In Reply To:
In Reply To:
As regards the PC studies (Luttrell, Dixon), there is no comparison. They all had n's greater than one, had controls, and reached statistical significance regarding what was being studied. While no study is perfect, that is what a scientific study is supposed to do.
Frank:
You didn't respond to my question in post #359 above so I thought I'd ask again.
Could you describe the controls for the Dixon study, and the hypothesis that was tested?
Could you point to the research -->prior<-- to the Luttrell study that made them think that PCs would affect efficiency? Well, regarding the prior "research" I guess there were probably three they "knew" about. First, was the work I did when I determined that a 40% power improvement claim was reasonable to make. Second, I suspect they did a little pilot study, perhaps on himself before determining what protocol he might want to use. And, third, he probably researched the internet and saw the anecdotal claims people were making regarding the product. His was the first published research study on the product.
Here is what Luttrell wrote that I feel best describes his "hypothesis" for the study. ". . . Because the PowerCranks are designed for training purposes only, it is important to investigate whether any early phase physiological adaptation might occur after utilizing this device. Therefore, the purpose of this study was to compare the effects of 6 weeks of training with PowerCranks to a control group training with normal bicycle cranks on VO2max and AT during a graded exercise test (GXT), and heart rate (HR), oxygen consumption (VO2), respiratory exchange ration (RER), and gross efficiency (GE) during a 1 hour sub-maximal ride."
The Luttrell controls: "Following the pretraining testing, the male subjects were paired in accordance to their pretraining VO2max values. The female subjects were paired together (ed, there were two). One subject of each pair was randomly placed into the control group and trained using regular bicycle cranks (normal ranks), while the other subject was placed into the experimental group and trained using PowerCranks. . . . Subjects were instructed to adhere to their normal diets thorught the training period. Subjects trained 3 dwk at an intensity that corresponded to a workload of 7-% of VO2max (19). Heart rate telemetry units were used to monitor exercise intensity every 5 minutes during training. As the subjects became better trained resistance on the ergometer was increased to maintain HR at the desired training intensity. A cadence of 80 rev-min was maintained during all training sessions. . . . Each pair of subjects was given a similar training schedule in an effort tocontrol training outside the laboratory. Weekly mileage was matched between each pair of cyclists and kept similar throught the study. Subjects completed a weekly training log of total training volume during the study."
I look forward to you comments.
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Frank,
An original Ironman and the Inventor of PowerCranks