Perhaps. But, then, why wasn't he seeing these improvements back in September, Ocotber, November, etc. when these rides started. He was doing them on regular cranks. This is a relative recent phenomenon.

What Tigermilk and you have done is give an explanation. That doesn't, necessarily, make it right.

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Frank,
An original Ironman and the Inventor of PowerCranks

Because I was bored and I actually had the chance to read the thread more thoroughly I thought I would clarify just a couple of things:

1. My quoted FTP of 260w at the time was based on peak fitness in '06. I'm quite certain my FTP had dropped a good 10w by the time I started training on PCs. I don't bother to change it in WKO+ during the off-season. I establish an FTP primarily for race execution purposes so I adjust it only during summer timeframe. I don't really care if I'm doing my training intervals at 90% of (true) FTP or 95% of (true) FTP -- they're always done based on my RPE anyway so they tend to vary week to week by maybe ~5% one way or the other.

2. I have a good 5+% delta between indoor and outdoor power and my FTP is based on outdoor power. Many times you guys were comparing indoor power to an outdoor FTP at peak fitness.

It just points out that we have to be careful about reading too much into the numbers in certain situations. You can easily see how things could be 10% off based on indoor vs outdoor power and/or peak fitness vs non-peak fitness.

I can say without a shred of doubt that the biggest bang for me came that year after I did a series of 6hr long rides on a very tough course yielding IFs between .77 and .81 (based on a 270w FTP). Of course, that series was all performed on regular cranks.

Thanks, Chris

Thanks for the clarifications. I think it speaks to the importance of not assuming too much about FTP levels without doing actual FTP testing. And even then the results have to be factored against training load and freshness.

BTW, doing 6 hour rides at an IF of 0.77 to 0.81 is not wimpy in the slightest!

Rik

Frank, I suggest you brush up on Monod critical power models. You'll find that power does decrease much beyond an hour from that model. Due to my high aerobic power relative to my anaerobic work capacity, my power for durations longer than 1 hour is not expected to drop much. Indeed, here are my expected critical powers for 60, 120, and 180 minutes for the last 7 years if I use the average of my top 10 performances at durations of 3, 5, 8, 10, and 15 minutes (again, I am using an average of top values rather than cherry picking):

Year, CP60, CP120, CP180
2003, 262, 260, 260
2004, 260, 258, 257
2005, 271, 269, 268
2006, 271, 270, 269
2007, 274, 272, 271
2008, 272, 270, 270
2009, 273, 272, 271

Granted Monod does breakdown for longer times, it nonetheless demonstrates my aerobic power is my strength. If I had much better AWC, there would be a bigger difference between the critical powers.

Additionally, looking back at the data from the start of PC use, here are the peak 120, 150, and 180 minute normalized powers since that time along with my all-time best prior to PC use:

Month, NP120, NP150, NP180, Comments
All-time, 265, 256, 249
August, 230, 223, 198, Started to use PC and rode mostly L2 for the month
September, 242, 240, 234, Longer "hammerfest" group ride, more L3 work during the week with PCs
October, 258, 256, 247, L3/L4 work with PCs
November, 260, 256, 249, L4 work with PCs
December, 256, 252, 245, doing some L5 work
January, 264, 256, 244
February, 257, 255, 249
March, 252, 248, 242
rest of the time - just haven't done that crunching yet, but they are enveloped by the above

As you can see, the powers during that time are enveloped by my previous bests for those durations. Given that August was essentially a month of "junk" miles (L2 stuff) and by September I was seriously starting my training year again, it's not a surprise to see an increase from August --> Sept --> Oct due to increased tempo and threshold volume. A detraining effect in August followed by rebuilding the engine. Are you surprised by that?

So what is going on here? I'm an aerobic engine by nature. Those NP120 numbers are close to what I can do for average power if rested for a few days and my fuel stores are up. Those numbers don't surprise me one bit. I honestly expect to be in that range.

The answer to #2 was in one of my posts. Yes, my teammates are seeing similar "gains" compared to last year. Just the increase in ride length accounts for higher 2-3 hour power values. Considering most of my teammates are likely aerobic engines, this is not surprising.

