How do I set W Prime in Power Options?

[Steve Tucker]

Or not so much how, as where do I get the correct number to place in the Athlete Power Options? Currently it defaults to 20000

[Christopher Battles]

Hey Steve,

We're on the same wavelength today; the link below gets close to answering our question. I think user Hamish is saying that the W' on your CP curve is the number you plug in (of course multiplied by 1000 -- i.e. 14.6 kJ = 14,600 J). However, that's my interpretation... 

"Look on the CP chart and in the box it will tell you W'. Then just enter it in the preferences..."

https://groups.google.com/forum/#!searchin/golden-cheetah-users/w$27$2020000/golden-cheetah-users/iIZV2ZwzHRs/vn0NH2NSwaYJ


p.s. Just got into GC and power meters in the last three months. What a fantastic job Mark and the others have done.

Chris

[Steve Tucker]

Hi Chris and thanks for the reply.

I'm new to power too. Agreed about the great work of Mark et al. Fantastic!

I followed the thread and input the number from the W value on the CP Model.

I added new CP numbers from my first ftp test yesterday.

The issue now is I am struggling to get the W expended % below 100%. If I put the number from the CP model in W it still stays red, if I up my CP by 10 which is correct it drops down to 89% for that ride

but if I up my CP by even more it goes back into the red.

Wish I understood W Prime a bit more, though I have watched the video.

[Christopher Battles]

It seems like we're jumping in at the right time; a lot of new publications out there and a few tutorials... trouble is translating a new thing, let alone one this complex, is difficult! Let's see if we can do it.

 

I think I'm reading from you is:

- You did a CP test (way to go, that hurts! congrats)

- In athlete>power>critical power area in Preferences: you entered your W' value from the CP Model and things just don't line up

- You're looking to get the "W expanded(%):" in the ride Summary tab at or close to 100%

In my amateur but curious mind:

1) When entering the numbers into the athlete profile: 

√ Make sure the W' value is transferred right 

√ Enter the CP value you have, not the one in the CP model box.

2) Backdate the test to the appropriate (or preceding) date.

3) CP test data must be only of the test duration..stochastic outliers and fluctuations can bump the W expended % up a few points, even on a low intensity ride.

4) 89% is a pretty good approximation for the first time doing a test... I don't know your background or level, don't want to insult your knowledge or riding level. In what I've read and experienced (having done four now) is that I'm still building the fitness, focus, and feel to even do a CP 30 test reliably. 

[Steve Tucker]

Cheers Chris

I eventually settled on the number from the box in the CP model. No idea how good a measure that is but it will have to do for now. Need to find some more material to read up on the subject though.

Kind regards

Steve

On Saturday, 21 February 2015 18:11:51 UTC, Steve Tucker wrote: