Continuing on the "do what works for you" long would you continue with a particular routine/regime to see if it "works" for you? 5 days? 4 weeks? 10 weeks?

I am not gonna use the right terminology here - but to what point does "if it ain't broke - don't fix it" hold true versus you have to shake it up ... foods eaten, exercises and motions performed, etc.? I try to change up my food pattern and exercise routines ever 4-6 weeks just so I don't get bored.

I would think that too short a time frame and the effect would be like shocking your system ... it may work for a quick spurt but not be a good routine to follow long term.