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S-4 Questions:


OK, so this "SARM" and I don't want to go into the goofiness of that term, has piqued my interest.

Here's my basic understanding:

1 - Non steroidal molecule that stimulates androgen receptor
2 - non hpta suppressive
3 - not aromatizable or subject to 5ar

So, 2 questions:

1) could this compound be used to replace test in a stack w/tren, var, tbol, halo, etc., allowing a cycle with NO aromatizables ?

2)could you just stay on this stuff all the time? I guess the question is: would receptor downgrade be an issue?

Anyone with any PERSONAL experience with this compound would be GREATLY encouraged to respond here.


what exactly are you talking about?

and will it replace test, I would say the only thing to replace test in a non test based cycle like that is test.
I can not answer your other questions because I have no idea what a "sarm" is


Selective Androgen Receptor Modulator.

They are supposed to be the new wave of drugs that will allow any AAS taken alongside the SARM to ONLY activate the androgen receptors in muscles, thus removing the tendancy of AAS to cause prostate hypertrophy, enlarged pores, acne - all the androgenic sides that are unwanted - and possibly any other interaction of testosterone with enzymes like aromatase, 5-AR and SHBG.

They are new and not at this level of efficacy yet AFAIK, but it is theorized. I heard that there are a few supplement companies jumping on the hype bandwagon and selling BS supps that apparently allow your endogenous test to be better utilized. This is BS i am pretty confident however.

I have not heard of any drugs yet and have not looked into any - as Maddy asked, can we have links and some more information?

I dont think SARMS are supposed to replace testosterone, but work with it.. however i know nothing of this particular.... what? drug or supplement?

BTW - just because it has affinity for the AR, and is not suppressive does NOT mean it is an effective anabolic or PED... Take the AAS Mesterolone for example (Proviron).

Do you use AAS, or have you?

You DO know it is perfectly possible to have a totally 100% non-aromatisable cycle that wont give a drop in libido or require test dont you?
Just use Masteron or Proviron - both are non-aromatizing DHT based androgens that support libido and mood (as the DHT from Testosterone does).

I only mention it as you were looking into this 'product' to replace test to run such a cycle - but this is easily achieved with tried and tested AAS already.




This is not what they are intended to do, Brook. I know it seems like I've been pimping Bill Roberts lately, but he goes over them a little in this thread...


...and you can go here to read a little more about them (take it with a grain of salt).



From what i know, which isnt going to be a great deal as usual lol, The answer is no, a Sarm will not replace testosterone as part of a cycle.
The trials thus far for SARMS have all been at doses which have not invoked side effects, i.e attachment to the aromatose enzyme.

Using testosterone as your base at this point would be the wisest option until SARMS are proved either way to be effective for the same purpose.

IMO, the best thing that will come of Sarms is un-stigmatised prescription, As the makeup is not that of a steroid ring, it is in the eyes of the masses not a steroid, and for those who actually would benefit tremendously from an increased hormone profile - i.e the elderly, disabled, Sarms would be a massive breakthrough.


Thanks mate! :wink:


Don't want to cross any lines here, but supposedly a research chem company has included MK-2866/ostarine/S4 amongst its offerings... for rats, of course. I've yet to find it, though :frowning:


Testan: there will never be aromatase issues with this compound. It is essentially not a hormone, has no steroid ring structure, and is chemically incapable of being converted to estrogen, e2, or any other estrogenic compound.

Brook: Yes, I have used aas. Mostly short (4-6 week)cycles w/moderate dosages of test only (up to 500mg/w), though I've played with proviron within those cycles as well and not really seen a difference except in my pants (prov. make strong like bull!). In addition, I've always ran Swale's HCG protocol and done pretty non-aggressive SERM PCT and still recovered well. Never gained more than 15 lbs on a cycle, but I've never lost more than half of that post cycle, and I keep just about all of my strength gains, which is really my main concern. I seem to be estro sensitive (water and nips) even on a reasonable dose of AI (.5mg adex/day). So I've determined that I'm estro sensitive (or have a naturally high level of aromatase), but have a relatively resilient HPTA.

I would LOVE to run a non-aromatizable only cycle, but people seem to lose their doo doo if you mention running a cycle without test. I never FULLY understood why, as androgen receptors don't know what they're being activated by, and mast/prov would seem like it would make sense as well, and these compounds are theoretically less suppressive than test. However, these compounds have some drawbacks, in that they seem to have limited action inside of skeletal muscle, and they have all the normal androgen side effects. This is where the possible advantages of s-4 come in.

