The Dixon Study

[M Sport]

You folks are a bunch of hypocrites. You take so much on faith (power meter user anyone?)

Could you direct me to the power meter manufacturers that are claiming you will see a 40% power improvement from using their product.

 

[FrankDay]

One of the most contentious points regarding the Dixon Study has been the concept of a control group and whether or not one existed for this study. I thought that it would be easy to find the answer to this question but sadly the waters are still muddy.

One of the three authors I was able to contact responding to my question regarding the use of a control group.



To this I responded:


and his response-


Thinking the author who actually was part of the treatment group would prove to be more knowledgeable regarding that part of the study I wrote to him and asked-




Sadly I haven't received a response to the above email since it was sent on August 29th of 2014.

Frank did you know that this was a 3 part study? I don't recall that ever being mentioned. None of the 3 parts were published but it would be interesting to know more about their intent. It's too bad that Stephen Cheung was been unwilling to come forward with information. Most researches seem more than happy to share their work with others.

Hugh

So, one of the authors remembers a control group but because it isn't mentioned in the abstract he isn't sure now. So, he thinks the study should be repeated with more rigor. Heck, that should have been the thought of people not familiar with the study but interested in this area as soon as this came out. We certainly would have supported such an effort. The fact that no one has even tried says a lot to me about how biased and lazy cycling researchers really are.

So, what we have, unless you can get more information, is a study where an author remembers a control group but it isn't mentioned in the abstract but where the abstract gives a statistical probability that the PowerCranks were responsible for the increase seen. Based upon this information the Dixon study cannot be ignored out of hand. As with most studies it needs to be repeated.

Thanks for doing all this. At least we have a little more information but it clarifies little. At least it has more credibility coming from you.

One thin you might ask them is whether they remember being surprised by the result.

Edit, I do not remember anything about a 3 part study. As I said, I remembered this being designed for the participants to act as their own controls at the end of the season, when their power should be at a maximum. Perhaps, after they got the cranks they decided to rethink things and do something different. It sounds like they intended for there to be controls but because it was not in the abstract no one can prove it.

 

[Tapeworm]

I see a lot of power meters making ridiculous claims of measuring power.

Did a scan of all the major power meter sites and not one says anything about increasing power. Things like "measuring", "assessing", "recording" do get used a lot however.

These guys do however guarantee a power boost :- http://rev-electricbikekits.com.au/

 

[King Boonen]

Not even sure why this is a discussion. If it wasn't published it isn't a study.

 

[elapid]

So, what we have, unless you can get more information, is a study where an author remembers a control group but it isn't mentioned in the abstract but where the abstract gives a statistical probability that the PowerCranks were responsible for the increase seen.

No, what we have is this, as quoted from one of the authors ...

"That said, without the control group data, the findings are somewhat meaningless. We have left the abstract in a situation where we do not know whether the power cranks caused an increase, or whether this increase would have occurred to the same degree simply by using normal cranks. (my bold and underline for emphasis)

...

The way that the abstract is written leaves far too many holes (i.e. lack of control group data - how does the increase from the power crank compare to if the participants had just trained normally)." (again, my bold and underline for emphasis)

As explained in both this and the PC thread, based on the study design there is no way to discern whether the improvement was due to PCs or training effect.

Frank, I am not sure if you are deliberately twisting these results or truly have a complete lack of scientific comprehension skills, but you sure don't look good when you come to these kind of conclusions.

 

[JamesCun]

You folks are a bunch of hypocrites. You take so much on faith (power meter user anyone?) yet can't fathom anyone touting something you don't understand (and don't have the cajones to even try).

Classy!!

A computrainer won't slow me down, it is just a simple bike trainer with some computer gear. I don't care what they claim in terms of improvement and I don't believe their claims either.

A power meter has no impact on my training unless I choose to pay attention to it. I don't need a scientific study to confirm that I can get info from it. I don't need a study to know that a gps or speedometer is information that I personally find useful and interesting.

You are selling a product that claims to improve performance by changing technique and training the muscles differently. I would want to have some confidence before I'd drop 1k and 6months of training.

