Poor man's Powercranks? (PPC)

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I agree that we get that potential energy back, ....
Frank,
You need to brush up on your physics, we don't get any potential energy back by either pressing harder on the downstroke to raise the opposing crank or by lifting on the upstroke. In either scenario we expend energy from one leg or the other or a combination of both. The only conceivable discussion of potential energy relates to the vertical height of our feet throughout the pedal stroke but that energy differential is insignifigant compared to propelling our bikes and our mass into the wind and up hills.

Your point about sharing the load between different muscle groups has merit, but the total energy expenditure is the same unless you're actively resisting the upstroke. As to whether the slightly lower load on the downstroke resulting from actively raising the other crank is worth the effort, I'd defer to an exercise physiologist.... Like the guy who's questioning your assertions.

Or, if you accept some unweighting is optimal, how much is optimal? And, how did you reach that conclusion?
You realize this is a double edged sword?

Frank,
You need to brush up on your physics, we don't get any potential energy back by either pressing harder on the downstroke to raise the opposing crank or by lifting on the upstroke. In either scenario we expend energy from one leg or the other or a combination of both. The only conceivable discussion of potential energy relates to the vertical height of our feet throughout the pedal stroke but that energy differential is insignifigant compared to propelling our bikes and our mass into the wind and up hills.

Your point about sharing the load between different muscle groups has merit, but the total energy expenditure is the same unless you're actively resisting the upstroke. As to whether the slightly lower load on the downstroke resulting from actively raising the other crank is worth the effort, I'd defer to an exercise physiologist.... Like the guy who's questioning your assertions.


You realize this is a double edged sword?Ugh, I have brushed up on my physics, at least the physics needed to understand this. Actually, the potential energy put into the leg on the upstroke is substantial because we are talking about lifting a leg that may weigh 20 lbs 14 inches. And when we compare the forces on the down stroke we would find that it is rare that the forces on the downstroke would much exceed 50 lbs such that almost half of the force on the downstroke may be coming from recovering potential energy put into the leg during "recovery". Most people look at those forces and think it has all come from pushing. It has not but it leads to a lot of confusion. So, I disagree, the amount of energy put into the leg on the upstroke is not insignificant, it is substantial, even in ordinary cyclists who have never trained on PC's. PC's simply make one increase the amount of unweighting from 80-90% to 100%.

Frank

And, I would agree that it wouldn't make much difference where the forces came from if the power remained the same except, the whole idea is to increase the power, by invoking more muscles into the stroke and to develop increased efficiencies. You can defer to Dr. Coggan if you choose, and you will be lead down the garden path of wrongness.

Dr. Coggan has yet to explain the following except to state he believes the results to be bogus. But, what if he is wrong? Two studies, the one by Luttrell showed an increase in cycling efficiency of 10% after 6 weeks of training with PC's. What this means in terms you might understand, in these cyclists they were riding at the same power at a HR 15 beats lower than they did 6 weeks before.

Another study showed a 11% increase in max power and a 15% increase in VO2 max, also in only 6 weeks. And we are getting anecdotal reports of increases in VO2 max of up to 30% in less than a year in trained cyclists. And more studies are coming down the pike. Something has to be able to explain these results. Of course, Coggan will ascribe it to placebo, or training effect, or poor study design, or anything other than what his bias says it cannot be.

Anyhow, the studies will eventually determine the truth or not. I look forward to seeing Dr. Coggan back track.

If it only took a little concentration and practice you would think the pros would have figured out how to completely unweight a long time ago. They have not or did not, at least until PC's came along. There is a fairly extensive list of pros who have thought the PC's have added substantial benefit to their training program. Hardly believe you are better, techniquewise, than they are, but I guess it is possible.

