Help with fitness signature. Realistic values for HIE?

I have always had trouble with the automatic signature xert gives me. Threshold seems way too high. I think I get a realistic MPA curve when I set HIE to around 56kJ and threshold at 320? But is it realistic to have such a high HIE? - Also I get confused with XEP, I thought this was something similar to NP. But why do I get lower values for XEP than for actual average Power sometimes, how is that possible?

It is my understanding the XEP issues I am mentioning result from the strange signature setting with such a high HIE.

Can you provide an example? Also, I would doubt that your HIE would be so high. Values above 40kj are very rare. If you look at your Power Curve (See Signature Calculator), your 1 and 2 minute power would be virtually impossible for you. You can attempt an all-out 1 minute effort to see where you can some close to. Recognize though that expressing your full potential at 1 minute is very difficult as much of it will depend on proper gearing throughout the entire effort.

My 1 min power is only around 800 I think. Maybe 900 with no power spikes over 1k, but its hard to test as you say. Maybe I don’t understand it. The thing is I can do 500w for at least 5:10 if I am fresh. this pic shows 490 for 6 Minutes, albeit up a gradient (I loose around 20w avg on the flats). 6 min allout

The thing is if I let xert fit a signature it claims approx a 400w threshold from that. But I cant hold 400 for even 20 min and during cp tests and races I struggle to hold 300w after just a few corners. This activity is a short race and during the second part this MPA curve resembles what I feel very accurately: Niere race I was completely spent during the part where the blue text is. I can only get a mpa curve like that with a low TP, because otherwise it will tell me I should be regenerating MPA

I am sorry to be taking up your time. I purchased a whole year of xert and I want to use it more, but I can’t make sense of these things. Maybe I did not understand some core stuff and you can point me in the right direction.

No worries Bjoern. What is most important for you is that the MPA data matches what you felt and what you are capable of. Have a look at this: If this matches you, then either just save it or, even better, go to an earlier activity and assign this to the its signature and save. I can now see how you HIE may be higher than most. I doubt it would go so far as being this however: