Are you estimating 20 HIE based on this bell curve chart?
Are there errors in my Fitness Signature? – Xert
You can manually edit a signature to establish a starting reference point to train with by entering values on your last activity chart then Save (lock).
E.g. lower TP to 290 and raise HIE to 20 then validate by performing a fitness test.
Indoors a fitness test should be ridden entirely in Slope mode especially when establishing a signature –
Related topic – Initial Setup Issues - TP seems way off - Support - Xert Community Forum
Reference – Breaking Through the Xert Way! – Xert