If you have been able to get on a pair of PC's and ride them without much of a problem for an hour or so the first time, then you are doing it. If not (of if you have never tried a pair of PC's) then I think you think your "experience" is more than you think it is.Well, since there's still serious discussion as to whether the mentioned technique is even necessary, whether pros have better technique than me is of no consequence. I don't need to ride PC's for an hour because nobody races on PC's (I hope!). I sure know when I unweigh my own leg better than anyone else though :rolleyes:.

Well, since there's still serious discussion as to whether the mentioned technique is even necessary, whether pros have better technique than me is of no consequence. I don't need to ride PC's for an hour because nobody races on PC's (I hope!). I sure know when I unweigh my own leg better than anyone else though :rolleyes:.People actually do race on PC's, not many but some do and they do quite well. Because they do well, they keep doing it. Courtney Ogden had the fastest bike split at Ironman Canada last year racing on PC's. This actually has included criteriums, not just time-trials or triathlons.

Another study showed a 11% increase in max power and a 15% increase in VO2 max, also in only 6 weeks. And we are getting anecdotal reports of increases in VO2 max of up to 30% in less than a year in trained cyclists. And more studies are coming down the pike. Something has to be able to explain these results. Of course, Coggan will ascribe it to placebo, or training effect, or poor study design, or anything other than what his bias says it cannot be.

Anyhow, the studies will eventually determine the truth or not. I look forward to seeing Dr. Coggan back track.

Again, if these trained cyclists are getting increases in VO2max of 30% why aren't we seeing the world of cycling being turned upside down? a 30% increase in VO2max would take a trained average cyclist to the top of the pile (e.g., something like top 5 or 10 in the TdF). Surely, Frank, you must have sold enough of your cranks to average cyclists by now for this to occur? Or you've not sold any cranks, or your fantastical claims are pure myth....

Ric

Phoeey. I don't know very many people (in fact I know none) who statienary jog lifting the foot 14 inches off the ground and continue to do so for hours.


Why 14 inches, it's the knee that is being lifted and for me that's about 10 or 11 inches and it's the effective weight of a hinged leg that you are lifting.
From my own experience the most effective area of the unweighting technique is at the start when your leg is given that instant boost of upward force which kick starts the other leg into reflexive instant action of power application but then I am accustomed to pedaling without a dead spot area where instant takeover of power application is vital.

Again, if these trained cyclists are getting increases in VO2max of 30% why aren't we seeing the world of cycling being turned upside down? a 30% increase in VO2max would take a trained average cyclist to the top of the pile (e.g., something like top 5 or 10 in the TdF). Surely, Frank, you must have sold enough of your cranks to average cyclists by now for this to occur? Or you've not sold any cranks, or your fantastical claims are pure myth....

RicHow do you know it is not when the current world RR and Olympic Champion trains on them and all three grand tour winners last year are known or we have been told have trained on them at least some? Why would you expect that someone of lower rank would leap frog the current Olympic Champion when he takes up a training device used by the Olympic Champion? So, maybe it isn't turning the world of cycling upside down when those at the top are already using them.

Besides, winning takes more than just having a high VO2 max, otherwise they would just measure VO2 max. I don't think there has ever been shown to be a great correlation between winning and VO2 max. I would expect to see a correlation between improving and improving VO2 max though.

The data regarding PowerCranks will speak for itself once more of it becomes available. You will, of course, be free to continue to ignore it should it conflict with your current bias.

Frank

Why 14 inches, it's the knee that is being lifted and for me that's about 10 or 11 inches and it's the effective weight of a hinged leg that you are lifting.
From my own experience the most effective area of the unweighting technique is at the start when your leg is given that instant boost of upward force which kick starts the other leg into reflexive instant action of power application but then I am accustomed to pedaling without a dead spot area where instant takeover of power application is vital.You are right, it is the foot that is lifted about 14 inches (twice the length of the crank). You are right, the knee is lifted less, and the CG of the thigh is lifted even less, but that doesn't mean it doesn't take substantial energy to do so.

How do you know it is not when the current world RR and Olympic Champion trains on them and all three grand tour winners last year are known or we have been told have trained on them at least some?


we don't even know who the big Grand Tour winner is...

