My regular routine would be seven weeks of any particular program, normally this would be with an emphasis on a specifcally lagging muscle group. I would measure and guage success at the end of the seven weeks, take an entire week without doing any exercising what-so-ever and not sticking with any diet plan either(not pigging out, but not counting cals either) Then redesign my workout and dial my diet in for the next seven weeks. This seems to prevent my body from figuring out my routine. My workouts could change dramatically or simply shift the focus to a different bodypart by keeping the workouts the same just changing the rep range for a few muscle groups. It also allows my body to totally and completely recover from the intense abuse of hardcore lifting for the seven week program.