Review of Sports Pharmacology by Yuri Bombela

16/06/2026

It is well known that synthetic testosterone is used as a contraceptive for men – excessively high levels of this hormone suppress fertility. However, equally, too low a level of testosterone can also lead to an inability to father children. I will now explain why this happens and what the implications are.
What do we mean by male fertility?
It’s quite simple: male fertility is the ability to produce s***m, the male reproductive cells. And in truly vast quantities: to maximise the chances of conception, a single millilitre of ej*****te must contain at least 20 million s***m, and the total volume of ej*****te must be at least two millilitres.
But even these are not the only required conditions: s***m motility is also important (at least a quarter of the total count must be motile), as is their correct shape (at least 14% of s***m must be free of defects). S***m motility, count and shape can be assessed through a test known as a semen analysis.
There are two further facts that are important to us. Firstly, s***m are produced in the testicles — or, more precisely, in the seminiferous tubules — and the Sertoli cells found there play a vital role: they nourish the s***m and enable them to mature properly.
And secondly: the full cycle of s***matogenesis lasts 73-75 days (according to some sources, even up to 90 days). So if you’re experiencing fertility issues, I’d advise you to be patient — it will take a long time to recover.
S***matogenesis begins in adolescence and, in theory, can continue into old age. In practice, however, s***m motility begins to decline once a man reaches the age of 40-50, and one of the reasons for this is a change in hormone levels — primarily testosterone. Although it is not only testosterone, but also follicle-stimulating hormone (FSH).
On the role of testosterone
Yes, FSH and testosterone have a major influence on s***matogenesis. The former initiates the process of s***m production; without FSH, nothing will happen. However, simply initiating the process is not enough: as you know, there needs to be a large number of s***m, and they must also be healthy and motile. And that’s where testosterone comes in.
This is because it is testosterone that acts on the Sertoli cells, causing them to release the nutrients needed for the development of s*x cells. If testosterone levels are too low, there will either be an insufficient number of s***m, very few healthy ones, or their motility will be poor. Most likely, it will be a combination of all three.
You’ve probably noticed that I haven’t specified which type of testosterone I’m referring to. Generally, total testosterone levels are taken into account: it is believed that if these fall below nine or ten nanomoles per litre, problems with conception may arise.
However, recent research suggests that the s***m count and motility in men with total testosterone levels of around 8.64 nmol/l (to remind you, this is the lower limit of the normal range) are virtually indistinguishable from those in men with much higher total testosterone levels.
However, the picture changes dramatically if we consider not total testosterone levels, but free testosterone levels. And not just that, but also dihydrotestosterone levels, which also play an active role in the process of s***matogenesis. Too low levels of these hormones will almost certainly lead to problems with conception.
Let me emphasise: these are merely issues. Neither a follicle-stimulating hormone level that has fallen below the lower limit of the normal range, nor a free testosterone level hovering around zero, means that conception is impossible. It’s just that the likelihood of it happening will be extremely low.
And here’s the interesting thing…
The Appendix to this book contains a chapter entitled ‘How to Improve Fertility’ which lists all the possible supplements and pharmaceutical drugs that can significantly increase the likelihood of conception. Now, however, I would like to share one interesting fact.
Did you know that in some cases synthetic testosterone is used to boost fertility? And not just that, but also certain anabolic steroids—such as stanozolol tablets or mesterolone (Proviron)? Both of these drugs, incidentally, are analogues of DHT, which is also essential for fertility.
What I’m getting at is that high levels of testosterone in the blood (sometimes even exceeding the upper limit of the normal range) can actually be a blessing. Not a hindrance, but a help when it comes to conception. On the other hand, low levels of both dihydrotestosterone and free testosterone are bound to cause you problems.

