Originally Posted by
PeteHski
Good question. Over the last month I’ve averaged about 40 mins per week in Z5. As a percentage of my total monthly time Z5 was just over 13%. Looking back to last year it was typically under 5%. So quite a lot more focus on Z5 now.
Both my FTP and VO2 power metrics are trending significantly upward after sitting on a plateau for about 18 months. It’s too early to say what effect this will have on my endurance as I’m not doing any really long, hard rides yet. But I’m certainly at the top of my game on sub-2 hour rides.
OMG. IME it won't hurt your endurance, but it sure can bite hard if you go over. Though if you keep this up, it will cut into it. I see why you do so well on so few hours. I only do that sort of thing to peak before a taper but I'm more delicate.