My query is more a holistic one around the algorithm for FTPs and breakthoughs. In the last 2 weeks I have recorded best ever powers for both 20 minutes and at the other end of the scale, 30 seconds. Neither of these were breakthroughs. I’ve read the info re FTPs and variation et al. So it seems the Xert algorithm is more heavily weighted toward efforts in the 3-8 minute region, because of the cumulative effect of hits on the MPA. And for the 20 minute power, is it just that it does not dip into these reserves at all? TIA
Hi Deborah,
The algorithm looks at the data as a whole, finds the point of an activity that results in the largest change to your fitness signature parameters, and assigns that as the breakthrough effort. It could be that you tend to see more breakthroughs in the 3-8 min region because you have been training your HIE, which is a larger contributor to those types of efforts. Also, remember that Xert’s power duration curve is not a MMP of your best-ever efforts, but is meant to show the maximal effort that you could put out based on your existing data. How close was your 20 min effort to a breakthrough?
Hi Scott, thanks for the response. It’s more an observation from me of the difference in the algorithms. Xert currently pegs my FTP at 240 and for the 8 minutes 5.4 w/kg. As you know, most other reference is to FTP calculated from 20 minute power and multiplied by 0.95 to convert to the hour. Currently mine is 201. So very different. Interestingly, the 8 minute calculated this way is closer at 5.2. The 20 minute power best was flagged as a best ever FTP on every metric I currently look at, except Xert. It was not even close to a breakthrough on Xert. As a scientist I understand to compare within algorithms, but I am interested to know if any other Xert users have experienced similar results to this.
Hi Deborah. I reviewed your profile and I see that your HIE is quite low. HIE low / TP high errors can manifest sometimes when performing workouts, unwittingly. They can also occur when PP hasn’t been properly established. Send a note into support@xertonline.com and someone can help you identify the cause. Xert should always be precisely identifying a realistic, achievable power curve ride by ride. If you wish to troubleshoot this yourself, you may want to do a progression recalculation using a good starting signature and look for rides where your signature may be misrepresented then flag them.