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  1. #26
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    If pushing down the pedals its the efficient way then why pro use clipless shoes if they are just pushing down ? The efficient pedalingway to me is pushing down with my toes up and heel down ( not fully down but in the middle ) and then toes down heel up as you get into the up stroke .

  2. #27
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    Quote Originally Posted by otaner142 View Post
    If pushing down the pedals its the efficient way then why pro use clipless shoes if they are just pushing down ? ... .
    I think it was explained in a previous post, but the reason is it securely locates your foot in your preferred position, whether you're seated or out of saddle.

    You'll especially appreciate this if you're ever in all-out sprint, out of saddle, turning the cranks 130+ rpm ;-)

    But even for a semi-serious recreational rider, holding the foot location is a big factor for comfort and consistency of power output.

  3. #28
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    There is no doubt in my mind that people pull the pedals while sprinting and even at other times getting the cranks around with a forward and backward effort other than the standard down or up effort.
    If riding was just about pushing pedals it wouldn't matter if you rode with huge stack height in your shoes and cleats right? I say the stack makes pulling or pushing over the dead spot harder...assuming anyone does that, which I know at certain times I do.
    I will sometimes consciously use muscles other than the downward force ones...a subtle pull at the bottom and roll over the top. It may be inefficient to use these smaller muscles for any length of time, they aren't as strong, but for short periods they give a slight rest to the mainly used leg muscles. I'll occasionally pedal purely with no downward motion and I can keep at 20mph on a flat for a bit of time.

    The study cited, while I didn't look into it, might be limited to a certain restricted activity. I bet if they were to include a full days riding they'd find a forward, backward, and upward effort.
    Just look at cyclist's legs, there's a lot more developed muscles than just those used for pushing down and they aren't just for stability. I've got hip muscles from cycling which girls like to hold onto. You could have them too

  4. #29
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    Quote Originally Posted by hummina shadeeba View Post
    ... The study cited, while I didn't look into it, might be limited to a certain restricted activity. I bet if they were to include a full days riding they'd find a forward, backward, and upward effort. ...
    The 1991 Coyle study and graph posted earlier, was from a 40km TT on a lab ergometer cycle. Times ranged 51-60 minutes. They were instructed to pedal at maximal sustainable or "race" pace.


    Quote Originally Posted by hummina shadeeba View Post
    ... Just look at cyclist's legs, there's a lot more developed muscles than just those used for pushing down and they aren't just for stability. I've got hip muscles from cycling which girls like to hold onto. You could have them too
    My entire legs are very low body fat%, which emphasizes the underlying muscle structure. Eg, I don't think I have any particular strength in my calves, and in fact the calves are quite skinny, and to non-cyclists the calves might even be described as "ripped".

    re "hip muscles", the gluteus muscle group is the largest single muscle group in the body and does get heavily recruited by experienced and/or "trained" cyclists ... even though to most people it's the quadriceps feeling the fatigue , probably because the quadriceps are a smaller muscle.

    Interestingly, in the Coyle 1991 study, they also measured leg circumference at lower, mid, and upper thigh.
    There was a very slightly bigger leg in the national level vs state level athletes, but it was under 2%.

    There was no obvious correlation between leg size and TT performance and output wattage.

    There was a very strong & direct correlation between vO2 and TT performance, and the national-level cyclists were able to sustain a higher % of vO2max during the TT -- cycling is an aerobic, not a strength, sport!

  5. #30
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    cycling is commonly known as aerobic but there are a lot of people who win races with a bad ass power sprint that looks far from aerobic. And I bet they're pulling up and possibly every other way on the pedals at moments. We may be comparing apples to oranges with TT vs road racing though. I wonder if a there's a similar study using huge cranks in which we could see some differences. I surmise that if you pushed a huge crank and you only were exerting effort when pushing down a rider would end up with a faster time. With the simplified we-only-push-down view it's just a larger lever with more leverage and it seems to follow that they would go faster. Maybe they would but I suspect the rest of the crank circle's rotation has relevance and it would show.
    Maybe no power shows in the up, forward, or back stroke in this study because this effort is so well timed after such repetition that it's just enough to pull the weight of the leg up and around the circle.
    Last edited by hummina shadeeba; 12-21-2013 at 11:06 AM.

  6. #31
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    Quote Originally Posted by hummina shadeeba View Post
    cycling is commonly known as aerobic but there are a lot of people who win races with a bad ass power sprint that looks far from aerobic. And I bet they're pulling up and possibly every other way on the pedals at moments....
    Oh yes, for sure ... but the very high power, anaerobic energy system can only operate for typically 12-20 seconds.