Now you say


Spun another way, having a higher ability at two or three hours than before would be interpreted by most as having longer, more intense, rides than previously, regardless of FTP. You can certainly increase your 2 or 3 hour power WITHOUT increasing FTP. One of those power axioms is FTP is a measure of how hard you can ride, your CTL (chronic training load) is a measure of how long you can ride hard. I'm a mileage junkie; I like to have a higher CTL. It's very old school - want to go harder longer? Ride lots...

And don't worry Frank. I won't be attributing any gains in FTP to my Saturday rides. Why? Because based on the historical data and based on mixing up my training with PCs, my FTP hasn't budged. If anything, what this year has taught me is that I should make better use of my time - train less but harder. I'll have the same fitness but have more hours in the week for stuff off the bike. Likewise, I won't blame PCs for not increasing my FTP. I'll blame that instead on genetics.

Let me get this straight. You are trying to tell me that the maximum power you can sustain for 1 hour is only two watts higher than what you can sustain for 3 hours? And, that this power hasn't varied more than a couple of watts of the last several years?

I certainly don't see that in this graph


Perhaps you could fill us in on how your reached this conclusion.

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Frank,
An original Ironman and the Inventor of PowerCranks

So, I see a 15 watt drop between NP 120 and NP 180 in your all-time bests. Tell me again how it is you only have a two watt drop between CP 60 and CP 180?

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Frank,
An original Ironman and the Inventor of PowerCranks

It doesn't surprise me they are better. It does surprise me that the only improvement they would see would be beyond 90 minutes or only in the slope of their drop off beyond 90 minutes and not increases across the board. Can you get and post their data so we can confirm?

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Frank,
An original Ironman and the Inventor of PowerCranks

Your admitted focus is the 40km TT. Why on earth would you train that way if all you expected it to do is to improve you in times beyond 90 minutes? Makes no sense to me.

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Frank,
An original Ironman and the Inventor of PowerCranks

More I read about the PC's more confused I am.
I am really curious to know how it would work for me.
A pitty it's so expensive. The price would be more accessible, the decision would be easier.
It's really hard to proove that any improvement is dedicated to the PC's ... how you can manage that scientificaly ? No way to proove it with humans because
conditions always change.
The same story with Newton shoes ... how can you quantify the improvement ? Impossible ...
Now, I am thinking to purchase a set of PC's, put it on a static bike ...

---

Disclaimer : work in bike/triathlon industry

Your analysis is correct. Almost impossible to prove anything about any product. The only thing we really do to help make your decision a little easier to try them (and to see what they might do for you) is our 90 day money back guarantee. Almost everyone is starting to see the improvement by that time if they are used regularly.

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Frank,
An original Ironman and the Inventor of PowerCranks

Frank, all I can say is

1) read up on the Monod critical power model and report back when you understand it and its limitations
2) get a powermeter, ride your bike, and understand the difference between average and normalized power
3) re-read up on critical power
4) understand that for longer durations, there are two ways to raise the curve - raise the y-intercept or increase the negative slope (make it less negative and closer to 0); if you get out and ride with power and make an earnest effort at training, you'll find that for those longer durations it's more about slope than intercept
5) re-read up on critical power
6) my yearly A-race is a 40k TT, but I do other events as well ranging from track events to 2-5 hour road races

Seriously, I think it's to the point where you should really pick up a book on bike training, pick up a power meter, and train hard for a couple of years so you can actually understand all this conversation that is whizzing around you and that you fail to grasp some of the basic concepts of. You may feel you are strong on theoretical, but honestly you need to be strong on the application to better understand what's bandied about and to better support your product.

Could you answer the question. Were you telling me (us) that your CP 180 is only 2 watts less than your CP 60? If so, how did you reach this conclusion?

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Frank,
An original Ironman and the Inventor of PowerCranks

So, I took your suggestion and tried to do a little more reading to see if I might be missing something.

I found this:
From this list from Dr. Coggan it would seem that a better estimate of what you can do is what you can routinely generate in training than critical power testing. Isn't what you can routinely do in training those graphs you did using the 20 ride analysis? I am still confused as to how you determined that your max sustainable power drops only about 2 watts going from 1 to 3 hours.

Then I found this from Training and racing using a power meter: an introduction by Andrew R. Coggan, Ph.D.
I am still confused, based on the above (and my previous understanding), how it is you are trying to explain how increasing the duration of the long "hammerfest" ride would only have an effect on your power over 90 minutes.

