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strong man military pressEstra-4,9 is known as dienedione and may be listed under the nomenclature 4,9-estradiene-3,17-dione. It is similar in structure to trenbolone and shares some of its characteristics but it actually converts to dienolone. The conversion rate of estra-4,9 to dienolone is unknown. Conversion of estra-4,9 to dienolone is probably accomplished through the action of the enzyme 17b-HSD. This is usually not an efficient method, typically yielding about 10% fully active steroid. We can assume that the conversion rate to dienolone is low, which is demonstrated by the high doses needed to see results. Estra-4,9 does not have much androgen receptor binding affinity on its own, so most of the effects seen with this compound are a result of conversion to dienolone.

Estra-4,9 is typically used for cutting cycles

It can produce quick gains in strength and gains in size over time with minimal bloating. It probably does not convert to estrogen so the small amount bloat that may be experienced with estra-4,9 should be a result of its progestational effects. Estra-4,9 also seems to have some type of thermogenic effect, increasing the metabolic rate and aiding in fat burning.

Not very androgenic and cannot convert to DHT

Estra-4,9 is not very androgenic and cannot convert to DHT, but it may be converted to other 5-alpha reduced metabolites. The anabolic to androgenic ratio of dienolone has been said to be about 100/10. Androgenic side effects should not be too bad with this compound but as with any steroid or prohormone they are still a possibility. Estra-4,9 may not convert to estrogen, but gyno is still a possibility, This may be due to the fact that it is fairly suppressive to natural testosterone production while not having much for androgenic effects, which causes a disruption of the estrogenic/androgenic ratio when estra-4,9 is used alone. This disruption may also cause a decrease in libido. Estra-4,9 is not methylated to increase absorption so liver stress should not be an issue.

Short half life, low bioavailability, low conversion rate to dienolone

Estra-4,9 has a very short half life, low bioavailability, and likely a low conversion rate to dienolone. This necessitates large, frequent doses. Taking estra-4,9 with a fat containing meal is a good idea as it may improve the absorption of this non-methylated compound.At this point Estra-4,9 has been banned but oddly dienolone, the active version of this prohormone, is still available and not listed as a controlled substance. Dienolone is a gray area over the counter steroid, and may not be be available for much longer as it does not meet the requirements for what can be considered a dietary supplement.

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Roberts, S (2009). Anabolic Pharmacology.

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