Golden Cheetah estimated FTP down

bflk
bflk Posts: 240
Been adding pm data to Golden Cheetah, 8 rides from 10th to 21st. On the 18th I did a long hill climb (Crow Rd outside Glasgow) and it kindly upped my ftp by 24W. :)

Today I did a gentler ride and it reduced it by 2W! :(

I checked the chart settings and it says last 2 months so its not a date range issue. I haven't changed any settings. What can cause it do to this?

The Trends section has masses of data history but can't see ftp there.

I've used GC for several years (sans pm) for both running and cycling and its always maintained the best figure to date (eg CV) so this is a new issue for me.

Comments

  • jgsi
    jgsi Posts: 5,062
    I think you are best posting on Google groups Golden Cheetah.
    At the moment my data for estimating w'bal is all skewed for the last few months and I cant make sense of what is wrong.
  • amaferanga
    amaferanga Posts: 6,789
    I haven't used GC for years, but if it still uses the Critical Power algorithm then 'FTP' can be adjusted down from doing power bests over shorter durations (~few minutes). If you don't think it's right just set it manually instead.
    More problems but still living....
  • bflk
    bflk Posts: 240
    I haven't done a proper FTP test myself yet so that is an option in due course I guess.
  • john1967
    john1967 Posts: 366
    bflk wrote:
    I haven't done a proper FTP test myself yet so that is an option in due course I guess.

    If your using a power meter then an FTP test should be your next ride.You cant realistically work out your training zones without doing one.
  • bflk
    bflk Posts: 240
    john1967 wrote:
    bflk wrote:
    I haven't done a proper FTP test myself yet so that is an option in due course I guess.

    If your using a power meter then an FTP test should be your next ride.You cant realistically work out your training zones without doing one.

    I set off on one on day 4 on the local flat TT course but bottled it partly as I have a minor groin niggle. I still rode it semi hard though so want to leave it a bit before I return.
  • john1967
    john1967 Posts: 366
    Good idea. No point in aggravating a minor injury.
  • john1967 wrote:
    bflk wrote:
    I haven't done a proper FTP test myself yet so that is an option in due course I guess.

    If your using a power meter then an FTP test should be your next ride.You cant realistically work out your training zones without doing one.
    There is more than one way to establish training levels and being precise with them isn't overly necessary. In any case, if you get them badly wrong you soon work out that training session are too easy or not achievable and adjust accordingly.
  • stueys
    stueys Posts: 1,332
    john1967 wrote:
    bflk wrote:
    I haven't done a proper FTP test myself yet so that is an option in due course I guess.

    If your using a power meter then an FTP test should be your next ride.You cant realistically work out your training zones without doing one.
    There is more than one way to establish training levels and being precise with them isn't overly necessary. In any case, if you get them badly wrong you soon work out that training session are too easy or not achievable and adjust accordingly.

    This. I’ve not tested for a fair while now, it isn’t really neccessy.
  • john1967
    john1967 Posts: 366
    Stueys wrote:
    john1967 wrote:
    bflk wrote:
    I haven't done a proper FTP test myself yet so that is an option in due course I guess.

    If your using a power meter then an FTP test should be your next ride.You cant realistically work out your training zones without doing one.
    There is more than one way to establish training levels and being precise with them isn't overly necessary. In any case, if you get them badly wrong you soon work out that training session are too easy or not achievable and adjust accordingly.

    This. I’ve not tested for a fair while now, it isn’t really neccessy.

    Of course its necessary .If you dont do an FTP test how can you know what your training zones are? Surely you cant be realistically happy with an FTP number that Golden Cheetah gives you? Is there any power based training regime that doesn't require an FTP test of some sort at regular intervals?
  • 1. Training levels are a convenience, not a necessity. They are arbitrary demarcations in any case. Training adaptations occur on a continuum with intensity.

    2. Training levels are useful for guiding training but they are also relatively broad (an in reality they overlap) such that precision isn't all that important, which is why e.g. training with nothing more than perception of effort can still be quite effective.

    3. While setting training levels relative to FTP is an entirely sensible thing to do (in particular for aerobic training), it is not the only means by which such training levels can be established. There are several methods. You might, for instance, simply base training on what you can actually do. Or use a Maximal Aerobic Power test, or various other options. e.g. with newer power duration models there are refinements to training levels based on specific individual characteristics. These can operate quite well without formal tests provided there is sufficient hard riding in the training mix.

    4. While testing to establish FTP is a good idea (and I've said so myself plenty of times), the point is that there are various means to make a decent estimate of FTP, and that if your only interest is in setting training levels then high precision is not all that important. Attaining precision with an FTP estimate has other values/uses.
  • bflk
    bflk Posts: 240
    I would say the Golden Cheetah data has pretty much converged on the right answer anyway. Since my initial post I've done an 18' then a 21' tough hill climb (Crow Road summit into a massive NE headwind) but I'm down to single digit W changes in FTP. I doubt I could match the latter climb power figures on the flat course so I'm pretty much done for now.