4-Androstenediol had become a popular pro-hormone to testosterone, before it was banned in early 2005. It was something that used to mix with many products because 20%-40% gets converted to testosterone. It was re-introduced by Patrick Arnold who claimed this new 4-Androstenediol showed that this new version had less chance of being converted to estrogen.
One needs to understand that 4-Androstenediol on its own was never a very potent pro-hormone, but it was effective when stacked together with other pro-hormones. It's called a "wet" hormone because it has the ability to convert into estrogen and not testosterone.
Before 4-Androstenediol was banned, athletes taking 250mg doses showed that it lowered blood pressure but also had a bit of water retention, bloating. In the days before sports science fully understood anything about pro-hormone conversion, 4-Androstenediol had been used to enhance delivery systems, improving its bioavailability.
Before 4-Androstenediol was officially banned in 2005 athletes would take it sublingual because this would help to by-pass the intestinal tract, which provided better conversion into testosterone. 4-Androstenediol esters were also popular, giving this hormone an ability to get picked up by lymph fluid delivering a much more efficient way of getting standard 4-Androstenediol absorbed orally.
The side effects of bloating and hair-loss were very common, also many athletes showing more aggression together with gynocomastia. These common side effects when taking 4-Androstenediol were due to a lack of understanding on pro-hormone conversion.
Now banned is USA, 4-Androstenediol is still available legally in a few countries but this pro-hormone was never an athlete's best choice for a pro-hormone. It was an effective advancement on standard 4-Androstenediol preparations. Androstenediols are steroids, which directly affect estrogen and testosterone levels, just like all other steroids.
Since the new Anabolic Steroid Control Act of 2004, all Androstenediol preparations have been reclassified to a schedule III controlled substance. Meaning androstenediol is now only available on prescription from physicians that have very strict rules to follow when prescribing it.
For example, a physician may prescribe 4-Androstenediol for someone with a low daily T production. This schedule III medication will increase production of testosterone; enhance recovery from any exercise, increase energy; enhance recovery and growth from exercise and heighten sexual arousal, promoting a much greater sense of "well-being".
In conclusion, although the NCAA (National Collegiate Athletic Association (NCAA) has officially banned Androstenediol, studies show that it does not help to increase strength and muscle size when taken orally for 12 weeks and doing resistance training. Despite what is written above, Androstenediol studies do not show that it will increase energy, improve recovery from exercise, heighten sexual arousal etc.
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