Silly question perhaps, but how does it set you back? It doesn't make sense to me (I'm a slow learner, lots of things don't make sense) Please correct my thinking!
I keep thinking that while your in base, working aerobically, your building your new capillaries, teaching your body to burn fat for its energy... But, when you stop working aerobically, as soon as your heart rate reaches its resting rate, you make no gains until you start working aerobically again. All of your gains come from when your working, not from resting (unlike weight training).
And if thats the way it works, then I would think that you could spend 3 hours spinning pedals... working in base, and then for the last hour, kick it up to a high anaerobic level for the last hour and get the best of both worlds. If your base gains come from doing the work, while the works is being done, how can working anaerobically directly after reverse those gains? If it was possible to reverse them, you would reverse them even after you spent your 8 weeks in base, and started working anaerobically after that!
I know I'm wrong... But I'd like to know why... where... and how...
(now I'll resume my position at my desk, in the front row, staring at the chalk board)
(might even sit on my hands, so the ruler can't find my knuckles)