FTP dervied from shorter efforts

So I enjoyed some very nice breakthroughs lately (outdoor), the last one beiing achieved in a sub 1min climb (thats basically my speciality), which bumped up my FTP for 3% to a new all time high. However I’m struggeling with the harder HIIT on the Smarttrainer since. I’m using the Wattage from my PM on the Roadbike to control the smarttrainier as well. and calibrate the PM before every activity (indoor or outdoor). So could it be that XERT is actually overestimating my FTP based on those shorter efforts and I would need to correct it?

There are a couple of FAQs on this that you can refer to. If your PP and HIE are underestimated, shorter breakthrough efforts may end up overestimating TP. Sometimes however, the 3% differential may also be due to a power data error creeping into a shorter breakthrough effort. Errors in the data will have greater effect, the higher the power / shorter the effort.

Hi Armando, thanks for the reply. I actually read the FAQ about the underestimated HIE/PP. That might well be the case, as I did not do much serious sprinting outdoors this season yet and the actual PP might be higher than what I recorded. The Power Data creep would be a hardware issue though? Is there a way to differentiate that?

You can manually override the activity signature is likely your best bet.