That said even if they did train on them, this would be proof that even if we accepted they worked (i.e., improved performance) it isn't by the magnitude you keep suggesting (30% VO2max, or 40% increase in sustainable power). That is, the difference between winning and not winning is very small, and that if they suddenly gained the 30, 40 or whatever daft % you want to come up with the margin they won by would be a huge difference to what it currently is (was).


Why would you expect that someone of lower rank would leap frog the current Olympic Champion when he takes up a training device used by the Olympic Champion? So, maybe it isn't turning the world of cycling upside down when those at the top are already using them.


VO2max is the rate limiting mechanism in endurance exercise. Considering these riders were professional prior to your supposed intervention (your cranks) they've had small changes in fitness not huge great big walloping 30/40% increases (else their VO2max would likely be >100 mL/kg/min, which is beyond current human limits).

Additionally, as it is thought that some pros undertake doping (etc) regimens which alter haematological parameters and gain < 10% and risk their livelihood (i.e., getting banned) it would make more sense for them to use the 30/40% increase from your cranks.

Of course, though, the latter doesn't happen. It's just a figment of Franks imagination and his crappy testing equipment. I suspect he sits at home or the office dreaming up daft numbers.



The data regarding PowerCranks will speak for itself once more of it becomes available. You will, of course, be free to continue to ignore it should it conflict with your current bias.

Frank

It would be more credible, perhaps, if you suggested realistic figures of improvement rather than the crack induced ones you currently come up with. If you said, here's a product that can increase your VO2max/LT/efficiency (or whatever) by 5% that number would be at least within the realms of reality (not sure i'd still believe it). 30 - 40%, you're having a laugh, do you really think we're that stupid? My feeling is that the 40% is as real as the triathlete you came up with who was going to break the Hour Record several years ago while using your wonder cranks.

In the meantime, i suggest ploughing your profits in to a rehab centre so that you can get you off the crack or whatever it is you must be smoking.

Ric

You are right, it is the foot that is lifted about 14 inches (twice the length of the crank). You are right, the knee is lifted less, and the CG of the thigh is lifted even less, but that doesn't mean it doesn't take substantial energy to do so.I'm definitely the chum(p) amongst the sharks here.

Let me re-visit my original post. Short summary is that I was wondering if I could make better use of a modest amount of workout (actually cooldown) time to work on an area of potential improvement. Seems like the camps are polarized.

How about dropping the direct performance angle? Last July-August, I experienced moderate to strong pain in my hip flexors to the point that I missed two local TT's and in an early August "A" event my power was down 10-15% from what I was capable of.

I "cured" it by using my m/b for ~ 2wks road training. Still felt lousy at first but I believe eventually the more open hip angle allowed the h/f to come around.

If nothing else, I would love to avoid THAT experience this season.

Any advice/comments? Other than riding my m/b all the time :)

Are you forgetting about Lance? :)

No, you don't - at least not unless you think it is possible to violate the laws of physics.

I'm definitely the chum(p) amongst the sharks here.

Let me re-visit my original post. Short summary is that I was wondering if I could make better use of a modest amount of workout (actually cooldown) time to work on an area of potential improvement. Seems like the camps are polarized.

How about dropping the direct performance angle? Last July-August, I experienced moderate to strong pain in my hip flexors to the point that I missed two local TT's and in an early August "A" event my power was down 10-15% from what I was capable of.

I "cured" it by using my m/b for ~ 2wks road training. Still felt lousy at first but I believe eventually the more open hip angle allowed the h/f to come around.

If nothing else, I would love to avoid THAT experience this season.

Any advice/comments? Other than riding my m/b all the time :)Of course you can improve by "mak(ing) better use of a modest amount of workout (actually cooldown) time to work on an area of potential improvement." the only question is "How much?" My guess is not much.

