficiency
    occurs at half maximum effort and one quarter maximum pace. Could this be a misprint? Or does it
    make sense to pedal slower and harder. Do most people pedal lighter and faster to avoid the feeling
    of leg stress, transferring the load to the heart and lungs?

    Can you provide, please, a link to a graph in *.pdf or a web page, showing more recent results for
    pace, power, and efficiency?

    Sorry I couldn't find an exercise or bicycle ergonomics newsgroup. Any particular group you could
    recommend for this search?

    Yours,

    Doug Goncz, Replikon Research, Seven Corners, VA (truncate pee dot mil antispam for mail)
    http://users.aol.com/DGoncz http://groups.google.com/groups?as_q=DGoncz "Function, Funding, Form,
    Fit, and Finish"
     
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  2. Kinkycowboy

    Kinkycowboy Guest

    On 10 Mar 2003 14:18:56 GMT, [email protected] ( Doug Goncz ) wrote:

    >Hello all. I haven't been by here in a while.
    >
    >There was a bicycle science newsletter in the early 80's that had a graph of pedaling power and
    >efficiency, with points along a "breaking wave" shaped curve, labeled every 10 rpm of pedaling
    >pace. The peak efficiency on the graph was about 90, the peak power, about 120.
    >
    >I have read in Marks' Standard Mechanical Handbook for Mechanical Engineers that the peak
    >efficiency

    peak efficiency of what? Pedalling power and efficiency is not very much to do with Mechanical
    Engineering north of the cleats.

    >occurs at half maximum effort and one quarter maximum pace. Could this be a misprint? Or does it
    >make sense to pedal slower and harder. Do most people pedal lighter and faster to avoid the feeling
    >of leg stress, transferring the load to the heart and lungs?
    >
    >Can you provide, please, a link to a graph in *.pdf or a web page, showing more recent results for
    >pace, power, and efficiency?

    Read these if you haven't already http://www.me.utexas.edu/~neptune/Papers/msse32(7).pdf
    http://www.bsn.com/Cycling/articles/cadence.html

    I saw a report in Cycling Weekly (UK) in the past year suggesting peak power for elite track
    sprinters at around 150rpm, but I don't have it to hand.

    >
    >Sorry I couldn't find an exercise or bicycle ergonomics newsgroup. Any particular group you could
    >recommend for this search?
    >
    >
    >
    >Yours,
    >
    >Doug Goncz, Replikon Research, Seven Corners, VA (truncate pee dot mil antispam for mail)
    >http://users.aol.com/DGoncz http://groups.google.com/groups?as_q=DGoncz "Function, Funding, Form,
    >Fit, and Finish"

    Kinky Cowboy

    *Your milage may vary Batteries not included May contain traces of nuts.
     
  3. Gary German

    Gary German Guest

    " Doug Goncz " <[email protected]> wrote in message
    news:[email protected]...
    > Hello all. I haven't been by here in a while.
    >
    > There was a bicycle science newsletter in the early 80's that had a graph
    of
    > pedaling power and efficiency, with points along a "breaking wave" shaped curve, labeled every 10
    > rpm of pedaling pace. The peak efficiency on the
    graph
    > was about 90, the peak power, about 120.
    >
    > I have read in Marks' Standard Mechanical Handbook for Mechanical
    Engineers
    > that the peak efficiency occurs at half maximum effort and one quarter
    maximum
    > pace. Could this be a misprint? Or does it make sense to pedal slower and harder. Do most people
    > pedal lighter and faster to avoid the feeling of
    leg
    > stress, transferring the load to the heart and lungs?
    >
    > Can you provide, please, a link to a graph in *.pdf or a web page, showing
    more
    > recent results for pace, power, and efficiency?
    >
    > Sorry I couldn't find an exercise or bicycle ergonomics newsgroup. Any particular group you could
    > recommend for this search?
    >
    >
    >
    > Yours,
    >
    > Doug Goncz, Replikon Research, Seven Corners, VA (truncate pee dot mil antispam for mail)
    > http://users.aol.com/DGoncz http://groups.google.com/groups?as_q=DGoncz "Function, Funding, Form,
    > Fit, and Finish"

    You might find what you're looking for at:

    http://www.analyticcycling.com/

    Gary G.
     
