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  1. #1
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    Coggan, FTP, and Normalized/Average Power

    It is time to update my ftp data. My last ftp (Feb) was done on a trainer where it is easy to generate a pretty flat power output (average power and nomalized power being roughly the same). I'd like to now do it outdoors 'in the real world'. But around here pretty much everything is one continuous roller. There are certainly no long climbs and (for the most part) pretty much no long flats either (15 to 45 seconds up, less than that down, repeat till done).

    Coggan's 20 minute ftp methodology uses (everywhere that I recall seeing it) average power. But I am guessing that even with my most carefully selected route and attempt to maintain a flat effort, my normalized power in this 20 minute test is probably going to be 10 to 15% higher than my average power. So I am wondering if using NP isn't a better way to establish ftp, particularly since one of my primary interests in this number is for TSS calculations (which will use NP and not average power).

    I was interested in other folk's thoughts regarding this.

    Thanks.

    dave

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    I feel that the trainer is the best place to do an FTP test for all the reasons you gave.

    I also know very little about it, so I've always done the test as prescribed, and used the conventional method for the calculations afterward.

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    If you truly push as hard as you can for 20 minutes on slight rollers and change gears to keep the power up on the downhill portion of the rollers, there won't be anywhere near a 10-15% difference. I live in the foothills of NC so our rollers probably have a little more up and down to them that what you have. I just pick the flattest road I can find and make sure to be steady with the power by shifting gears - I don't attack the upside of the roller and don't let up on the downside. If you try you'll be surprised how steady you can be.

    Believe it or not but my normalized has exactly equaled my average on a few 20 minute tests.

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    Quote Originally Posted by RShantz View Post
    If you truly push as hard as you can for 20 minutes on slight rollers and change gears to keep the power up on the downhill portion of the rollers, there won't be anywhere near a 10-15% difference. I live in the foothills of NC so our rollers probably have a little more up and down to them that what you have. I just pick the flattest road I can find and make sure to be steady with the power by shifting gears - I don't attack the upside of the roller and don't let up on the downside. If you try you'll be surprised how steady you can be.

    Believe it or not but my normalized has exactly equaled my average on a few 20 minute tests.
    Interesting that you should mention this. Today I did not set out to do a formal 'Coggan 20 min ftp thing', but I did set out to do a hard ride for a while and see how well I could regulate my power output. I was surprised in that my average power and NP were only 10W different. That surprised me (and I could probably do better than that by a bit).

    dave

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    Quote Originally Posted by DaveLeeNC View Post
    Coggan's 20 minute ftp methodology uses (everywhere that I recall seeing it) average power. But I am guessing that even with my most carefully selected route and attempt to maintain a flat effort, my normalized power in this 20 minute test is probably going to be 10 to 15% higher than my average power. So I am wondering if using NP isn't a better way to establish ftp, particularly since one of my primary interests in this number is for TSS calculations (which will use NP and not average power).

    I was interested in other folk's thoughts regarding this.

    Thanks.

    dave
    The most important person's thoughts on this would be Coggan's. He doesn't recommend any "20 minute" test. That's a rule of thumb that was proposed by Hunter Allen, not Andy Coggan. Here is what Andy's recommendations are -- note that they're listed in order from least reliable to most, and that a 20 minute test isn't on this list:
    Alex's Cycle Blog: The seven deadly sins

    Andy's "best" estimator of FTP is the average power over a hard 1 hr TT. Note that #4 is NP over an hour.

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    Lactate meters are now cheap compared to 2004 when that was written and when combined with a Power Meter and HRM, an indoor trainer protocol can easily determine the maximum power output achievable over 1 hour irrespective of the label one wishes to apply to this attribute of fitness. Assumes a very powerful fan to keep the rider cool.

    It is much easier for me than doing any testing on the road but YMMV unless it is a very long, steady climb.

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    Andy certainly had access to and experience with lactate measurements when he came up with FTP, no matter the cost. The idea underlying FTP is that it's not pegged to a biochemical measurement like blood values -- it's a practical "functional" test. You go out and see what power you can sustain for an hour. You don't need either a lactate meter or a HRM for this.

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    Not my point. The meters are available to Joe Public now. I can maintain 4.6 mmol at a certain power whereas others might be lower or higher. For me, I get much better data indoors on a trainer. I get power, lactate, and HR data and can easily control load. No so on the road.

    Few riders have the discipline to ride an hour hard outdoors even if they have a road to do it on.

    FTP is just a term.

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    Right, not your point -- the point I was addressing was the OP's. He was asking about FTP. You're talking about something different.

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    Quote Originally Posted by RChung View Post
    The most important person's thoughts on this would be Coggan's. He doesn't recommend any "20 minute" test. That's a rule of thumb that was proposed by Hunter Allen, not Andy Coggan. Here is what Andy's recommendations are -- note that they're listed in order from least reliable to most, and that a 20 minute test isn't on this list:
    Alex's Cycle Blog: The seven deadly sins

    Andy's "best" estimator of FTP is the average power over a hard 1 hr TT. Note that #4 is NP over an hour.
    Thanks for the link to Alex's blogsite. It is a useful resource that I had not encountered.

