IGF-1: By Anthony Roberts

Insulin-Like Growth Factor 1 (IGF-1)

by Anthony Roberts

Insulin-like growth factor 1 is a growth factor which is very closely related to insulin. It carries the same amount of amino acids as insulin and responsible for the anabolic reactions to GH. IGF-1 is an important factor in childhood growth and is highly anabolic in adults.

Background

In the 1970's, IGF-1 was known as as "Sulfation Factor" and "Nonsuppressible Insulin-like Activity" (NSILA). In the 1980's, it was known as "Somatomedin C." The most popular type of IGF-1 available on the Black Market is a longer lasting version (more amino acids in length) known as Long R3 Insulin-like Growth Factor-I or Long R3IGF-I. Lr3igf-1 is more potent than the lesser versions which are no longer available on the black market. Of that type of IGF, there are two types commonly available (Media and Receptor grades, respectively). These last two types of IGF mostly just refer to the purity of what is actually in the bottle.

Action

IGF-1 is released in the liver and binds to the IGF receptors within the cells, which ultimately causes a stimulation of cell growth (both causing new tissue formation and existing tissue growth) and an inhibition of cell death. It is a highly anabolic and anti-catabolic compound. For the athlete or bodybuilder, this had many positive effects: increased nitrogen retention and protein synthesis because it is highly anabolic. IGF-1 (in the presence of sufficient protein) actually promotes growth of new muscle cells, which increases the overall number of cells in the muscle.

IGF protects the neurons of the brain as well as promotes growth of new motor neurons, making it more possible to rapidly learn new skills during its use. IGF-1 is also responsible in connective tissue production, improves collagen formation and aids in cartilage repair. Similarly, it affects the bones by aiding in bone production and repair.

Technical Data

In a study done on young adult mice, a compound responsible for increased secretion of IGF-1 in muscle fibers was administered. There was an average increase of 15% in muscle mass and a 14% increase in strength. When the study was then conducted on adult mice, there was a 27% increase in strength in the injected muscles as compared with non-injected muscles. It was also found to prevent aging of the muscles. Muscle mass and muscle fiber growth were similar to the levels found in young adults. These effects are most likely due to the ability of IGF-1 to activate satellite cells, therefore stimulating muscle rejuvenation (1).

In studies conducted where GH and IGF1 were used together, a greater increase of Lean Body Mass and fat reduction was found than by use with each compound alone (2). Researches also believe that use of testosterone would also increase IGF levels in muscle (3). In a 12 week study on subjects using IGF-1, IGF-1+GH, or GH alone subjects in this study, gained around 3kgs of lean mass, and lost around 2kgs of fat(4) .

The complete human IGF-1 Long R3 IGF-1 is 2-3 times more potent than IGF-1 due to less ability to be made inactive by IGF binding proteins (5) (6).

User Notes

I’m actually a very big fan of Lr3 IGF-1. For me, I’ve found that it’s had beneficial effects on helping me recover from training injuries and has shown to be very helpful in improving my strength, speed, and performance. I also noted some pretty enhanced muscle building effects and very enhanced fat burning when I’ve been on IGF…nothing on the level of Anabolic Steroids, but still, the effect was very pronounced.

Most users opt for a dose of about 100mcg/day injected bilaterally in the muscle group just trained, immediately post workout.

I suspect that in the coming years, more and more professional athletes will be using IGF, as it is very difficult to test for, and many have switched over from GH to this compound already.

Anecdotally, IGF seems to stack best with Trenbolone and Testosterone, and there’s certainly some synergy between these compounds. Lately, MGF is being added to most IGF protocols. For a fuller discussion of how has been done, check out my article “Peptides: The Next Frontier in Hypertrophy."

Trivial Name
Insulin Like Growth Factor 1 (IGF-1)

Systematic Name
Somatomedin C

CAS Number
7733-29-1

ATC Code
H01CB02

Merck Index Number
N/A

Molecular Weight
7649 daltons

Bioavailability
99%

Metabolism
Almost all tissues

Elimination Half Life
Variable

Excretion
N/A

Legal Status
Varies
Route of Administration
Subcutaneous injection, Intramuscular Injection


References

Viral mediated expression of insulin-like growth factor I blocks the aging-related loss of skeletal muscle function.Proc Natl Acad Sci U S A. 1998 Dec 22;95(26):15603-7.
Recombinant human growth hormone, insulin-like growth factor 1, and combination therapy in AIDS-associated wasting. A randomized, double-blind, placebo-controlled trial. Ann Intern Med. 1996 Dec 1;125(11):865-72.
Am J Physiol Endocrinol Metab. 2002 Mar;282(3):E601
Am J Physiol Endocrinol Metab. 2002 Mar;282(3):E601-
IGF-I variants which bind poorly to IGF-binding proteins show more potent and prolonged hypoglycaemic action than native IGF-I in pigs and marmoset monkeys.J Endocrinol. 1997 Nov;155(2):377-86.
In vivo actions of IGF analogues with poor affinities for IGFBPs: metabolic and growth effects in pigs of different ages and GH responsiveness. Prog Growth Factor Res. 1995;6(2-4):385-95. Review.

good post action, although 100mcg is a large dose and will have alot of 'spill over' into systematic use......therefore causing perma-bloat-ronnie coleman-gut!

from what ive read 40mcg is best 50mcg if quads for local growth for anyone thinking of using.........anymore is too much and you'll end up growing new intestines in a few months!!!

Originally Posted by tom123

.anymore is too much and you'll end up growing new intestines in a few months!!!

Sweet, so your saying I can eat more food then LOL

I am liking the fact that this article claims test and tren are perfect for use with IGF, and I am using both ( along with GH)

I am rather curious as to how he came to the conclusion they are sinergisitc?

Good point...If it's Anthony Roberts though, you can bet your ass that it's the truth...He knows his shit and backs it up with references and studies...

Originally Posted by Action

Good point...If it's Anthony Roberts though, you can bet your ass that it's the truth...He knows his shit and backs it up with references and studies...

I agree wholeheartedly

He is one of the few who seems to wade through the bullshit and also back it up with theory. Something many of the zine/website owners rarely ever do.

Its funny, this combo made me gain weight very very quickly, its already tapering off, but I am guessing that the amount of fat I am currently loosing makes the difference. My abs are getting pretty solid and my overall appearence is getting more toned then it used to be. And this is all while I am munching back 5000 calories min a day.

That and the fact I am only at week 4 of a 3 month cycle

Ya...You gotta love the combo of GH and IGF...Now, add some PGCL to that combo and watch the fun!

I can't wait...