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Frank,
An original Ironman and the Inventor of PowerCranks

I had answered it in the original post - Granted Monod does breakdown for longer times, it nonetheless demonstrates my aerobic power is my strength. If I had much better AWC, there would be a bigger difference between the critical powers.

Now if you properly did your research you would have found this out for yourself rather than having to be spoonfed every step of the way. Yes, critical power is one of those "7 deadly sins" of estimating threshold, but it's not as "deadly" as some of the other sins. If you had taken the time to research critical power, you would have found that it's an extremely good estimate for sustainable power. Is it as good as a 1 hour TT? No. But I will tell you this, Frank. In my 7+ years of being guided in my training with a powermeter and analyzing several thousand files of my own and others, I think I have developed a rather good knack at estimating FTP based on said files. The CP60 numbers I provided are within a few percent (as in 1-2%) of what I would consider my sustainable (and repeatable) hour power when in form. Could I squeeze a few more watts out come race day with a 2- or 3-sigma performance? Perhaps, but perhaps not.

Did I ever say my max sustainable power drops only a couple of watts for 2 to 3 hour rides? No. I never did. You did. I said THE MODEL says that, and that bold text above, which I'll repeat here so there's no confusion - Granted Monod does breakdown for longer times - is what predicts that minimal drop. The presentation of my predicted CP60, CP120, and CP180 was merely to demonstrate to you how my aerobic power is a bigger contributor than my anaerobic work capacity. It should be clear that I presented my ACTUAL data for 120 and 180 minutes, and those clearly are not the same as my CP120 and CP180 predictions.

Regarding the comment from Andy about pursuiters doing a ton of aerobic work, etc. Spend the time to do the research. You'll find it's all about the ability to do work. The pursuit, desite its short length, is an aerobic event. If pursuiters only did 5 minute workouts, they'd be missing out on aerobic power development and wouldn't improve.

Now here is a nice instructional lesson on how to calculate critical power, how it predicts, how it breaks down in some situations, and also how if include longer efforts how it predicts practically no benefit for shorter durations. Let's use actual data, an average of my top 10 powers for durations of 3, 5, 8, 10, and 15 minutes. That would be 331, 317, 297, 294, and 283 W. Calculate the work (that's power*time) and plot time on the x-axis, work on the y-axis. Fit curve to that data. The equation for this line is W=270*time+214 (numbers have been rounded). Back solving for CP120 and CP180, you would find values of 272 and 271 W respectively. Now let's say I've got a super-diesel and can actually produce 272 W for 2 hours and 271 W for 3 hours. Using only those 2 data points, what would the new equation be? My math gives me W=269*time+360. So what would the predicted power be for 60 minutes? Pretty easy to figure out .... (269*60+360)/60=275 W!!! So a whopping 2 W increase! It should be noted that this increase is solely due to rounding errors. Had I used the number popping out of the original equation as inputs the 2nd go-round, CP60 would be the same, as it should as they are the same line.

Let's use my actual data. Cherry picking and using my best 2 hour NP of 265 W and 3 hour of 249 W, this leads to W=217*time+5760. This equation predicts an hour power of 313 W. Quite a difference huh? But look at that equation. That slope dropped like a rock. That slope is a measure of your aerobic power. To compsenate, my AWC has shot through the roof. Now I would love to have an AWC that high. But even going back and choosing my parents and being doped to the gills would make that sort of AWC impossible.

That simple exercise alone should easily demonstrate how increasing the length of my "hammerfest" ride would only affect longer term power. Yes the Monod model has limitations, but those limitations are more on the predictive side of longer durations (i.e., much longer than an hour). Likewise, it demonstrates that raising the right side of the power-duration curve doesn't mean an increase in shorter term powers.

I'm not the first to notice that generating higher power for longer durations has no/minimal effect on FTP. Take a look at http://www.biketechreview.com/.../stripped_down_3.htm

Perhaps your misunderstanding of power and how performance modeling is done affects some of your comments to me. I would say that I felt I was adapted to PCs, but your response was always, well, you may think you are adapted since you can ride for 3 hours, but what about 4 hours? Perhaps you interpret this additional time as being the answer to increasing FTP. I don't know. But I chuckle to myself that if I reported I did a double century on the damned things you'd say I still wasn't adapted until I did a triple. At what point does one become adapted? It seems like a moving target for you. You'll take claim of the Luttrell data and take pride in that 6 weeks of limited use. If anyone sees a gain, they are adapted. In they don't they aren't, regardless of how much time they've spent on them. You can't have it both ways.