  4. This topic resurfaces from time to time in various guises and stems from some misconceptions about
    efficiency. If you define efficiency as it is normally used i.e. useful work done for energy
    expended (like miles per gallon for a car), then this is something of little interest to the cyclist
    who normally has almost unlimited stored energy (in the form of fat). What concerns the cyclist is
    not efficiency but avoidance of fatigue. This is best accomplished by working the leg muscles
    rapidly at relatively low loads because the human body seems capable of the highest total work that
    way (let the physiologists tell you why). Note, this is talking about the total work accomplished,
    not the rate of doing work (power). Try a simple experiment: find the toughest hill you know and see
    how many times you can climb it in a low gear with a fast spin. Then, on a different day, when you
    have had a chance to recover, try again in the biggest gear on your bike. Assuming you can get up
    the hill at all by the second method, which of the two techniques would allow you to climb the hill
    more times before exhaustion sets in? In terms of efficiency, it may be that grinding up in a huge
    gear uses less energy (calories) and is therefore more efficient, but is that really important to
    the rider? Endurance cyclists tend to pedal lighter and faster because that better postpones the
    crippling muscle fatigue that will eventually force them to stop even though they may well squander
    more calories by this approach.

    Nigel Grinter

    [email protected] ( Doug Goncz ) wrote in message
    news:<[email protected]>...
    > Hello all. I haven't been by here in a while.
    >
    > There was a bicycle science newsletter in the early 80's that had a graph of pedaling power and
    > efficiency, with points along a "breaking wave" shaped curve, labeled every 10 rpm of pedaling
    > pace. The peak efficiency on the graph was about 90, the peak power, about 120.
    >
    > I have read in Marks' Standard Mechanical Handbook for Mechanical Engineers that the peak
    > efficiency occurs at half maximum effort and one quarter maximum pace. Could this be a misprint?
    > Or does it make sense to pedal slower and harder. Do most people pedal lighter and faster to avoid
    > the feeling of leg stress, transferring the load to the heart and lungs?
    >
    > Can you provide, please, a link to a graph in *.pdf or a web page, showing more recent results for
    > pace, power, and efficiency?
    >
    > Sorry I couldn't find an exercise or bicycle ergonomics newsgroup. Any particular group you could
    > recommend for this search?
    >
    >
    >
    > Yours,
    >
    > Doug Goncz, Replikon Research, Seven Corners, VA (truncate pee dot mil antispam for mail)
    > http://users.aol.com/DGoncz http://groups.google.com/groups?as_q=DGoncz "Function, Funding, Form,
    > Fit, and Finish"
     
  5. Jon Isaacs

    Jon Isaacs Guest

    >Assuming you can get up the hill at all by the second method, which of the two techniques would
    >allow you to climb the hill more times before exhaustion sets in?

    This really depends on who you are and how fast you are riding.

    In terms of efficiency, it may be that grinding
    >up in a huge gear uses less energy (calories) and is therefore more efficient, but is that really
    >important to the rider? Endurance cyclists tend to pedal lighter and faster because that better
    >postpones the crippling muscle fatigue that will eventually force them to stop even though they may
    >well squander more calories by this approach.

    Endurance riders tend to be lightly muscled riders with mostly slow twitch muscles. This means they
    don't have the strength to push those gears up the hills and their muscles are more tuned to that
    sort of riding.

    But other riders who may have a majority of fast twitch muscle may find that pushing a bigger gear
    allows their muscles to fatigue less and at the same time use less oxygen and fuel.

    Jon Isaacs
     
  6. A Muzi

    A Muzi Guest

    " Doug Goncz " <[email protected]> wrote in message
    news:[email protected]...
    > Hello all. I haven't been by here in a while.
    >
    > There was a bicycle science newsletter in the early 80's that had a graph
    of
    > pedaling power and efficiency, with points along a "breaking wave" shaped curve, labeled every 10
    > rpm of pedaling pace. The peak efficiency on the
    graph
    > was about 90, the peak power, about 120.
    >
    > I have read in Marks' Standard Mechanical Handbook for Mechanical
    Engineers
    > that the peak efficiency occurs at half maximum effort and one quarter
    maximum
    > pace. Could this be a misprint? Or does it make sense to pedal slower and harder. Do most people
    > pedal lighter and faster to avoid the feeling of
    leg
    > stress, transferring the load to the heart and lungs?
    >
    > Can you provide, please, a link to a graph in *.pdf or a web page, showing
    more
    > recent results for pace, power, and efficiency?
    >
    > Sorry I couldn't find an exercise or bicycle ergonomics newsgroup. Any particular group you could
    > recommend for this search?

