Just read “Fast Exercise” by the bloke that came up with the 5:2 diet. It’s all around HIT and is backed up with a reasonable amount of scientific study, much of it around cyclists.
HIT on a turbo 3 times a week suits me at this time of year as I can’t be bothered to do evening road rides when it’s cold. I’ll report back if it has detrimental effects on endurance if anyone is interested. I should mention I still do a long ride on a Sunday and HIT strength sessions on the two nights I don’t turbo.
I use a heart rate monitor for all training, otherwise how do you know how much effort you’re putting in? Recovery riding is important too, again using a HRM so you know you’re not working too hard.