Originally Posted by rsbob

This is something I have been wondering about since the beginning of this thread. Doubt any research exists at this time that discusses majority low effort punctuated by a few intense one. Do the higher level efforts negate, compliment, or increase the benefits?
Where I live, it’s impossible to sustain Z2 for hours on end without having climbs of 10-15% without constant doubling back. I too like breaking up effort levels just to defeat the boredom aspect.

In the same way, there are days when I just go out and stay in Z4-5 with occasional forays into anaerobic just because I like working hard, but then I am trashed the next day. I really dislike doing intervals, which probably means I will not be improving but at least I won’t be hating working out.