If LH and FSH levels are low, same is diagnosis for secondary (hypogonadotrophic) hypogonadism. A problem here is that LH has a very short half-life, and its production is quite pulsatile, so serial draws must be done in order to develop a picture we can rely upon.
Gonadotrophins will be elevated in primary hypogonadism. There is also a "mixed' variety where both ends of the axis are deficient.
We should distinguish betwen acquired secondary hypogonadism (for instance secondary to
AAS use) and the general decline in testosterone production brought on by age ("andropause"). In the second case, the problem is one of testicular failure, so no amount of "jump-starting" is going to result in any stiffness in the mornng other than the back.
I have had success restarting the HPTA in former steroid athletes, even long-term after cessation of anabolics. It's always worth a try, IF the patient wants to. Most simply prefer going straight to the Upjohn
test cyp injections, though.
Distinguishing between primary and secondary testicular failure 
Linear Mode
