✅ Correct Explanation in Simple Terms
Here is the actual science simplified:
1. GH does two things:
Stimulates liver → systemic IGF-1 (blood)
Stimulates tissues → local IGF-1 (muscle, fat, organs)
2. Blood IGF-1 does not reflect local IGF-1
You can have:
High blood IGF-1 + low local response
Low blood IGF-1 + strong local effects
This explains why blood tests can look “bad” even if GH is active.
3. High GH doses give more effects even if blood IGF-1 stops rising
Because GH has direct, [tracking removed] effects.
4. Low IGF-1 blood results on GH do not mean the GH is inactive
Blood IGF-1 is influenced by:
Genetics
Liver sensitivity
Binding proteins (IGFBP-3, ALS)
Nutrition
Sleep
Stress
Time of blood draw
So two people taking identical legit GH can have very different IGF-1 numbers.
🎯 If you’re trying to assess GH activity for your customers
Tell them this:
The only reliable indicators GH is active are:
Increased water retention (especially hands)
Numbness or tingling (CTS symptoms)
Better sleep
Higher fasting glucose
Increased appetite after 1–2 weeks
Increased lipolysis (fat loss around waist)
Pumps in gym + vascularity changes
Blood glucose rises, insulin sensitivity drops
These effects happen even if IGF-1 test is flat.
Quoted ::
asiacally the systemic igf-1 level doenst tell you much. For anabolism the autocrine igf-1 is relevant. Thats why you have such huge difference in anabolic responses with similar igf-1 levels. Thats also the reason why even though systemic igf-1 didnt continue to increase in studys with more than 6IU rHGH bodybuilders report more anabolic effect with higher dosage.
In lower rHGH dosages systemic igf-1 has even a negative effect on autocrine igf-1 which seems to be overwritten at higher dosages and of course while rHGH increases systemic igf-1 which may surpress autocrine igf-1 it also increases autocrine igf-1 at the same time.