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  1. #1
    base training heretic Squint's Avatar
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    What's wrong with this PowerTap file?

    http://anonymous.coward.free.fr/watt...26_10_2007.csv

    Remember this article entitled, "PowerCranks: More Proof From the Real World?":

    http://pezcyclingnews.com/default.as...lstory&id=4906

    This is the PT file from that fellow that was offered as evidence to support the claims in that article.

  2. #2
    Cat WTF
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    The 1:48 of coasting?

  3. #3
    Senior Member
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    the fact he did this after 6 hours of riding?

  4. #4
    Compressed
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    Squint you may as well add the slowtwitch link to the original thread. http://forum.slowtwitch.com/Slowtwit...ertap_P1542446

    More drama in the powercranks files.

  5. #5
    Quarq shill cslone's Avatar
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    It's been determined that the guy is full of it by the Slowtwitchers?
    FS: Fuji SL1 frameset, 55.5cm toptube, excellent condition.

  6. #6
    Compressed
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    Quote Originally Posted by cslone View Post
    It's been determined that the guy is full of it by the Slowtwitchers?

    pretty much yeah.

  7. #7
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    Oh Jesus what a crock. I rode up that climb with Joaquin and I can assure you he's not full of ****. I don't know if the PCs are responsible for his power output and could really care less, but the guy is a powerful cyclist.
    Kendall Frederick

    Orange Park, FL

  8. #8
    Quarq shill cslone's Avatar
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    Okay he, Frank Day, or Pez is full of it. He has never, that I have seen, put up a graph to show these claims.

    VO2 Max. 5794 ml/min
    VO2 Max rel. 85,46 ml/min/kg
    Max Power 451 Watts at 181 bpm_
    FTP (1 hour): 394 Watts at 169 bpm at 87% of VO2 Max

    The time he rode with you, he did 358 AP at 180HR? I have no doubt that he is a strong cyclist or a hell of a nice guy, but the climb with you, and another set of race numbers he(or Frank) posted just don't add up to his claims.
    FS: Fuji SL1 frameset, 55.5cm toptube, excellent condition.

  9. #9
    Compressed
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    Kendall, I agree that it's pretty ridiculous, actually it's sad. Sad that so many people are looking to discredit anything Powercranks. Of course if Frank Day would chill on his marketing claims and endless defense of his invention then people might just let them fade to obscurity or alternatively become known as a good tool after a reasonable amount of time of letting the free market and science determine their worth.

    I feel like I have to make an admission of sinning or similar by admitting that I, yes I Compressed ride Powercranks. I rode them from late October to the beginning of March last year and I think they helped me. I can't quantify how with any significant data and my threshold certainly did not increase 40% as Day claims (I wish) but I think they helped. At the very least they've increased my mental toughness by leaps and bounds which has helped me endure some pretty rough training loads and racing. I'm once again riding them this off season and was able to pick them up right away and do some decent rides. Every ride even the easy ones with avg. power <170 have periods of agony but I'm getting better on them and have been able to do some decent L3 work. I do worry that I will be unable to give myself enough training stress with them but the school of HTFU makes me put my nose to the grind stone and attempt to do the work.

    One of the tough things is that riding PC's is like taking several steps back in ability and constitutes a leap of faith. This is difficult and can be a blow to confidence, a long term outlook is definitely required. If nothing else PC's have really helped me to dial my saddle position.

  10. #10
    Quarq shill cslone's Avatar
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    I'm not attacking PC's. It's the fact that someone lied and Frank jumped all over it saying it was because of PC's.
    It's fine if you ride them. I ride Q-rings, which after testing gained me about 8-10 watts. The part that is sad is that Frank And Joachin have been proven wrong on numerous occasions and they keep coming up with "Well, maybe this happened".... If they work for you, wether physioligically or mentally, then they work. But you aren't making claims all over the internet then backtracking when someone calls you out either.

    It's pretty obvious that Joachin has lost pretty much all credibility to those in the know.
    Last edited by cslone; 11-21-07 at 11:34 AM.
    FS: Fuji SL1 frameset, 55.5cm toptube, excellent condition.

  11. #11
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    It's looks like someone dug themselves a hole and just got deeper and deeper until the sides caved in.

    The data definitely looks manipulated.

    The arguments posted by the people who appear to represent PC's interests change from fact based (wattage, time, % grade, etc) to subjective/emotional things ("he's a father of three and a strong rider so lay off of him" sort of statements). I learned the hard way that when people run out of things which support their position in a logical way, they might try and bring emotion into the arena. Then it gets ugly because if one side no longer supports logic, there's no more constructive discussion.

