What is the reason low shbg needs ED injections?

[bixt]

Still don’t believe me? The best way to test this is to alter the constant in the above equation - alter the SHBG. Use Danazol or Stanazolol to drop the SHBG. And the function output (free test) will increase, by measurement or by formula. Then throw in some clomid, watch SHBG rise, along with a reduction in FT.

I just want to clarify that the above only applies when running the body in “manual mode” i.e. Exogenous test.

In a natural personal with a functional HPTA, if you try to fiddle with SHBG the body will compensate to keep FT at its set point.

 

[bixt]

In contrast, free testosterone is more akin to a flow rate, like the water entering the reservoir at one end

You have separated FT into two kinds. Input FT into the reservoir (I will assume from the source of the exogenous T), and output FT. And that they are equal. What goes in must come out.

How does the body control the FT entering the reservoir? Surely that is what would be determined by the pharmacodynamics of the ester and mode of administration etc?

On the other hand (in support of your hypothesis for “natural mode”), the body can control input FT through GNRH/LH.

But not for exogenous test.

 

[Cataceous]

Those discussions are your hypothesis yes, and I do believe the body will regulate to achieve a certain FT - but I’m adding the caveat that this is true only when natural with a functioning HPTA. Think of an aeroplane on autopilot.
...
You are in manual control of this aeroplane. The dosage injected is one input variable, the SHBG is a constant and the FT is the function output.
...

The same mechanisms are at work regardless of whether one is on or off TRT. On TRT I expect free testosterone to be proportional to the dose rate. My own measurements jibe with this. Please review this post. Unless you find problems with the basic assumptions you should reach the same conclusion. On TRT we do have "manual control"—and once you determine the proportionality you can predict and control your free testosterone with the dose rate, assuming steady state conditions. This is largely independent of SHBG levels.

...
Still don’t believe me? The best way to test this is to alter the constant in the above equation - alter the SHBG. Use Danazol or Stanazolol to drop the SHBG. And the function output (free test) will increase, by measurement or by formula. Then throw in some clomid, watch SHBG rise, along with a reduction in FT.

@readalot has performed this experiment—adding a steroid that reduced SHBG. Free testosterone did not change. Total testosterone went down.

Start from basic principles and see if you can find any justification for isolated changes in SHBG to affect free testosterone after a new steady state is reached.

 

[Gus80]

The same mechanisms are at work regardless of whether one is on or off TRT. On TRT I expect free testosterone to be proportional to the dose rate. My own measurements jibe with this. Please review this post. Unless you find problems with the basic assumptions you should reach the same conclusion. On TRT we do have "manual control"—and once you determine the proportionality you can predict and control your free testosterone with the dose rate, assuming steady state conditions. This is largely independent of SHBG levels.

@readalot has performed this experiment—adding a steroid that reduced SHBG. Free testosterone did not change. Total testosterone went down.

Start from basic principles and see if you can find any justification for isolated changes in SHBG to affect free testosterone after a new steady state is reached.

Interesting, based on your statements, I searched my exam sheet and what you said happened. I did tests on trt, 250mg of sustanon/week, right after I started a cycle with stanozolol for 3 months, maintaining the dose of sustanon and redid the tests. FT dropped from 39 to 29. Shbg from 18 to 3.8. E2 increased from 99 to 149 (unfortunately I don't have access to sensitive in Brazil). I had a lot of high e2 symptoms in that time, I gained a good amount of muscle mass, but I couldn't drop body fat, which was the goal. The curious thing is that among bodybuilders, dht derivatives are used to reduce e2, since many of them were developed for breast cancer in women, such as masteron.
Searching pubmed lately, I believe that there is an overestimation of the influence of testosterone on the reduction of shbg, and we forget about other factors since the articles show a strong correlation with fatty liver and insulin resistance. And in fact, before I developed hypogonadism, I discovered by chance that I had grade 1 steatosis.

Every study I've read to date claims that trt improves insulin sensitivity. But in practice we read hundreds of men who develop strong insulin resistance after trt. I'm one of them. If you have any scientific article on this, I appreciate it.
I only know Dr Paulo Muzy, a bodybuilder who claims that in patients with shbg <30 before the start of trt, there will be a great worsening in peripheral sensitivity to insulin.


This week I came across a site for a trt clinic that claims that their patients with low shbg actually respond very well to microdosing, resulting in increased shbg.

In the case of @Systemlord, apparently it had all the benefits of trt precisely when microdosed and especially after starting with Jatenzo, which has a very short duration, low dose and, from what I understand, reduces the chances of large fluctuations in free e2 and increase in insulin that cause low shbg.

Sex hormone binding globulin and insulin resistance - PubMed

Sex hormone binding globulin (SHBG) is a glycoprotein composed of two 373-amino-acid subunits. The SHBG gene and a promotor region have been identified. The SHBG receptor has yet to be cloned but is known to act through a G-protein-linked second-messenger system following plasma membrane...

pubmed.ncbi.nlm.nih.gov