After warming up for a bit, I did 1:2:5:2:1 intervals. My recovery time between each was enormous - I waited until it got down to ~60-65% of max, but the darn HR just didn't want to go down quickly.
On the first interval, I hit a new HR high; not sure what it was - just had the screen showing %HR, and once I went over 100% (of manually entered max HR), it just showed "HI". Nice.
But on the subsequent intervals, I couldn't get over 98%, and on the last one, only got to 96%. Does that mean my muscular endurance and strength aren't high enough to really push my HR repeatedly? I guess it could be a mindset issue, but I really was trying to get to 100% of max HR, despite my legs' protest. How critical is it that HR reaches max HR by the end of the interval?