    I saw a guy using PCs and asked him about it (we rode together for about 5 minutes). He'd just gotten them. I think that at some level they probably help - it's like riding one legged with both legs at the same time. I went back home, looked them up (the Pez article came up), figured out what the heck I was looking at, made my "one legged" thought, got on the trainer, and rode one legged for a bit - and yes, my legs were more tired than normal. I also remembered the first time I did one legged efforts on a trainer, and how awkward it felt. After 25 winters of very occasionally doing one legged efforts, they seem pretty straightforward to me and I can ride like that pretty hard on rollers. I decided at that point not to buy the cranks unless I learned more about them.

    Some ideas that pop into my head.
    1. If you suddenly change the workout, the athlete perceives/measures significant gain. For example, if you did one type of curl and then went and did another type, initially the new type would be stressful and difficult. The perception - "I'm getting a better workout". Once the body adapts, no more perception of a "better workout". Introduction of any new workout will result in a steep learning/growing/strengthening curve followed by the normal plateau.

    2. Correlations between equipment change and results are not necessarily causal relationships. One could say that since there is more crime in an area with more churches, churches cause crime. The former is a correlation (more churches: more crime). The latter is a (probably) incorrect causal relationship. A more realistic explanation would be "more people = more churches, more people = more crime, therefore more people=more crime. Churches aren't part of the equation. On bikes - just because I got longer or shorter cranks (I'm wrestling with this idea/theory right now), it doesn't mean that the cranks made the difference - it might be that I'm recruiting relatively new and unused muscles. Once they develop to their plateau strength, I may find different length cranks to be of no advantage.

    3. Cognitive dissonance - I am a victim of this I think but it's okay, as long as I believe it, it's real. If someone does something significant and may or may not see a return, they rationalize the chain of events. I paid a lot of money for a new bike. I went for a ride - it felt lighter, stiffer, and more efficient. Is that an accurate perception? Maybe, maybe not. I see empirical evidence saying it's probably true but I can't measure it myself. However, I'd have been really dumb to buy a new bike and not see any difference in performance. Therefore, to protect my psyche, I believe my new bike is better than my old one.

    not an owner of PCs but man have I bought a lot of gear over the years,
    cdr
    "...during the Lance years, being fit became the No. 1 thing. Totally the only thing. It’s a big part of what we do, but fitness is not the only thing. There’s skills, there’s tactics … there’s all kinds of stuff..." Tim Johnson

  12. #12
    Slow'n'Aero DrWJODonnell's Avatar
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    I agree that that data is manipulated. Zoom in on "power tap 1" and look at not only the power, but the heart rate, cadence and speed. They are too even, "even" for rollers. Plus, the changes in speed do not correspond with changes in power and or cadence (due to shifting), but there is no way anyone could argue that that part was done outside. The regularity of the heart rate repeats suggests data manipulation.

    That is what is wrong with it.

  13. #13
    base training heretic Squint's Avatar
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    Yeah, what's amusing is seeing the obvious repeating segments. They don't just look the same but are exactly the same numbers.

  14. #14
    Burning Matches. ElJamoquio's Avatar
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    Amateur data manipulators.

    Now *I* am a professional data manipulator.
    Reacting is mind candy; it requires no thought. Thinking is tedious.

    Bikeforums 'Group Buy': Kinlin Rims, Sapim/DT Spokes, Formula/Bitex Hubs


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  15. #15
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    I'll take back my earlier post, at least in regards to the PT data. I hadn't gotten a chance to examine the file earlier today. I've done so now and the data's bogus. Unfortunate, and I made a post in the ST thread saying the same.

    FWIW, I don't ride PCs and don't like Frank's endless shilling on the subject. I just felt bad for Joaquin because he got jumped on so hard in the original ST thread by people who have a bone to pick with Frank. Joaguin's a nice guy and a very strong rider; I just feel stupid getting sucked in with this obviously bogus file.
    Kendall Frederick

    Orange Park, FL

  16. #16
    Quarq shill cslone's Avatar
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    Quote Originally Posted by KendallF View Post
    I'll take back my earlier post, at least in regards to the PT data. I hadn't gotten a chance to examine the file earlier today. I've done so now and the data's bogus. Unfortunate, and I made a post in the ST thread saying the same.

    FWIW, I don't ride PCs and don't like Frank's endless shilling on the subject. I just felt bad for Joaquin because he got jumped on so hard in the original ST thread by people who have a bone to pick with Frank. Joaguin's a nice guy and a very strong rider; I just feel stupid getting sucked in with this obviously bogus file.
    KF, like was said here and on ST. It happens, and you were not intended to be a "target". Unfortunately you just happened to ride with one of the most blasted riders on any forums I read. No worries.
    FS: Fuji SL1 frameset, 55.5cm toptube, excellent condition.

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