Most of us know by now how esters work and their importance in our cycles. I would like to share my opinion on how different esters work with each other to coalesce into a single stream. Different esters release free testosterone at different rates. This is common knowledge; the question is what happens to that testosterone once released from the ester? It is my intention to illustrate this question in the simplest and most straightforward way possible.

Disclaimer:
I am in no way a medical professional, PhD or pharmaceutical representative. I am an engineer and math is second nature. That being said the following post is my opinion based off of pharmacokinetic equations and theories. I have charted any and all graphs, illustrations and tables using Excel.

Abstract:
This paper is about how different esters combine to create a homogenous stream of testosterone primarily using Sustanon 250 as a basis. I will first illustrate how a basic Testosterone enanthate ester releases a daily amount of free testosterone into the bloodstream. I will then illustrate how this affects our plasma levels and leads into a taper. This will demonstrate how different esters can affect our PCT and the importance of timing to maintain and or keep our gains. Finally I hope to generate questions that will lead to more in-depth considerations on the subject.

How esters work
By now I think most of us understand how esters work. Each ester has a specific half-life that cleaves off testosterone into the bloodstream, acetate and propionate being amongst the shortest of the esters. Consequently decanoate, undecanoate and cypionate being the longer esters take more time to release free test into the bloodstream. Starting off with testosterone enanthate we know that the half-life is 8 to 10 days. This means that approximately every 8 to 10 days the original dosage is cut in half (Half Life Math). Now testosterone enanthate has a test base of 70%. This means that for every 100 milligrams of testosterone enanthate there is approximately 70 mg of testosterone. It is therefore surmised that every day 70% of the daily dosage released is freed to attach to receptors. So imagine if you will a large stream flowing through a ravine. Now imagine a tributary connecting to that stream that flows into a larger body of water. The mainstream in this case is the testosterone flowing to the receptors in our bodies and the tributary is the ester releasing free testosterone to flow into the mainstream. See illustration 1.

So for illustrative purposes let’s take a single shot of 100 mg of testosterone enanthate. Knowing what we know about the half-life of this ester at day two we would have 91.7 mg in our body. Now the difference between the 100 mg and 91.7 mg would be 8.3 mg. 70% of that 8.3 mg would be 5.81 mg of free testosterone. (At this point I would like to make it clear that we are dealing with just milligrams for the entire body, the actual plasma level is represented using the nomenclature nanograms per deca-leader or ng/dl). At day three we would have 84.09 mg of enanthate in our system cleaving off the difference between 91.7 and 84.09 multiplied by 70% equaling 5.33 mg of free testosterone and so on and so forth. So you can see that the free testosterone is 70% of the difference between day one, day two, day three and so on. See table 1.

Table 1

If we were to use the table above as an example starting with a 100 mg shot then we would see that over the course of 71 days it would release small amounts of testosterone into the mainstream daily until it reached zero. Graphically it would look like illustration 2.

Illustration 2

It is easy to see at this point how the last injection or known amount of testosterone tapers off naturally. This is sort of analogous to a steep cliff wherein one could easily fall down and crash. This is what is meant by a post cycle crash. It is the point where natural production of testosterone cannot ramp up to the previous levels introduced through extraneous injections. This leads into a proper taper at the end of the cycle mitigating the painful loss of gains due to post cycle crashes. This is relevant to our PCT regiments in that if one could calculate the amount of short ester testosterone necessary to gradually reduce or lessen the slope of the curve, we could give our bodies more time to rebound back into a homeostatic state. I will address this point shortly.

Test is test
The heading says it all. Using the theory of a homogeneous stream of testosterone we can expound on the principle that esters work individually to contribute to that very stream. What I’m saying here is that it doesn’t matter what testosterone blend or ester we use, each blend or ester releases testosterone daily or hourly even at its own rate, but it all goes to the same stream. We will use the classic Sustanon 250 as an example. Starting with Testosterone Propionate at 83% with the half-life of two days all the way to Testosterone Decoanate at 63% with a half-life of 15 days, we will see how each ester individually contributes to the mainstream. See table 2.

Using the table above and the previous analogy of a large stream running through a ravine with several different tributaries connecting to it we would get a graphical representation like illustration 3.

Illustration 3

The mainstream of test is now free to bind to other receptors. What’s important to note here is that each ester releases its own specific amount on an hourly basis until it has diminished itself to zero. So starting with Testosterone Propionate at 30 mg would take approximately 24 days to reach zero and Testosterone Phenylpropionate at 60 mg would take 44 days to reach zero followed by Testosterone Isocaproate at 60 mg would take 87 days to reach zero and finally Testosterone Decanoate at 100 mg would take a whopping 140 days to reach zero. See illustration 4.

Illustration 4 (In this graph at 90 days the amount is actually .05 mg of test, it actually takes 140 days to reach zero)

Notice how steep the slope is with only one shot this explains why intervals are spaced so closely together when running a Sustanon cycle. However, this begs the question; how much test needs to be in our system to shut down natural production? This would be a huge factor in when we start PCT.

Putting it all together
So knowing that esters release testosterone at an individual rate let’s see what a simple Testosterone enanthate cycle would look like at roughly 1000 a week for 10 weeks with a two-week Propionate taper. See illustration 5

Illustration 5

Keep in mind these graphs represent the actual testosterone in the blood and not the ester. I make this point so as not to get confused with my previous graphs on other papers.

In this illustration I’m showing a Test E cycle of 12 weeks. However, I have stopped the enanthate ester at 10 weeks. This is where it gets interesting if I were to immediately on the last day of the 10th week inject propionate to start my taper, I would see a noticeable spike above the 150 range. This is not really beneficial to us and in fact is extra shots and money. It is better in this case to start the propionate taper five days after the last enanthate shot. By using the propionate to taper we can see how much we can lessen the slope after cessation of a simple cycle which gives our bodies ample time for PCT to kick in.

I know this is way more in depth then most people on here want to get and you do not need to be able to do the math to understand these simple principles, however, by understanding how esters work together you may be able to build smarter and more efficient cycles and that's what it's all about. Right? Thank you for reading.

Other posts I have written that may help you understand the science behind this paper:
Half Life Math
Maximizing Cycles

C.H.