what test. enanthate? well, you can start 3 weeks after last shot if you want. BUT, at that point, test is almost completely gone from your system. What that means? no external test, no own test production = catabolic state. You lose muscle, you have high estrogen levels, in other words you are a girl. HCG should start the day of the last shot or maybe the week after the last shot; that way, once test clear your system, your nuts are already producing natty test; not fully recovered, but already in the process.