    While I was using "Coggan's 20 minute ftp methodology" as a reference to what is described in his (and H. Allen's) book, I think that you should read #6 in the link above more carefully. I would judge that the '20 minute method in the Coggan/Allen book' and that described in #6 (2nd best) in the link in your post are (outdoors, anyway) the same thing (except that the book is more specific than the description in #6 ).

    dave

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    Andy gets asked about the "20 minute" protocol (or Friel's 8 minute protocol) a lot. He has consistently pointed to his "7 deadly sins" as his view on estimating FTP, and that Hunter's "95% of 20 minute power" is a rule of thumb -- but for someone with big fingers.

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    Quote Originally Posted by RChung View Post
    Andy gets asked about the "20 minute" protocol (or Friel's 8 minute protocol) a lot. He has consistently pointed to his "7 deadly sins" as his view on estimating FTP, and that Hunter's "95% of 20 minute power" is a rule of thumb -- but for someone with big fingers.
    So what does Coggan think is a good "critical power test"?

    I mean, he says in "seven deadly sins" that critical power testing and analysis is one of the best ways to estimate FTP (top 3, in fact), and that the average power and duration results from CP tests get dumped into a CP Model.

    Just curious if Coggan has more a problem with the "95% of 20min" rule than he does with using the average power of a 20 min test in his CP Model (if it's even his; I dunno).
    Chaad--'95 DeKerf Team SL, '02 Lemond Buenos Aires, '05 Novara Buzz, '73 Schwinn Collegiate, '06 Mountain Cycle Rumble, '09 Dahon Mariner D7, '12 Mercier Nano, '12 Breezer Venturi

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    Quote Originally Posted by chaadster View Post
    So what does Coggan think is a good "critical power test"?

    I mean, he says in "seven deadly sins" that critical power testing and analysis is one of the best ways to estimate FTP (top 3, in fact), and that the average power and duration results from CP tests get dumped into a CP Model.

    Just curious if Coggan has more a problem with the "95% of 20min" rule than he does with using the average power of a 20 min test in his CP Model (if it's even his; I dunno).
    CP is Monod's idea; FTP is Andy's. In order to get robust estimates of CP you need to really work to exhaust all of your W' (since Monod's model only has two parameters, a poor estimate of W' will affect the estimate of CP). So I think Andy said that *if* you do CP estimation, you should do specific efforts in order to exhaust W' -- don't cherry-pick from your MMP curve.

    OTOH, I find that my MMP is responsive enough that I can generally spot changes in my CP even if the absolute level may be off. So I haven't done the "gold standard" one hour TT in a pretty long time, and instead I do cherry-pick from my MMP. I'm certain he wouldn't endorse what I do.

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    Quote Originally Posted by RChung View Post
    CP is Monod's idea; FTP is Andy's. In order to get robust estimates of CP you need to really work to exhaust all of your W' (since Monod's model only has two parameters, a poor estimate of W' will affect the estimate of CP). So I think Andy said that *if* you do CP estimation, you should do specific efforts in order to exhaust W' -- don't cherry-pick from your MMP curve.

    OTOH, I find that my MMP is responsive enough that I can generally spot changes in my CP even if the absolute level may be off. So I haven't done the "gold standard" one hour TT in a pretty long time, and instead I do cherry-pick from my MMP. I'm certain he wouldn't endorse what I do.
    MMP being what? And W'?

    I guess what I was asking for was more specificity as to what those "specific efforts to exhaust W'" would be according to Coggan *if* a 20 in effort is inherently problematic? Or, is it that a 20min effort is not per se problematic, and rather the simple "95% of 20min average power" calculation for estimating FTP that Coggan has trouble with?

    I mean, do you think Coggan would have a problem if you did 4 stand-alone, max effort 20min efforts over the course of a month and "cherry picked" the two best to plug into [Monod's] Critical Power model? If so, which specific efforts would Coggan prefer to see used in the Critical Power model in order to earn the accuracy suggested by his placement of "critical power testing and analysis" as a top 3 means of estimating FTP?
    Chaad--'95 DeKerf Team SL, '02 Lemond Buenos Aires, '05 Novara Buzz, '73 Schwinn Collegiate, '06 Mountain Cycle Rumble, '09 Dahon Mariner D7, '12 Mercier Nano, '12 Breezer Venturi

  15. #15
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    Ah. MMP is Max Mean Power over different durations. W' is what people used to call AWC, or anaerobic work capacity. Monod's model is that Work (in joules) = W' + CP * t where t is in seconds. There are two unknowns in that equation (W' and CP) so you'll need at least two equations. You can't plug your two best 20 min efforts into Monod's model. Instead you do (at least) two tests of differing length (say, something in the 4 to 8 minute range, and something in the 15 to 25 minute range) where you work really, really hard so that you exhaust yourself in each test. Don't do these two tests in the same day. They're supposed to be to exhaustion. Convert your watts to joules and find W' and CP.

    Coggan would say that "95% of 20 minute max power" is a rule of thumb but that the thumb is actually pretty big so FTP can be anywhere from less than 90% to the upper 90's of 20 minute max. In addition, as you become more used to the protocol you can "learn" to test so that's an added source of variability (that is, even for any single individual FTP can vary over time as a proportion of 20 minute power).

    As a not-so-aside, Golden Cheetah does the CP and W' calculations for you based on your MMP. This is the cherry-picking that Andy objects to, and he says that the CP you get from that overstates FTP. I don't really care all that much so I use Golden Cheetah's CP, with the expectation that it will do that. Basically, Golden Cheetah's CP is my rule of thumb -- but I'm aware of it. If I ever really needed a better estimate of my threshold power I'd probably bite the bullet and do a dedicated test.

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