In Reply To:
i would stand by that conclusion. this is why:
i do understand that the length-tension relationship at the sarcomeric level is "somewhat" digital.
but you still won't get a curve
that digital (fig. 2) when you put a guy on a bike with those cranks. as you know very well, it is not just one muscle at one length pushing those pedals around. it is a very complex system of many muscles, many joints, and many attachment points.
nor do i claim that the actual curve will be eggshell-smooth. but it will
not be a line, it will be curved. and there willl a peak somewhere on the curve.
Or so you
predict - but keep in mind that 1) the
degree of curvature is really the issue, and 2) Jim also hasn't found any effect of crank length ranging from 145-195 mm on maximal neuromuscular power*, which would be equally influenced by changes, or lack thereof, in the sarcomeric length-tension and/or joint angle-force relationships. Finally, we also know that it takes rather large changes in saddle height (which also impacts muscle excursion) to impact either efficiency or maximal power. Taken together, what these data clearly demonstrate is that the man-machine interface isn't
nearly as critical as what most non-scientists like to believe.
*Maximal neuromuscular power was lower when using cranks that were 120 or 220 mm in length.