There are a myriad of tools in our toolboxes to analyze the data. I've selected ways which I believe truthfully represent what is going on with my physiology. All my data is available for the asking, from this past year of PC use and all the way back to my very first ride on a Powertap 7 years ago. Anyone is welcome to view, critique, and spin the data as they choose fit. And most importantly, my data is guaranteed not to have gone through the "Joanquinizer."

Same. I heard of a swim coach who, at the entrance to the pool, hung a sign which said, "Don't swim half-fast."

I wonder if I could get away with that in my district.

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#cureMS

Joaquinizer beckons!

Thanks for the further explanation.

I am pretty much amazed that you presented your CP60 and CP180 data as evidence you are an aerobic engine when if comes strictly from a model that you admit breaks down at longer durations. And, then you come here and defend it by explaning the equation that you admit that breaks down. Why did you even present that data if you don't believe it to be true or if you don't believe the equation applies.

If we look at your graphs of best power vs time we should be able to come up with an equation that best fits those curves. I presume that is what Monod is trying to do, trying to predict these curves using data from short trials. But, it doesn't predict your curves very well and, what I was originally commenting on is it would appear that the equation that fit this years data is substantially different than the equation that fit the prior few years. I asked the question as to how one could explain that as it didn't make any sense to me. I would expect your entire curve to move up if you improved your aerobic fitness (accoridng to Monod?), not just one aspect.

So, you have tried to explain this by simply saying it is just that extra 30 minutes of the Hammerfest once a week. I guess that is possible but I am not so sure how you are so positive when you have made other changes to your training regimen also. So, show us the other members of the group have seen similar changes only beyond 90 minutes and, then, come up with a mechanism as to how this change only affected your abilities beyond 90 minutes? I can't do it. I know, I keep asking for those pesky mechanisms and as I have been told, exercise physiologists don't do mechanisms.

You wrote: I would say that I felt I was adapted to PCs, but your response was always, well, you may think you are adapted since you can ride for 3 hours, but what about 4 hours? Perhaps you interpret this additional time as being the answer to increasing FTP. I don't know. But I chuckle to myself that if I reported I did a double century on the damned things you'd say I still wasn't adapted until I did a triple. At what point does one become adapted?

And, why would I claim that you are not fully adapted to the PowerCranks when you feel you are. Well, lets look at the muscles and what we are trying to do. We are trying to invoke the use of more muscles into the pedaling action "equally" according to their ability. This means we need to make them equal from an aerobic stand point.

If you look at your graphs of your max power vs time for each year we see a substantial drop off starting at about 2 hours the first two years and then after that your curves have been pretty consistent. This suggests to me that it took you about 3 years to develop your aerobic capacity in those muscles and CV system.

So, along comes PowerCranks after you have several more years of training under your belt and into thse muscles and they make you use muscles fully that you had been underutilizing. My point is that I don't think it is possible to make those new muscles the aerobic equivalent of these other muscles in only a few months of part-time use when iit took you 2-3 years to achieve this level in your "pushing muscles" and you are cotinuing to use them 100% of the time. I don't doubt you are well adapted to the PowerCranks but there is no way in hell you can convince me you are fully adapted based upon your use of them.

When do you become fully adapted? Well, you are fully adapted when it makes absolutely no difference which cranks are on your bike as to what you can do on them. You are not there yet.

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Frank,
An original Ironman and the Inventor of PowerCranks

Incidentally, you do have to be careful about what data you use for calculating critical power. Recall using my "top 10 averaged" for a given year:

Year, CP60, CP120, CP180
2003, 262, 260, 260
2004, 260, 258, 257
2005, 271, 269, 268
2006, 271, 270, 269
2007, 274, 272, 271
2008, 272, 270, 270
2009, 273, 272, 271

If instead I cherry pick and use my absolute best at each duration during the year, I get

Year, 3 min, 5 min, 8 min, 10 min, 15 min, CP60
2003, 328, 312, 284, 282, 278, 267
2004, 327, 313, 288, 282, 278, 267
2005, 351, 326, 303, 297, 289, 276
2006, 339, 330, 306, 296, 292, 281
2007, 354, 348, 321, 309, 293, 280
2008, 364, 323, 302, 299, 293, 279
2009, 333, 320, 302, 301, 298, 290