 

[FrankDay]

Could you direct me to the power meter manufacturers that are claiming you will see a 40% power improvement from using their product.

There isn't a single one. Of course they don't have too as their disciples make these silly claims for the device for them. There are books written about how to use them. Forums devoted to the use of the device. All this without a scintilla of evidence that the device makes a whit of difference. But, the believers don't care. Don't you think if they thought their product actually offered an advantage they would advertise it? They don't.

Don't you think the fact that we do advertise an advantage suggests we actually believe there might actually be one? Probably not. Anyhow, this has little to do with this thread. Back to Dixon, hopefully.

 

[FrankDay]

Classy!!

A computrainer won't slow me down, it is just a simple bike trainer with some computer gear. I don't care what they claim in terms of improvement and I don't believe their claims either.

A power meter has no impact on my training unless I choose to pay attention to it.

Really, what is your evidence that paying attention to your power meter has an impact on your training?

I don't need a scientific study to confirm that I can get info from it. I don't need a study to know that a gps or speedometer is information that I personally find useful and interesting.

While you may find it useful what is your evidence it is actually useful?

You are selling a product that claims to improve performance by changing technique and training the muscles differently. I would want to have some confidence before I'd drop 1k and 6months of training.

That is your choice to wait. Just as it was your choice to purchase a PM without any evidence it was going to help you.

 

[coapman]

Classy!!

A computrainer won't slow me down,

It could if you are a masher, because it has the same PC objectives.

 

[Alex Simmons/RST]

Frank using the Dixon study to support his claims, despite the fact that the study was never published, the study did not support the magnitude of the improvements claimed, and, as has been revealed by Alex, Frank getting the timing of the study completely wrong ...

Just for sake of accuracy, I didn't reveal it, simply pointed out something that was already shown in the information posted by sci-guy.

 

[FrankDay]

No, what we have is this, as quoted from one of the authors ...

"That said, without the control group data, the findings are somewhat meaningless. We have left the abstract in a situation where we do not know whether the power cranks caused an increase, or whether this increase would have occurred to the same degree simply by using normal cranks. (my bold and underline for emphasis)

Ugh, this researcher actually remembered that there was a control group

I believe the control group performed the same training as the power crank group, only with fixed cranks rather than power cranks...
I am 90% sure that we had a control group, but it is possible that I am thinking of another portion of the study. You are right though, it isn't reported.

but because it isn't mentioned in the abstract he agrees that it is not possible to draw much from this.

Anyone who says Dixon can be completely discounted because there isn't a control group mentioned in the abstract is simply ignoring the fact that one of the authors is almost certain that there was one but because it isn't mentioned in the abstract that 10 years after the fact he is not going to commit to anything in this regard since he simply has forgotten a lot of the facts of this study. We have Sciguy to thank for this new information. Take your complaints to him.

 

[Alex Simmons/RST]

Frank, I am not sure if you are deliberately twisting these results

I am and he is.

or truly have a complete lack of scientific comprehension skills, but you sure don't look good when you come to these kind of conclusions.

this too.

It's really an AND, not an OR.

 

[Alex Simmons/RST]

There isn't a single one. Of course they don't have too as their disciples make these silly claims for the device for them. There are books written about how to use them. Forums devoted to the use of the device. All this without a scintilla of evidence that the device makes a whit of difference. But, the believers don't care. Don't you think if they thought their product actually offered an advantage they would advertise it? They don't.

Don't you think the fact that we do advertise an advantage suggests we actually believe there might actually be one? Probably not.

Putting aside this being the next in a series of Frank Day red herrings designed to deflect attention away from your bogus claims about PCs, time and again you have been shown ways in which performance has been improved with the aid of power meters and intelligent use of power meter data.

There is little point in pursuing this line of discussion though because:
- it's irrelevant to this thread
- you completely fail to recall every other time this nonsense argument is debunked
- there are other threads already devoted to dealing with these nonsense arguments of yours

Anyhow, this has little to do with this thread. Back to Dixon, hopefully.

So why, like Computrainer claims, bring it up?

