WarrenG said:
The slight difference in that cadence is relevant.
Again, no. See if you can keep up this time...
Strength, by definition, is the maximal force generating capacity of muscle, which happens to occur at zero velocity (ignoring velocities less than zero, i.e., eccentric contractions, that is). With any increase in velocity above zero, force falls off progressively, with this decline in force being essentially linear when cycling. Thus, short of performing an isometric contraction against the pedal, the best approach for quantifying one's pedaling strength is to measure force during the initial portion of this decline, and back-extrapolate to zero velocity (as I have illustrated here:
http://home.earthlink.net/~acoggan/misc/id6.html and here:
http://home.earthlink.net/~acoggan/setraining/id3.html). Even if you don't actually perform the back extrapolation, however, whether you perform such efforts in an 84" or 90" (or bigger) gear makes no difference, because for the first 25 m (~3 pedal revolutions) you're still operating very close to the Y-axis, i.e., at close to your maximal force. Indeed, to argue you otherwise, as you have repeatedly done, is equivalent to saying that your mass is greater when you stand on the end of a long vs. a short diving board.
WarrenG said:
Didn't you say it was up to half a second difference?
That was at the one lap mark, not the 25 m mark.
WarrenG said:
Let's see ALL of that data.
See Stone's paper.
WarrenG said:
The race is far longer than 25m and individuals who don't race for the national team have come up with variations of gearing and cadence to match their strength off the line, and their abilities later in the event to produce their lowest overall time in the event.
I never said that gearing didn't matter to
performance (i.e., time required to cover a set distance) in competition - only that it makes no difference when quantifying your maximal force generating capacity when pedaling. Indeed, Jim Martin's inertial load ergometer could be considered the "gold standard" by which such measurements are made, and it is equivalent to doing a standing start in only a 39x17 or thereabouts (maybe 39x19 for a big dude like you).
Back to the original question: to appreciate that power/mass is a better indicator of performance ability than absolute power even in flat events such as the kilometer, you only have to look at the data for the three World Champions (i.e., Sean Eadie, Shane Kelly, Anna Meares) in Jim's study. Their absolute peak powers when performing a maximal standing start effort were ~2500, ~2000, and ~1400 W, respectively. Based on your position that absolute power is what matters the most, you'd expect from these data that Eadie would be much faster than Kelly who would be much faster than Meares. Yet, after 15 s Eadie and Kelly are both going ~18 m/s, and Meares is hanging tough at ~17 m/s. This is explained, of course, by the fact that Eadie weighs 96 kg, Kelly weighs 87 kg, and Meares only 68 kg - this makes their peak powers in W/kg much more comparable at ~26, ~23, and ~21 W/kg, respectively. Clearly, then, the initial rate of acceleration is more closely related to power in W/kg than in W alone, as you'd expect - in fact, as
required - by the physics involved.
The fact that Kelly can compete with Eadie, and even more dramatically, that Meares can come close to Kelly (through 500 m), is further explained by their differences in CdA: 0.332 m^2 for Eadie, 0.215 m^2 for Kelly, and 0.186 m^2 for Meares. While mass is a relatively poor predictor of aerodynamic drag, it is a predictor nonetheless - thus, expressing the data in W/kg is also better than W even after the acceleration phase is past and overcoming aerodynamic drag is the major consideration. (Of course, W/CdA would be better still, but that isn't the issue at hand.)