sprinkfsu, the answer to your questions are dose and age dependant. some men over 40 can stay on 250mg test for the rest of their lives with no problems. if your talking like 750mg a week or more then its a matter of time, if your young then you risk completly shutting your natty test down for life by not cycling off. you can stay on as long as you like by switiching compounds but you will be making the sides worse on your body even with all of the precautions. most pro's have been on for 20 years and when they say they go off usually they are still using 250mg or 500mg test a week because their natty test levels are almost non existant. they call this idling. so you can stay on forever and run the health risks or cycle on/off and minimize the risk. it's your call, i have a friend who has been on for 5 years straight without a break and never once seen a doctor. he looks great but who knows what the damage is inside. this guy takes like 1g test, 600mg tren, 500mg deca a week, 150mg anadrol a day and 10ius GH. and this is not the highest he goes on dosages, actually this a low dose cycle for him right now. again though who knows what's goin on inside him