But, the other aspect of this is what else you said. Clearly, if one wants to perform optimally one needs to avoid injury and if one is injured, one needs to do what is necessary to heal. Anecdotal evidence strongly suggests that use of PC's help the athlete to avoid injury (by both balancing the athlete and improving form) and help rehab the injured athlete. Nice thing we offer if you are injured is our 90 day moneyback guarantee. Use them to rehab then send them back if you feel you don't need them anymore. :-)

Of course, regarding preventing injury nothing can be guaranteed just because you train with PC's. Just look at Magnus Backstedt.

Frank

we don't even know who the big Grand Tour winner is...Sure we do, unless it changes. :-)



That said even if they did train on them, this would be proof that even if we accepted they worked (i.e., improved performance) it isn't by the magnitude you keep suggesting (30% VO2max, or 40% increase in sustainable power). That is, the difference between winning and not winning is very small, and that if they suddenly gained the 30, 40 or whatever daft % you want to come up with the margin they won by would be a huge difference to what it currently is (was).


VO2max is the rate limiting mechanism in endurance exercise. Considering these riders were professional prior to your supposed intervention (your cranks) they've had small changes in fitness not huge great big walloping 30/40% increases (else their VO2max would likely be >100 mL/kg/min, which is beyond current human limits).
Why do you think I would claim that the improvement would be the same for everyone? I, of course, don't. Those who have better form already have less to gain from PC's than the average user. Those who have worse form than average have more to gain.

And, even if we did improve Bettini's VO2 max 30% it wouldn't make much difference in the race results because of the way cycling races are raced. The best rarely get into a breakaway and try to ride away from the peloton to "prove" they are stronger. They ride in the pack, saving energy, and win at the end. Cycling, except for TT, is a tactical sport.


Additionally, as it is thought that some pros undertake doping (etc) regimens which alter haematological parameters and gain < 10% and risk their livelihood (i.e., getting banned) it would make more sense for them to use the 30/40% increase from your cranks.

Of course, though, the latter doesn't happen. It's just a figment of Franks imagination and his crappy testing equipment. I suspect he sits at home or the office dreaming up daft numbers.
No, it seems you are the one sitting at home making up what you think I say.


It would be more credible, perhaps, if you suggested realistic figures of improvement rather than the crack induced ones you currently come up with. If you said, here's a product that can increase your VO2max/LT/efficiency (or whatever) by 5% that number would be at least within the realms of reality (not sure i'd still believe it). 30 - 40%, you're having a laugh, do you really think we're that stupid? My feeling is that the 40% is as real as the triathlete you came up with who was going to break the Hour Record several years ago while using your wonder cranks.

In the meantime, i suggest ploughing your profits in to a rehab centre so that you can get you off the crack or whatever it is you must be smoking.

RicI simply put out the figures I believe the data supports. You may think they are unrealistic because you are unable to think outside of the small box you have put your brain into. If the scientific data, when it is published, counters my claims I will change them. So far, the independent data I have seen support them. If you have some other data to suggest my figures are wrong please let me know.

Frank

Sure we do, unless it changes. :-)


i'm pretty sure we don't know (i'm prepared to be wrong on this though)


Why do you think I would claim that the improvement would be the same for everyone? I, of course, don't. Those who have better form already have less to gain from PC's than the average user. Those who have worse form than average have more to gain.


so, what do you claim for pros then?


And, even if we did improve Bettini's VO2 max 30% it wouldn't make much difference in the race results because of the way cycling races are raced. The best rarely get into a breakaway and try to ride away from the peloton to "prove" they are stronger. They ride in the pack, saving energy, and win at the end. Cycling, except for TT, is a tactical sport.


obviously, you have zero idea how cycle racing works then...


I simply put out the figures I believe the data supports.


you mean the utter twaddle you came up with the first time *you* used used your Power Cranks when you were on your Cateye and you saw a 40% increase in power. Amazing.


