Floris wrote:
I've long thought about quitting my current training (1 day each of intervals, threshold, and long run, EZ the other days) and just run 10 miles a day (give or take a few miles), every single day. Alarm goes off, throw on my running clothes, and boom, out the door to run however I feel.
Why haven't I done this? I guess I'm too concerned I'll miss hitting system such as specific-endurance, speedwork, threshold. How the hell do you know if you're working these systems properly? If you're feeling like a racehorse one day, how do you determine if it's best to do a fartlek or an hour hard running? Questions, questions...
Do it already. It sounds like you're squeezing blood out of a turnip; you're doing the same routine every week and constantly struggling against diminishing returns.
It almost sounds like you've been brainwashed by one particular plan or coach. Keep reading and keep running. The more practiced and informed you become, the easier time you'll have making your own training decisions.
FYI, even a lot of the coaches who use the same jargon you're citing are advocates of periodization, which would involve focusing on each part for longer periods in order to maximize the benefit, rather than just throwing them all together every week and repeating it ad infinitum.