Yes, let's get back to Dixon study, and why it does not support your claims, and why you continue to misrepresent it otherwise.

 

[FrankDay]

Putting aside this being the next in a series of Frank Day red herrings designed to deflect attention away from your bogus claims about PCs, time and again you have been shown ways in which performance has been improved with the aid of power meters and intelligent use of power meter data.

All I have asked for is scientific support of that contention. It simply doesn't exist. That is what you demand of me to make any claims for my product.

...

Yes, let's get back to Dixon study, and why it does not support your claims, and why you continue to misrepresent it otherwise.

Yes, let's get back to the Dixon study. Maybe Sciguy can ferret out a little more data. Right now we have learned there is a 90% chance of there being a control group that was simply neglected to have been mentioned in the abstract. If there was a control group this study definitely supports my claims because the study lasted 6 weeks and my claims require 6-9 months to achieve. Take your complaints to Sciguy, he was the one to ferret out this latest data.

 

[King Boonen]

Sorry, this is all utter junk. This is not a study. It was never published. It is utterly meaningless. Anyone using this study as proof of anything is just trolling. This should be very obvious to anyone.

 

[CoachFergie]

Not sure why people engage Frank in discussion. Report him when he spams or trolls on the forums.

 

[elapid]

Ugh, this researcher actually remembered that there was a control group but because it isn't mentioned in the abstract he agrees that it is not possible to draw much from this.

Anyone who says Dixon can be completely discounted because there isn't a control group mentioned in the abstract is simply ignoring the fact that one of the authors is almost certain that there was one but because it isn't mentioned in the abstract that 10 years after the fact he is not going to commit to anything in this regard since he simply has forgotten a lot of the facts of this study. We have Sciguy to thank for this new information. Take your complaints to him.

Frank, we are talking about the Dixon study. The published abstract does not include the magic control group and the author does not remember the results of the control group, so the control group is a mute point and irrelevant to this discussion until further information comes to light. So we are left discussing what was published and that was the group before and after PCs from which no conclusions can be made because we do not know if this was training effect (especially as we now know that this study was conducted at the start of the season rather than the end of the season as you wanted us to believe) or PCs. But you know that already and are just doing a very good job of playing dumb.

 

[JamesCun]

It could if you are a masher, because it has the same PC objectives.

What?? A computrainer is an electronically braked indoor training tool. Spin scan is only one part, and a rarely used feature in my experience.

 

[sittingbison]

Gentle(wo)men, listen up.

Enough is enough. Trollkraft on this thread is beyond redunculous. Continue and you're out of here.

Everyone else, try and refrain from resorting to personal attack, report suspect posts instead please

Cheers
Bison

 

[coapman]

What?? A computrainer is an electronically braked indoor training tool. Spin scan is only one part, and a rarely used feature in my experience.

Same PC pedalling objective which is to distribute power application as evenly as possible around the pedalling circle.
" The multicolor torque graph represents one full 360 revolution divided into 15 segments. The left /right leg percentage power splits give you the feedback needed to pedal in “circles”. It will identify “flat” or “dead” spots in the pedal stoke where optimal power is not transferred to the drive train."

 

[JamesCun]

Yes, let's get back to the Dixon study. Maybe Sciguy can ferret out a little more data. Right now we have learned there is a 90% chance of there being a control group that was simply neglected to have been mentioned in the abstract. If there was a control group this study definitely supports my claims because the study lasted 6 weeks and my claims require 6-9 months to achieve. Take your complaints to Sciguy, he was the one to ferret out this latest data.

The researchers are saying they can't say for sure if there was a control group. The data wasn't reported in the abstract, which is a huge omission. Just from that info alone, the study should be completely discounted as offering any evidence of the impact of powercranks. In this sort of study, no control group data means no useful data.

 

[JamesCun]

Same PC pedalling objective which is to distribute power application as evenly as possible around the pedalling circle.
" The multicolor torque graph represents one full 360 revolution divided into 15 segments. The left /right leg percentage power splits give you the feedback needed to pedal in “circles”. It will identify “flat” or “dead” spots in the pedal stoke where optimal power is not transferred to the drive train."