So on the surface you could say (I'll play Frank for a moment), "Look, 2009 is your best year. The critical power model clearly says so as your predicted FTP is 9 W higher than any previous year." But look at the composition of that data. Notice my 3 minute power is quite low compared to the last 2 years. I just haven't gone out and drilled it for that duration this year. As an experiment, bump the 2009 3 and 5 minute #s up to 2007 levels. Know what happens? The R^2 for the fit drops from 1.0 to 0.985, the plot of work versus time has a noticeable jog to it, and my CP60 jumps to 299 W. Conversely, if I reduce my 2007 numbers a tad (given I know that my 3 and 5 minute numbers were done on a 5-6% grade on a trip to France with a fair amount of standing compared to flat land for 2009 this is a fair thing to do) the R^2 for that year goes from 0.998 to 0.997 and my CP60 goes from 280 to 287 W.

Or I could take only the data from 3 to 10 minutes for the model and leave out the 15 minute number. Doing that, my CP60 for 2007 would be 292 W and my CP60 for 2009 would be 288 W. Uh oh Frank, those PCs made me slower! But I would not leap to that conclusion (though you should given the way you seem to interpret data). It's but one way to look at data.

What this demonstrates is 1) you have to be careful which data is used for this analysis, 2) you have to understand what's behind the data, 3) you can't take what this model spits out as the be all and end all (i.e., you should use other data and methods in combination with the CP model to set your FTP).

With respect to 3) above, given the values of CP60 above for cherry picked and "averaged top 10", compare to my peak normalized power for the last several years to my averaged normalized power for the top 10 and 20 rides of each year:

Year, CP avg, CP cherry picked, NP60 max, NP60 "top 10", NP60 "top 20"
2003, 262, 267, 268, 257, 252
2004, 260, 267, 266, 261, 255
2005, 271, 276, 275, 269, 264
2006, 271, 281, 287, 269, 265
2007, 274, 280, 275, 271, 268
2008, 272, 279, 271, 263, 261
2009, 273, 290, 283, 266, 262

When you look at the set of data above, does anything really jump out at you? In my opinion, the ONLY thing that sticks out is a somewhat down year last year compared to the previous 2 years, and even then it wasn't down much. If I were truly seeing marked improvements, I would see those improvements for a variety of these measures. I have to be careful with the columns marked "CP cherry picked" and "NP60 max" knowing full well that one-off performances may have been affected by the inherent error in the measurement system (the Powertap). That 2% error associated with the PT put all those values within a few watts of each other. I see nothing in the data which suggests 40%, 30%, 20%, 10%, or even 5% improvement except for my own training from 2003-2004 and 2005 beyond.

I would say

2003 - very limited data set of only 40 or so data points; it was the year after coming off my hip fracture; learning how to effectively use power to guide my training, and even at that my 2003 data despite coming off a MAJOR surgery is within 10% of my future years; IOW, I was pretty much already "adapted" to regular cranks and already developed those push muscles
2004 - if you had all my data, you'd find that while my hour power was a little lower, it was within the same general levels (a few percent) as later years; yes my longer duration power was much lower but I wasn't specifically training that - group rides and races were typically 90-120 minutes max.
2005 onward - demands of the racing and training changed the way my rides were structured accounting for the upward shift

Don't make conclusions about me without having access to all the data.

Interesting comment you make about being fully adapted. Recall that as early as 2-3 months into my PC use I was doing tempo (L3), threshold (L4) and even a few VO2 (L5) workouts ON THE Powercranks at the SAME powers as regular cranks. So by your very own definition I was adapted. And I pushed HARD on those things man. I was pushing hard to put the damned things to the test, to put you in a positive light, and to improve my power. No I will admit that I must not be fully adapted to them since I can't get out of the saddle at the drop of a hat and sprint like mad on them. But I choose not to for safety reasons. Guilty as charged...

Now on the other hand you claim 2-3 years for me to achieve my longer duration levels for my "pushing muscles" with regular cranks. So I guess honestly users of your product should expect to be floundering for 2-3 years before seeing gains? What about all those folks in the Luttrell group? What about Joanquin? What about the Dixon study? Those were all less than 2-3 year timeframes, and 2 of those were a mere 6 weeks! I guess those riders just adapted a lot faster?