Theres SUPPOSED to be a reasonable amount of selectivity in S-4 (and I have access to real stuff, not the BS supplements), in that it binds to the AR in skeletal muscle as strongly as test, but in other tissues with 1/3 as much as test. COUPLED with the non-hpta suppressive nature of S4, one could create some pretty sick, minimally suppressive, non aromatizing stacks with other drugs out there (primo, var, halo, tbol, etc) that are also minimally suppressive. What would you end up with? A lean-gaining cycle, heavy on strength increase, with no ancillaries needed, and minimal pct, making recovery a BREEZE.

And if cows could fly, my oh my, but thats why I'm trying to get some ideas about this or at least stir the pot a little and see what ideas bubble up.

Alternatively: it could be das uber-bridge. A TRULY non-suppressive bridge. I wonder about AR downregulation though...

Oh yeah... its also perfectly legal to posess.

Longwinded, but this COULD be huge....


I ran it for 4 weeks at 75mgs a day,split into 3 sep doses with nothing else. It has a half life of about 4 hours in the body. Results were about the same as a light prop-dbol cycle. Great pumps,hardness,gained 5 lbs of lean muscle. I felt great throughout the cycle,not agressive like tren,but just alpha male. The general consensus is that there's no need to run it with test. I'm going to experiment with combining it with other compounds in the future,maybe EQ,or Tren. I think it will make a good bridge between Test cycles also. Def has some promise.


awesome! Thanks for the input!


Because estrogen is produced only from testosterone, androstenedione, or DHEA, the latter two not being very important, and if testosterone production is fully suppressed then estrogen production is insufficient.

Abnormally low estrogen is not a good thing.

That isn't to say that some modest non-aromatizable cycles cannot be okay, but the reason they are, when they are, is that they don't fully suppress testosterone production. However, they are also, for reason of this low dosing, also not very effective.

If you used enough of a "SARM" to achieve high activation of androgen receptors, then natural T production would be fully suppressed and estrogen would go too low.


So I am incorrect in thinking that S-4 is non-suppressive?

That would change things quite a bit.


According to the patent,dosages at or below 1mg/kg of bodtweight showed no suppression,with significant anabolic results. As Bill said,at higher doses you will prob be shut down. My research rat did very well with the prescribed dosages :slight_smile:


see... thats what I thought. And if the stuff is about 90% orally available, and about as anabolic as test, and one third as androgenic,
1mg/kg for a 100kg monkey would be equivalent to 630mg/week of test... nothing to shake a stick at, for a "bridge".

Now to solve the issue of AR downregulation....



Actually, AR downregulation may be more myth than fact. There are certainly diminishing returns in the presence of an AAS over time, but I suspect there are a number of other reasons for this.

From what I understand, the presence of androgens has been shown to significantly *increase the half life of AR receptors, which
is pretty much the opposite scenario from adrenergic receptors (ie. the clen situation). I'm basing this largely off of the monkey cell study of Kemppainen et al (full pdf downloadable at http://www.jbc.org/cgi/content/abstract/267/2/968.

There may well be current papers or theories that throw this info into doubt - so share 'em if you've got 'em.


Wow... this is turning out to be a great discussion. Exactly what I had hoped for! Keep 'em coming!

So IF what you're saying is correct, it WOULD be the perfect bridge, though I'm thinking maybe not a test replacer on cycle...

I'll have to take your word on the study, as that link didn't work.


Sorry about that. I noticed the paper wasn't coming up well so I had edited the post to point towards the abstract, but I guess that's still problematic.

www (dot) jbc (dot) org/cgi/reprint/267/2/968


OK, while I am a certified know-it-all, I'm no biochemist, so that pretty much went over my head... :frowning:

My understanding is that in the presence of androgens, androgen receptors stick around a little longer?


Exactly. It's definitely dry reading but you got the essence of it. As I wrote previously, this can be contrasted with the clen situation, where B2-adrenergic receptor half-life decreases in clen's presence.

Now there are obviously going to be differences between a cell line study and in vivo. Still, barring other experimental results, one has to consider other factors in explaining the homeostasis that we seem to eventually reach on cycle. A lot of it - though not all - may well be nothing more than our bodies needing time to get used to the changes that have taken place.

Alright, I'm starting to ramble...


Ramble away.

I guess the question is: will S-4 or any other SARM enable us to defeat that natural tendency to homeostasis?

What mechanisms could lead to that if, based on that study, AR downregulation would not seem like the likely culprit?