I can tell you that myself, after huge doses of every roid under the sun, no gh or slin anything like that, after about 4 years of huge abuse doses, my levels were at about 200 ngl, which is almost the lowest it could be, so add about 10 years to that of a pro bber, and basically when the person gets off juice and drugs their hormone system is totally destroyed, actually I was able to revive my testosterone through rest and good old time, it took me about a year and 2 months to feel normal, actually my test level came back stronger, I was actually lucky to have the access to extreme labs supplements which actually a few of their products like natural test depot and woody allowed my natural level to spike up high............my advice to guys who want to juice is to take doses for about a month at a time, that way your system doesnt become totally dependent, and keep the dosage low, a person can actually take 250 mg of sostenon twice a month and keep the natural test production there. My theory is on the month use, your body is just acclimating to the sythesized test, if you actually use low doses and supplements to keep the leutinizing hormone working you can actually do your body good. However the huge doses for months at a time can destroy your system. Actually 10 mg of anavar a day is enough to totally shut down your natural test, take care guys.