I wouldn't consider tabata to be "shorter" per se -- at least not clearly. There is no full recovery between them, so your average power will still end up in the same range. It's just a less steady effort.
I think there is some value in doing both types since the irregularity of Tabata can simulate race conditions a bit. 5x5m seems more efficient to me, but I think your mood and motivation would have more to do with actual results than which of these you choose.
You need to work on your mindset. I would do 5m intervals every day if it wasn't counterproductive. My kind of suffering -- even though I'm stronger with shorter efforts -- I just enjoy these.
Originally Posted by
NomadVW
I'm hoping to start next week at 400-410.
Rockin! My 6x4m workouts are averaging 390W right now. 365W for 5x5m. I got you by more than a few lbs though!