Power/Duration Curve

Originally Posted by frenchyge

I don't think you'd be able to use that chart because the values don't represent a single rider (or group of riders) across the different time periods. IOW, Andy says that the short duration World Class figures are from the top trackies, whereas the longer duration WC figures would come from the TT specialists.

If you're looking for where you are stronger vs. weaker than the populace, then wouldn't you use Andy's system described here: http://www.cyclingpeakssoftware.com/profile.html

and compare your shape vs. the different 'rider types'?

Originally Posted by RapDaddyo

This chart suggests that as one's FT increases, the power/duration chart flattens out at the short (duration) end.

Originally Posted by asgelle

Have you looked into the Monod Critical Power model? There's a good layman's sumary at http://www.velo-fit.com/articles/critical-power.pdf The gist of it is that for times greater than about 5 minutes, the points along the power-duration curve are not independent but depend on only two parameters - critical power and anaerobic work capacity. If these two values are known, all points on the curve can be filled in.

Originally Posted by frenchyge

I have to disagree with that conclusion. You've chosen the horizontal values, but remember that that doesn't represent a single rider or group across that horizontal row. Individuals will typically have a slanted profile across the columns.

What your bar graph shows is that there's somewhat less power variation between Sprinters and TT-ers (expressed as a %of FT) amongst the better riders than there is in the less gifted riders. I'm not sure what that information could be used for, but it doesn't seem surprising.

Originally Posted by RapDaddyo

Actually, quoting Andy, "the vast majority of non-elite athletes will likely show a generally horizontal power profile."

Originally Posted by frenchyge

Don't forget the sentence that precedes your quote: "Given the fact that only specialists will likely truly excel at the extreme durations, very few individuals will show this pattern and still fall at the upper end of each range." The 4.71 and possibly 4.03 FT rows fall into that category.

Originally Posted by RapDaddyo

Just for you, frenchy, here are the horizontal power profiles from the center row in the range.

Originally Posted by RapDaddyo

IOW, is the cyclist working against two constraints in VPP -- NP=FT and the power/duration curve?

Originally Posted by asgelle

This is where I think the Monod paradigm can be useful. The way I look at it is critical power (CP) is a baseline of power that can be maintained over the entire TT. Anaerobic work content (AWC) is a stack of chips that can be spent to give a boost over CP. In the simplest model, AWC is fixed for the ride: what you start with is all you have. Then the stack can be spent at an even rate throughout the TT (constant power pacing) or spent more at some times than others (VPP). The optimization is fairly simple as it comes down to optimizing how to spend your AWC chips.

A more complicated model is where AWC is allowed to increase during periods of lower power. Then your AWC is increasing as power drops below CP and there is no fixed value for AWC. In other words during periods of low power, you're storing work to be used later and AWC for the TT depends of the total pacing of the ride. I don't know how the rate of increase of AWC corresponds to power relative to CP. I think if this were known, then deriving an optimum VPP strategy could be handled.

Originally Posted by frenchyge

That's certainly the case. The best they can do is to increase power at a point within a few km of the turnaround, and recover after the turn.