Tigermilk: You have a lot of patience to present this stuff here! Thanks for the detailed explanations.

And if it helps ameliorate your frustration, you have Frank so flustered that he is quoting Andy Coggan at you. Never thought I'd see that day!

Rik

You don't have to "play Frank" here. When you started this evaluation you were the one to chose your yearly maximum at each power as a way of evaluating improvement, not me. When you had both new maximums at both the short and long end of the spectrum (albeit by only a small amount at the short end) you decided on changing the way of evaluating to a better way. (I would agree it is a better way by the way as long as to many of the early efforts, when learning the adaption of the PC's are not included. An even better way might be to compare rides during equivalent months instead of the entire year. So, compare your top 2-3 May efforts for example. Of course, you have recently stopped using your power meter on your PC rides so not sure that is entirely fair (maybe April would be better, or do all the months and watch the changes) but it might be interesting to see.) When you changed this evaluation method it really pointed out to me your really substantial improvements this year in the endurance part of the spectrum compared to all years in the past. The questions were then asked by me, why did this occur and why is it only for periods longer than 90 minutes. Those who want to deny PC's have any usefulness, it would seem, want to attribute all of the gains to this longer Saturday ride you are doing. That is one opinion, but I haven't seen any data that would support that view.
I don't know why you are still using a model that you have admitted breaks down at the times we are discussing
I can't understand what is behind the data unless you tell me. It is why I asked how you came to these numbers.
Well, why don't you do those calculations for your 2 hr and 3 hr data (I would also be interested in seeing a 5 point average) and see if anything jumps out at you. So could you fill out these charts:
Year, CP avg, CP cherry picked, NP120 max, NP120 "top 5", NP120 "top 10", NP120 "top 20"
and
Year, CP avg, CP cherry picked, NP180 max, NP180 "top 5", NP180 "top 10", NP180 "top 20"

One other thing of interest would be to know how the top 5, 10, or 20 are distributed through the year. If in 2009 they are all in the last few months but in the earlier years they are distributed through out the year I think it would say something else.

It has always been clear that you have not seen much benefit at the times you are most interested in, less than an hour. But, it appears you have seen substantial benefits for efforts lasting 90 minutes or more. Everyone here keeps telling me that the value of a power meter is you get actual power data. Yet, here we have all this data and it is being argued, "forget the data, look at this model that I admit breaks down". Can we discuss the actual data and its significance in the area where there seems to be significant change and why this change (which seems real) is not being reflected in the shorter efforts?

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Frank,
An original Ironman and the Inventor of PowerCranks

Come on. You can't be serious. Being able to do something, tempo rides at the same power as on regular cranks, is not an indication of being fully adapted. (edit: all it shows is you have attained minimal degree of training needed to get the legs over the top that many times in that period of time, nothing about being "fully adapted". Now it is a big milestone for most users but it only represents the end of the beginning of the process not the end of the process) Take a new cyclist, he can do tempo rides for that period within the first year or two yet no one would dare suggest he has reached his full potential. Yet, you are trying to say you turned your HF's into the aerobic equivalent of your quads in three months even though you have been exercising your quads for many years. What your being able to do that in 3 months suggests to me is that there is plenty of room for improvement with further adaption if one would simply push those muscles further instead of being satisfied that they are "fully adapted" because you can do on the bicycle what they could do before. To suggest that muscles can be fully adapted in 3 months indicates a poor understanding of physiology and the training process, and a poor understanding of what the PC's are trying to do, IMHO. The whole purpose of the PC's is help the rider to push beyond where we were before, not to get back to where we were then consider the work done. Show me any data that suggests that one can achieve full aerobic adaption in skeletal muscle in 3 months and I will take it all back.