You may think they are unrealistic because you are unable to think outside of the small box you have put your brain into. If the scientific data, when it is published, counters my claims I will change them. So far, the independent data I have seen support them. If you have some other data to suggest my figures are wrong please let me know.

Frank

well, i may have a small box for my small brain, but at least i don't live in cloud cuckoo land smoking crack.

How about the fact that no average cyclist (as previously defined by you) has ever made the jump to being world class (with the gain in power you're always talking about) after using your cranks. Surely, some, with all the cranks you've sold have made these increases in power and like it or not Frank, an average racer making those increases in power would have made it to a world level. Wake me up when that happens.

Ric

so, what do you claim for pros then?
No specific claims for pro cyclists other than we will make them better. I have no data to suggest how much better they will be on average however, for most of them, any improvement will be welcome. The feedback we get from most of them is quite positive.

For pro triathletes we tend to see 15-30 minute improvements in IM bike splits (5+ hour to 4:45-4:40 bike splits) and 30 sec per mile IM run improvement within one year on average. There have been 17 pro triathletes who have won their first IM after first training on PowerCranks.

Frank

No specific claims for pro cyclists other than we will make them better. I have no data to suggest how much better they will be on average however, for most of them, any improvement will be welcome. The feedback we get from most of them is quite positive.

For pro triathletes we tend to see 15-30 minute improvements in IM bike splits (5+ hour to 4:45-4:40 bike splits) and 30 sec per mile IM run improvement within one year on average. There have been 17 pro triathletes who have won their first IM after first training on PowerCranks.

Frank
I henceforth promise to avoid trademarked terms in my thread titles ... too much rancor that I'd hoped to avoid on here.

I henceforth promise to avoid trademarked terms in my thread titles ... too much rancor that I'd hoped to avoid on here.It is not the trademarked name but the independent crank concept that is "controversial". If you had said "alternative to independent cranks" we would have had the exact same "discussion." It just turns out that there is only one brand of independent cranks, hence the "problem" with the name.

Frank

Because it gets you using more muscle mass, DUH!

<snip>

FrankOn avg. how much of an increase in muscle mass and is thee an increase in O2 consumption assosiated with this? How does the increase in wattage associate with this increased O2 consumption?

Justin

On avg. how much of an increase in muscle mass and is thee an increase in O2 consumption assosiated with this? How does the increase in wattage associate with this increased O2 consumption?

JustinI am guessing now but based upon some early study results and anecdotal reports we would have to guess that the increase in muscle mass used is substantial since increases in VO2 max are substantial. Dixon reported VO2 max increased 11% in 6 weeks. I am not sure how one would explain increasing VO2max without invoking training more muscle mass aerobically.

Some of the increase in wattage that is seen also comes about from improving efficiency (Luttrell showed an improved efficiency of about 10% also in about 6 weeks). Only when one combines the two, increased efficiency with increased muscle mass, can one can reasonably explain (although these explanations still remain unreasonable for some, many of whom are here) the very large power increases (40% or more in 6-9 months) that many report as these would be exceedingly hard to explain invoking just one mechanism.

Frank

I am guessing now but based upon some early study results and anecdotal reports we would have to guess that the increase in muscle mass used is substantial since increases in VO2 max are substantial. Dixon reported VO2 max increased 11% in 6 weeks. I am not sure how one would explain increasing VO2max without invoking training more muscle mass aerobically.

Some of the increase in wattage that is seen also comes about from improving efficiency (Luttrell showed an improved efficiency of about 10% also in about 6 weeks). Only when one combines the two, increased efficiency with increased muscle mass, can one can reasonably explain (although these explanations still remain unreasonable for some, many of whom are here) the very large power increases (40% or more in 6-9 months) that many report as these would be exceedingly hard to explain invoking just one mechanism.

Frank



Frank, for how long were you using these cranks and are you still using them.
From your own experience and all the reports you have received, can you answer this question, is the power output increase the result of having the ability to use a higher gear or a higher cadence.