Comparing 2 extreme examples:
Version 1 - 1x50 minutes @ 90% + 20 minutes in Z1
Version 2 - 5x10 minutes @ 90% with 5 minute rests between each Z1
Comparing the 2 versions, it’s the same time in SS and Z1 zones. Same TSS.
Version 1 is obviously mentally and physically harder, but should be very doable at 90% of threshold.
I feel like version 1 would certainly help train the mental fortitude needed for these kind of intervals, but I was curious what the physical adaptation benefits are. I’m also curious how much additional stress this may cause and whether it’s a good tradeoff (same TSS, but seems like it would create more stress).