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ROUVY - 60kg | VT1 test

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I have only recently learned a different method of modeling the power-duration curve. Traditionally, power is expressed as a function of time and the hyperbolic relationship between work rate and time has been known for ~100 years, since AV Hill plotted speed against time for swimming and running world records in 1925. The asymptote of the power-duration curve describes critical power (CP), which is considered the most robust threshold separating sustainable from unsustainable intensities. Above CP, W´ represents the finite amount of energy available. Both parameters describe the tolerance to exercise above CP but below pure sprints. The disadvantages of the traditional power-duration curve are that CP is not directly visible and W´ is even more difficult to determine as neither scale is expressed in work units.


This is where the work-power plot (Fig. 1) comes into play, showing the maximum amount of work that can be done at a given power minus the work done at CP. With a well-maintained power curve, a vertical line at CP and a horizontal line at W´ is expected. Therefore, both CP and W´ are clearly visable in one plot. In my example, the highest peak is at 500w, stemming from my 5min test from last week, which results in a 34kj W´ with an CP estimate of 391w. Also typical is the small decrease of work capacity above CP at higher power  outputs (more to the right) due to premature task failure before reaching VO2max at durations <2min.

For your own analysis you can use this expression in WKO (credits to William Renfroe):
@mmp:=meanmax(power),
@Pairs:=noinvalid((xx(@mmp),nozero((xx(@mmp)>=120)*(xx(@mmp)<=1200)*@mmp*xx(@mmp)))),
@CP:=slrm(@Pairs),
@W:=slrb(@Pairs),
noinvalid(nozero((@mmp,(@mmp<@CP+500 AND @mmp>@CP-50)*(@mmp-@CP)*xx(@mmp)/1000)"kJ"))

Then, put a vertical line at CP and a horizontal line at W´ and you are good to go ;)

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Anton Schiffer

Power testing part 3: 2min

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Lunch Ride

ROUVY - 60kg | VT1 test

Morning Ride

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Morning Ride

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