TL;DR tempo HR in 8x4 sessions, huh??
I’ve been doing sets of 4x8min at 103-105%FTP and 30/15s at 120-130%FTP. These have been done on both the road and trainer, but my HR as a percentage of both max and FTP is low.
Although it’s been a few years since I’ve trained seriously this years numbers are consistent with what I’ve seen before a max HR of 201 and threshold of 181 with a resting of ~50. These numbers were taken from test on the trainer this year - but I see similar during races and during outdoor tests in the past.
VO2 zone is either 190+ with the 7 level model, or 177+ for the 3 level model from Seiler. During a recent set of 4x8 (outside) HR average for all for intervals was 162-169bpm maxing out at 177 during the last minute of the last interval. This seems inconsistent with the proscribed HR guidelines for the session, and that I’m on my knees for the final minute. Though 30/15s I feel that 130% FTP is within my capabilities. Doing these on the trainer - I do have a higher HR, but not massively so - I’ve put this down to cooling and other issues with riding indoors.
So - carry on with intervals as they are? Or use hard starts to get the HR up during the 8 minute intervals, if so how hard for how long?