    Quote Originally Posted by hummina shadeeba View Post
    ... I wonder if a there was a similar study with huge cranks you could see some differences and what those differences mean. If you pushed a huge crank, and you only were exerting effort when pushing down, why wouldnt they just simply end up with a faster time? With the simplified we-only-push-down view it's just a larger lever with more leverage. But I suspect the rest of the crank circle's rotation has relevance and it would show.
    No free lunch:
    Power = cadence x torque = cadence x force x lever arm length.

    With huge gearing or long cranks, your cadence will decrease and there will be no net increase in power. In fact, sustainable power will decrease at some point, because big gear recruits more fast twitch muscle and those tire more easily.

    I observe both these 2 effects on my power data, and I'm pretty sure I am "typical".

  7. #32
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    "With huge gearing or long cranks, your cadence will decrease and there will be no net increase in power. In fact, sustainable power will decrease at some point, because big gear recruits more fast twitch muscle and those tire more easily."

    I wouldve thought a big gear and/or it's slow cadence would recruit slow twitch muscles not fast

    A longer lever will give you more power or force (not sure on the proper terminology) and the only thing hindering this is the rest of the circle which the crank will have to go. This "rest of the circle" is an obstacle in that it slows your cadence (bigger circle is a longer distance) and with the bigger circle and necessary lowering of saddle, the optimum crank position, 3o'clock, will move away from the rider's optimum leg angle... at the extreme the rider's knee would be too bent to put out much effort.
    these are the obstacles to a longer crank as I see it.
    With a longer crank it makes more sense that a rider would use the rest of the circle as there would be greater leverage all around and nowhere on the circle except maybe at 5 to 6 would they be able to push with a mostly elongated and powerful leg while with a shorter crank they could get good leg extension from possibly 3 to 6. The ideal pedaling position between 3 and 6 would be less valuable and the rest of the circle would be of greater use though.

    And what about those cool cranks that worked independently? They develop the other muscles other than just the pushing ones as you have to pull the pedal all around back to the top. Do you believe developing such muscles is valueless?
    And as I said before maybe the study doesn't contradict the idea of pulling on the pedals, it's just that pulling enough to unweight the foot is all that is being shown done. This would follow with the data as at the harder levels there was even a down-push on the backside, that would be counter productive, possibly from these smaller muscles being used for the upstroke being fatigued
    And I also dont think that my hip muscles and any other leg muscles I have bulging out are the result of just being more defined.
    My legs can be exhausted after a ride to the extent I'll be having a hard time lifting my feet and tripping on things.

  8. #33
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    I imagine someone will come out with a crank someday in the future that will enable the crank lever to keep the pedal in the ideal 3 to 6 0'clock position constantly. This will allow the rider to be in a most powerful/efficient leg angle continuously. maybe.

  9. #34
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    Quote Originally Posted by hummina shadeeba View Post
    ... I wouldve thought a big gear and/or it's slow cadence would recruit slow twitch muscles not fast.. .
    Not so, that's a common misunderstanding.

    "fast twitch" is engaged when doing explosive, very high strength activity. Think of jumping from the ground, up onto the top of a 3 ft high table. Or, a maximum effort "jump" on the first couple pedal strokes of a sprint.

    The high strength needed to turn over a 53-12 gear going uphill, recruits mostly the easily tired, fast twitch muscles even though you are turning pedals very slowly.

    When have you ever seen a pro cyclist trying to win a long, multi-mile climb of 6-10% grade, while pedaling at 60 rpm? I'd safely say, "Never".

  10. #35
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    Quote Originally Posted by hummina shadeeba View Post
    ... And what about those cool cranks that worked independently? They develop the other muscles other than just the pushing ones as you have to pull the pedal all around back to the top. Do you believe developing such muscles is valueless? .."
    Those Power Cranks™ don't work. Not a single, independent lab study has shown they offer any training improvement.

    By "independent" I mean, isn't affiliated with or receiving payment from the manufacturer.

  11. #36
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    ok you say they're called slow twitch muscles and lots of us seem to be calling them fast twitch. I'll agree on that but the rest I will contest.


    Just as a lab hasn't shown power cranks work..none have shown they don't, as far as I can read, and there are a lot of people out there who feel they're better because of them.

