if a 7mile is "sizable" ride to you then i would HIGHLY recommend against p90x/insanity type stuff (not that they're ineffective programs, qutie the opposite actually. but they're NOT for newbs and it pisses me off seeing them pushed like that. Going hard in HIIT style training is effective but it is difficult, and i don't just mean muscularly/mentally, but your joints and other stuff you may not be thinking of. You'd be capable of doing it, i imagine, but it won't be as effective or safe as other approaches if you're still very much a beginner)