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Frank,
An original Ironman and the Inventor of PowerCranks

Here are my absolute best (i.e., enveloping) values before using PCs and the values since for the times I'm tracking for both average and normalized power:

Duration (min), Before PCs (NP), After PCs (NP), Before PCs (AP), After PCs (AP)
3, 364, 333, 364, 333
5, 348, 320, 348, 320
8, 321, 302, 321, 302
10, 316, 305, 309, 301 (NOTE NP really shouldn't be used for this duration)
15, 302, 301, 293, 298 (NOTE NP really shouldn't be used for this duration)
20, 291, 298, 290, 296
30, 291, 296, 290, 294
40, 289, 290, 287, 283
50, 288, 284, 285, 282
60, 287, 283, 284, 282
75, 273, 275, 269, 268
90, 271, 269, 261, 254
120, 265, 264, 245, 243
150, 256, 256, 230, 232
180, 249, 249, 217, 222

Should be noted that many of those PBs were in the 2007 training year. As you can see, ALL of the pre/post PC best numbers are within the error of the Powertap with the exception of the short duration (3-8 minute). Those I mentioned the bests were on a hill during a VO2 workout with some standing which tends to increase the power. I would conclude, based on the data above, that I haven't broken past any personal bests. I don't consider a couple of watts reason to jump for joy. And as you can see, my bests for 90 minutes didn't all of a sudden jump when the ride was lengthened. The "top 10" or "top 20" rides, when averaged together, did jump relative to previous years, but that's due to the larger number of samples.

To be clear: I AM NOT ATTRIBUTING ANY GAINS TO LONGER SATURDAY RIDES BECAUSE I HAVEN'T HAD ANY GAINS. What I am attributing to the longer rides is a higher overall average (when the top 10 or 20 performances are taken) due to the larger sample size. That is all. If you prefer, forget about data after 90 minutes. It neither supports nor refutes any potential benefits from Powercranks based on my data.

I would compare monthly efforts, but honestly I've shifted my season from year to year. Each year I tend to start earlier. But you can see a seasonal breakdown of 20 and 60 minute normalized power here and here (albeit the 2nd one is from December).


I'm not going to do all that right now. I would be more than happy to send out raw data to anyone who pleases. I've crunched the data in a ton of different ways and they all lead to the same thing - my performance this year is in line with past years to within the standard error of my Powertap and the expected difference between a clean and dirty drivetrain (another source of error that has to be considered).

So in a nutshell - there honestly is no significance to the 90+ minute data. I can only discuss why this change (which you think is real but actually is an artifact of the length of previous training rides) is not being reflected in shorter efforts only to a small degree. I'm a structural engineer, not an exercise physiologist. Perhaps you should get the opinion of a ex. phy. on this matter.

You know, since I wrecked last weekend I've only managed one ride - a whopping 90 W for 30 minutes. Muscles below the waist are screwed up in a big way. Wife said no bike until completely better, which may be another week. I should do a FTP test when I get back on, train exclusively on my track bike, get my FTP back to where it was and claim a fixed gear will improve your power 10-20%!

Frank said: When do you become fully adapted? Well, you are fully adapted when it makes absolutely no difference which cranks are on your bike as to what you can do on them. You are not there yet.

I said: Interesting comment you make about being fully adapted. Recall that as early as 2-3 months into my PC use I was doing tempo (L3), threshold (L4) and even a few VO2 (L5) workouts ON THE Powercranks at the SAME powers as regular cranks. So by your very own definition I was adapted.

Frank said: Come on. You can't be serious. Being able to do something, tempo rides at the same power as on regular cranks, is not an indication of being fully adapted.

Hey, just going by your definition...


Why? In actuality (and again, I'm an engineer and not an exercise physiologist (nor are you)) shouldn't hip flexors already be aerobically trained in many respects? We use our hip flexors for running, cycling (whether or not you use PCs, they contribute somewhat), walking, climbing stairs...

Now I do get a kick out of this statement from your site: But even climbing stairs in not an equivalent workout because stairs are rarely more than a foot tall, the diameter of a bicycle crank circle and it is hard to find stairs that go on forever.

Reminds me of a trip to Japan once where I was without the bike. I decided climbing the stairs would be a good subtitute workout. First day I climbed 108 flights. Second day 144 flights. I'd take them anywhere from 1 to 2 at a time (which incidentally does give a pretty close knee angle to cycling). My hip flexors weren't the problem. My legs locked up in the quads.

Now regarding finding a study - I don't have the resources for that. I don't have the background and neither do you. I'd suggest again bringing a physiologist in the debate.

And with that I'm out. It's been an interesting debate but I think all that can be said has been said. As mentioned, my data is available for anyone who wants to digest it for themselves. Frank, as I said previously, I think your product has merit as a training tool. After using them I feel there's a strong mental element to them which benefits riders. I think they can help riders break through self-imposed plateaus if they haven't pushed themselves to the limit in the past. That's a good thing.