What is the evidence that training with power is superior to . . .

swampy1970

No... you have me telling you that they helped me get faster. What you do with a piece of equipment and how steadfastly you stick to using it is upto you and you may not get the same results. However, from other PowerCrank users that I have been in contact with I'd say there'd be a reasonable chance that you may see improvement beyond that you were seeing already.

If you want actual lab data or downloads from a PowerTap or similar device, then feel free to pay for the above - otherwise you'll just have to deal with my own test data.

What's the mystery 'supplement' - You eatin' the same cheeseburgers that Jan (Ulrich) used too over the winter months?

Alex Simmons

it's absolutely glorious morning here in Sydney.

Just thought I'd say that

__________________
http://alex-cycle.blogspot.com/
http://www.cyclecoach.com/

RChung

Yikes. Two words: Gastric. Freezing.

swampy1970

It's mighty fine and dandy here. 80F and a light breeze. Just want to sit outside and relax.... Got another 19 minutes before I drop the top on the car and go home!

So what's this gastic freezing m'larky? And what does frozen crap have to do with anything? Is it what happens when you ignore the heart rate and press on regardless staring at the power meter thinking that 390watts is just fine.... minutes later the EMT's show up in the ambulance and see that you hit the floor with a final HR of 237bpm... then they stick you in the morgue.

swampy1970

So how 'bout those Rotor cranks....

RChung

Well, here's a study with a counter-balanced cross-over control design.

RChung

Did you try googling it up?

Fday

Isn't the theory behind the Rotor system to maximize the "pushing" muscle contribution and "minimize" those pesky dead spots? Either, it would seem, the product doesn't do those things, or "just pushing harder" isn't quite what a lot of people make it out to be.

swampy1970

Given that I had more pressing matters... no. I will though.

RChung

First, I think a more accurate description of the theory was about duty cycle, not dead spots. Second, it's pretty interesting what a well-designed study can show.

Fday

Perhaps you might be right about the "duty cycle" thing. However, I don't believe I have ever heard an advocate (even the company) use those terms. Isn't the part of the "duty cycle" that is being "emphasized is the "pushing part"? Doesn't slowing the pedal speed on the downstroke allow for a stronger "push"?

Also, wouldn't it be nice if there were some studies, let alone well designed studies, looking at training methods?

swampy1970

Yup.

So, how does the RS4X work?
Simply put, the RS4X increase your bicycle's gearing, slowing the power/downstroke while reducing the gearing and speeding the recovery/upstroke. The action is very brief, and hardly noticeable in your first 20 minutes of pedaling, fading into a normal feel within the first 30 minutes of riding. This gearing change allows for the removal of the dead point, increasing the time that you are "pushing" down on the pedals

Metabolic Efficiency of the Rotor System compared to a Conventional Bicycle in
Professional Athletes

A. Córdova, F. Navas, P. Carrasco*.
Dpto. Fisiología. E.U. Fisioterapia-SORIA.

During the execution of any exercise, as long as the work-load and time practiced is increased, lactic acid
concentration in the blood increases, which reduces the athlete's ability to perform, and also promotes muscular
fatigue. Various factors, such as the crank system or the frequency or intensity of the exercise, determine the biomechanical
and metabolic efficiency of the cyclist. The Rotor system, a crank system for bicycles, is a mechanism
made up of independent cranks that optimize kinematics through the pedal, so that each crank moves slower during
the lowering of the pedal, creating a situation where both cranks never coincide at the dead point of the pedal cycle.
As a result of this kinematics, the pair (force) that the system requires from the knees during the lowering of the
pedal (extension of the knee) is greater than during the climb (flexing of the knee), which corresponds to the knees
muscles abilities to push. In this study we propose to analyze the metabolic efficiency of the Rotor system in
comparison to the conventional crank system in professional athletes.

Eight professional athletes participated in the study (Kelme Cycling Team), each of whom gave their consent to
participate in the study after a detailed explanation of the work protocol. A maximum, incremental test was
completed with the same bicycle (placed in a cycle-simulator Cateye GS-1000), but with different crank systems
(Conventional in comparison to the Rotor). The tests were completed in two consecutive days, realizing each day
half of the racers with one system and the other half with the other system. The cyclists were monitored with a
Polar Pulse Monitor, and in different moments of the test (32, 40, 48, 54 y 62 Km/h) blood samples were obtained
via the ear lobe to measure lactic acids (YSI model 1500 Sport). The results obtained show that at the same speed,
the heart rate (3.5%) as well as the lactic acid (13.5% at the end of the test) were lower when the Rotor system was
used, with greatest differences at levels where the force applied was nearest to the anaerobic threshold of the
cyclist.
In conclusion, we believe that the Rotor system is a mechanism that improves the metabolic efficiency of the
cyclist and produces less physical wear for the same amount of work.

giannip

If you body is tired / sick and you're overdoing things as you are suggesting, you won't be able to push the 390w.

RChung

Here's what a preliminary study of the Rotor system found in 2002. Note that a change was observed in delta efficiency which is similar to the Cordova, Navas, and Carrasco study you cited. In fact, if you squint your eyes and look sideways it's sorta like what Luttrell and Potteiger found for PCs.

Sounded pretty promising, huh? However, here's what several of the same authors found two years later in 2004 when they concluded, "indicators of endurance cycling performance do not seem to be improved with the Rotor in trained cyclists."