    I am not an expert but perhaps you are referring to some of the charts in Whitt & Wilson's
    "Bicycling Science" (MIT, '74)?

    --
    Andrew Muzi http://www.yellowjersey.org Open every day since 1 April 1971
     
  7. [email protected] (Jon Isaacs) wrote in message
    news:<[email protected]>...
    > >Assuming you can get up the hill at all by the second method, which of the two techniques would
    > >allow you to climb the hill more times before exhaustion sets in?
    >
    > This really depends on who you are and how fast you are riding.
    >
    > In terms of efficiency, it may be that grinding
    > >up in a huge gear uses less energy (calories) and is therefore more efficient, but is that really
    > >important to the rider? Endurance cyclists tend to pedal lighter and faster because that better
    > >postpones the crippling muscle fatigue that will eventually force them to stop even though they
    > >may well squander more calories by this approach.
    >
    > Endurance riders tend to be lightly muscled riders with mostly slow twitch muscles. This means
    > they don't have the strength to push those gears up the hills and their muscles are more tuned to
    > that sort of riding.
    >
    > But other riders who may have a majority of fast twitch muscle may find that pushing a bigger gear
    > allows their muscles to fatigue less and at the same time use less oxygen and fuel.
    >
    > Jon Isaacs

    It's all relative: what may be an impossible pedal load for a spindly climber is only a mild workout
    for a powerful track sprinter. But each has their limit, and there comes a point for both where the
    pedling effort becomes high enough to promote accelerated fatigue.

    Nigel Grinter
     
  8. [email protected] (Jon Isaacs) wrote in message
    news:<[email protected]>...
    > >It's all relative: what may be an impossible pedal load for a spindly climber is only a mild
    > >workout for a powerful track sprinter. But each has their limit, and there comes a point for both
    > >where the pedling effort becomes high enough to promote accelerated fatigue.
    > >
    > >Nigel Grinter
    >
    > I think the issue here though is which reduces ones endurance more. My point is that pushing the
    > bigger gear may allow the track sprinter to climb more effectively for a longer period of time if
    > she/he were trying to spin up the hill.
    >
    > jon isaacs

    I don't think we are necessarily saying different things. My point is that our muscles can perform
    most total work against relatively light loads. What constitutes 'light' depends on the individual.
    But push too hard, whether a sprinter or a climber, and your muscles will say 'enough' before they
    have done as much work as they could do when pushing less hard for a longer period of time.

    Nigel Grinter
     
  9. [email protected] (Jon Isaacs) wrote in message
    news:<[email protected]>...
    > >I don't think we are necessarily saying different things. My point is that our muscles can
    > >perform most total work against relatively light loads.
    >
    > I think we are saying different things. I am saying that for some riders with some muscle types,
    > it may be desireable to push against harder loads at lower cadences rather than lighter loads at
    > higher rpms. I find that when climbing my endurance is best at quite low rpms, mashing away at 40
    > rpm. Try to maintain the same speed at 80 rpm and I will tire more quickly.
    >
    > I am not an "endurance athlete", I am one of those fast twitch muscle guys.
    >
    > jon isaacs

    I have been assuming that all the activities we talked about are aerobic. For someone climbing a
    constant slope at a constant speed, the rate of work increases as their cadence increases when they
    shift to a lower gear. If that extra work output takes them over their anaerobic threshold, they
    will certainly conk out more rapidly, whatever their muscle type. I was only considering activities
    that fall within the aerobic range. At 40 rpm you are maybe right on your anaerobic threshold and
    hence any increase in cadence while maintaining the same speed is going to cause you to fatigue
    rapidly. But what if you upped you cadence to 80 rpm without changing you power output? You would
    certainly be climbing more slowly, but under which set of conditions - 40 or 80 rpm - could you
    climb the bigger mountain? This is the core of what we are debating. Where are the physiologists
    when you need them?

    Nigel Grinter
     
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