This is mostly off topic, but I guess there is something to say for the difference in products between an indoor trainer and a technique correction device.

A computrainer has numerous benefits and uses. Spin scan is one possible use, although I have never used it in 10years of CT use. A computrainer is simply a training tool that adds a few features to a standard indoor trainer. It doesn't need scientific proof to be a useful tool. If you need to bike indoors, it accomplishes that task brilliantly. If you want some intense power based workouts, it helps regulate those. I personally like erg video with it, since it breaks up the boredom.

So, when you talk about spin scan, be specific. Computrainers work perfectly well if you never view the spin scan.

 

[FrankDay]

The researchers are saying they can't say for sure if there was a control group. The data wasn't reported in the abstract, which is a huge omission. Just from that info alone, the study should be completely discounted as offering any evidence of the impact of powercranks. In this sort of study, no control group data means no useful data.

As I read what sciguy has transmitted to us of his quest to find out more information re Dixon ONE researcher was quite confident there was a control group until it was pointed out to him that the control group was not mentioned in the abstract at which point he reduced his confidence to 90% regarding the existence of that control group. Still pretty confident in my estimation 10 years after the fact from not one of the primary authors. These researchers from two major universities, would hardly design a study neglecting to have some sort of control if they intended to do a statistical analysis. Neglecting to mention a control group in the abstract in view of this additional information hardly qualifies to suggest the study deserves to be completely discounted. (Nor does the fact it wasn't actually published a good reason to ignore it as someone earlier suggested.)

In my opinion this new information, that there was almost certainly a traditional control group, makes the findings showing a statistically significant power and VO2max enhancement from 6 weeks, 8 hours/wk, immersion PowerCranks training more powerful, not less. Further, those statistics had to be calculated against some sort of control group to reach the conclusion they did. All that is really not known here is the specifics. All you naysayers have to go on is you think an inexperience researcher failed to mention a control group in his abstract and was missed by his mentors has some major significance. I guess we all (or at least I) have sciguy to thank for his efforts.

 

[FrankDay]

This is mostly off topic, but I guess there is something to say for the difference in products between an indoor trainer and a technique correction device.

A computrainer has numerous benefits and uses. Spin scan is one possible use, although I have never used it in 10years of CT use. A computrainer is simply a training tool that adds a few features to a standard indoor trainer. It doesn't need scientific proof to be a useful tool. If you need to bike indoors, it accomplishes that task brilliantly. If you want some intense power based workouts, it helps regulate those. I personally like erg video with it, since it breaks up the boredom.

So, when you talk about spin scan, be specific. Computrainers work perfectly well if you never view the spin scan.

no training tool (or anything else) needs scientific proof to be useful. All scientific proof does is demonstrate the tool is actually useful (or not) as opposed to users simply believing it useful (or non-users believing it not useful). I am not aware of a single training tool used by cyclists (trainers, power meters, Spinscan, PowerCranks, coaches, weights, etc) that has been proven effective to make cyclists better than what they can do on their own. Lack of proof is not proof of lack of effectiveness. Of the items on that list PowerCranks is at least one tool that has a few studies showing some effectiveness. What hasn't been proven is the "claim" but to do that someone actually has to try.

 

[sciguy]

As I read what sciguy has transmitted to us of his quest to find out more information re Dixon ONE researcher was quite confident there was a control group until it was pointed out to him that the control group was not mentioned in the abstract at which point he reduced his confidence to 90% regarding the existence of that control group.

Frank,

1. Let's be clear on this. He was 90% certain that there was a control group for one of the 3 parts of the study. That's a good deal different than 90% certain that there was one for this part of the study.

Hi Hugh,

This was a three part study that worked off of Mr. Dixon's training group (he was the coach of this recreational cycling group). I am 90% sure that we had a control group, but it is possible that I am thinking of another portion of the study.

2.The particular author quoted was working on a different component of the study.

(my component was the central nervous system drive pre to post fatigue, less to do with the actual training)

Leaving him less in the loop regarding what was or wasn't done in regards to the training group.

Hugh