    But the issue of pedaling while possibly pulling over the top, along the bottom, and around the backside of the pedaling circle is still debatable even with this study having been done as I see it. As I wrote regarding the study: generally there is a lack of weight pushing down on the pedal on the backside of the pedal stroke and this could demonstrate muscles being used to lift just the leg's weight. In fact I can't imagine what else to attribute the lack of a twenty-something pound leg's resistance showing up. And then when the rider is at his limit these weaker muscles lifting the leg are exhausted and then there is weight being shown on the pedal.
    Possibly?

  12. #37
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    Quote Originally Posted by hummina shadeeba View Post
    ok you say they're called slow twitch muscles and lots of us seem to be calling them fast twitch. I'll agree on that but the rest I will contest...
    yes ... most people have misconceptions.
    Here's an intro from physiological viewpoint:
    Skeletal striated muscle - Wikipedia, the free encyclopedia
    "Type I" fibers are the true slow-twitch, and are recruited mainly in the aerobic regime. Even pedaling 100 rpm, in aerobic regime, is mostly recruiting slow twitch fibers.

    Note also, the triathletes have a website and forum called "Slow Twitch Forum" ... and triathlon cycling is all about long steady TT performance! ;-)


    Quote Originally Posted by hummina shadeeba View Post
    Just as a lab hasn't shown power cranks work..none have shown they don't, as far as I can read, and there are a lot of people out there who feel they're better because of them. ...
    It is logically impossible to "prove a negative". The burden is on proponents to prove a positive benefit.

    It is equivalent to asking "Prove there's Not a little green man behind you, who disappears without a trace whenever you turn around, or try to take his picture". There's no way to prove that.

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    Id say the burden of proof is on you as you're the one saying they don't work. Just because something hasn't been proven to work doesn't mean it doesn't.

    But I'd rather you just answer my one question about if you think it's possible the study demonstrates that cyclists were pulling on the backstroke since there is little to no weigh showing up there and people are not letting their leg weight (roughly 25 pounds) weigh the pedal.
    Continuing the attempt to "prove a negative":
    prove to me they aren't pulling on the backstroke. Or maybe the fact that the weight doesn't show there is proving they are pulling. Frame it how you will.
    I didn't read the whole study though so I don't know...maybe they did prove this.

  14. #39
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    Quote Originally Posted by hummina shadeeba View Post
    ...
    But I'd rather you just answer my one question about if you think it's possible the study demonstrates that cyclists were pulling on the backstroke since there is little to no weigh showing up there and people are not letting their leg weight (roughly 25 pounds) weigh the pedal.
    Continuing the attempt to "prove a negative":
    prove to me they aren't pulling on the backstroke. Or maybe the fact that the weight doesn't show there is proving they are pulling. Frame it how you will.
    I didn't read the whole study though so I don't know...maybe they did prove this.
    Find the Coyle paper, read it, and try to understand it. I can't keep trying to "re-explain" it, as it seems semi-futile.

    The Coyle study measured torques and forces separately & independently on left & right pedals. The presence of a negative torque on the "upstroke" leg can only be interpreted as no pulling up, there is no other explanation grounded in mechanics & physics.

    And in case you're skeptical about the "mechanics & physics" involved, the basic principles have been repeatedly proven true & valid for at least the last 350 years.

  15. #40
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    I found this link. talks about both the study and the power cranks and doesn't support either of what you are saying
    PowerCranks related study - Coyle factors associated with elite performance
    it is put out by powercrank but does have a good argument as far as I can tell

    The Coyle study is over a hundred pages. I'm not going to read it. Not everyone agrees on what the Coyle study "proves" and I don't think it's fair to accept it as the end of the question. Supposedly the Coyle study goes against pretty much every other similar study done before.
    It talks about exactly what I was saying..the weight of the leg on the backstroke. I'm feeling like a genius now.
    I'll look into it some more.
    peace.

  16. #41
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    Quote Originally Posted by hummina shadeeba View Post
    I imagine someone will come out with a crank someday in the future that will enable the crank lever to keep the pedal in the ideal 3 to 6 0'clock position constantly. This will allow the rider to be in a most powerful/efficient leg angle continuously. maybe.
    Not much gain with that special crank, you are already pedalling like that. No need for a new type of crank, the most effective sector in the power stroke semi circle is between 2 - 4 o'c, here you get best torque return from the maximal force that is applied to the pedal. By a switch in technique this powerful sector effect can be doubled to extend from 11 - 4 o'c.

  17. #42
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    Like old, dead threads?
    "When man invented the bicycle he reached the peak of his attainments."
    -Elizabeth Howard West

    Never use your face as a brake pad.”
    -Jake Watson

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