02/06/2026

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09/01/2026

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19/11/2025

Coming soon on Amazon

13/11/2025

Enclomifene (or enclomiphene) is a relatively new drug. Essentially, it is a typical selective estrogen receptor modulator, but it lacks most of the disadvantages inherent in SERMs. However, acquiring enclomifene may present considerable challenges, because... But let's take it one step at a time.
Important notice
Get ready: there will be a lot of information, including scientific data. Unfortunately, the latter is unavoidable: this data is necessary to understand how and why the idea of creating enclomifene came from. I promise to explain everything in simple terms and as concisely as possible, without getting bogged down in unnecessary details.
Oh, yes: I should note right away that everything I write is addressed to men — after all, enclomifene was created specifically for them. However, no one is stopping women from reading this article.
What is enclomifene?
Everyone knows about a drug called Clomid (clomiphene). And many men not only know about it, but also actively use it — during post-cycle therapy, for example. But few people realize that Clomid is, in fact, a mixture of two stereoisomers of this substance: 38% zuclomifene and 62% enclomifene.
And here's what's interesting: these stereoisomers have directly opposite properties. Zuclomifene exhibits estrogenic activity, while enclomifene exhibits anti-estrogenic activity. Zuclomifene suppresses the activity of luteinizing (LH) and follicle-stimulating (FSH) hormones, while enclomifene increases the activity of both.
It turns out that enclomifene is responsible for all the benefits of clomid for men, while zuclomifene only interferes with it. If we leave only the first one and remove the second one in some way, we will get a drug that stimulates testosterone production (LG is responsible for this) and also increases fertility (FSH solves this task). At the same time, it would be free of the side effects that clomid has in abundance.
The task turned out to be not so simple, but in the end it was solved, and Repros Therapeutics introduced the drug Androxal, which contained enclomifene citrate as its active substance. All that remained was to obtain permission for its widespread sale. However, things did not go as expected.
The unhappy adventures
In 2007, the US Food and Drug Administration (FDA) refused to approve enclomifene, citing a lack of data on the drug's effectiveness. Between 2009 and 2019, additional studies were conducted, confirming that:
the use of enclomifene is safe and does not cause serious side effects;
enclomifene is indeed capable of increasing testosterone levels and can be recommended for patients with secondary hypogonadism;
the increase in testosterone levels occurs through the stimulation of LH and FSH production and activity.
Despite this, neither the FDA nor the European Medicines Agency has recognized enclomifene as an effective drug and has not granted permission for its free sale in either the United States or the European Union. That would be fine, but thanks to these same agencies, drugs with clearly unproven effectiveness and a whole bunch of side effects appear in pharmacies every year.
One can only guess at the reasons for this particular dislike of enclomiphene. I would venture to suggest that certain major players in the pharmaceutical market, unwilling to face strong competition, may have been involved. This is not the first such case, and, unfortunately, it will not be the last...
Be that as it may, today we have a paradoxical situation: enclomifene is produced and actively used with considerable success in medical practice. However, it has never been widely available for sale. More precisely, it was not available until recently, when generics began to be produced.
Weighing the pros and cons
Contrary to tradition, I will start with the arguments against the use of enclomifene. The first is that some people may not like the fact that the drug is not officially approved in either the European Union or the United States. However, if you do not live in either of those places, why do you need official approval?
The second argument against it is skepticism about generics. Although I know from my own experience that in terms of quality and effectiveness, they are often not only on par with the original drugs, but even surpass them.
The only serious argument against it is that enclomifene can increase the risk of blood clots. Yes, the risk is very small, and yes, problems can only occur in people who already have cardiovascular disease, but this argument is definitely worth considering.
Nothing else comes to mind: enclomifene has only a minor effect on the liver, very rarely causes headaches, and even more rarely causes nausea. Overall, it can be considered a fairly safe drug.
The main argument in favor of enclomifene is that it is extremely effective. There has not been a single (!) case where this drug has failed to increase testosterone levels. It is noteworthy that estradiol levels do not increase as a result of its use — neither Clomid nor tamoxifen can boast of this.
An absolutely amazing feature of enclomifene is its ability to increase the level and activity of not only luteinizing hormone, but also follicle-stimulating hormone. In other words, it helps fight both hypogonadism and infertility.
This means that enclomifene can be used in the vast majority of cases as the sole means of recovery after a steroid cycle – at least when it comes to testosterone production and fertility.
How do you use it?
Finally, some practical advice. The recommended doses of enclomifene are 12.5 and 25 mg per day. The latter is remarkably effective: in less than a month, it can achieve higher testosterone levels than those achieved with regular use of a drug such as AndroGel.
Enclomifene, unlike Clomid, has a fairly short half-life of only 10 hours. So it is best to take the drug twice a day, regardless of meals.
Above, I wrote that enclomifene is suitable for men who are trying to restore testosterone production after using anabolic steroids, but that is not the only group of people who may need this drug.
My advice to you is this: if you do not suffer from heart disease, try enclomifene. It will definitely help you solve your testosterone and fertility problems, if you have them. No better remedy has yet been invented to solve these two problems at the same time.

20/10/2025

I am planning to publish a book on selective androgen receptor modulators and peptide drugs in 2026. As I work on it, I will gradually introduce you to its contents, posting about one chapter per month. This one is dedicated to a drug known as Acadin, AC-262, or AC-262536. It is particularly relevant because I have been receiving a lot of questions about this drug lately.
Necessary caution
When purchasing selective androgen receptor modulators (SARMs), you do so at your own risk. All of these drugs are experimental — none of them have yet been launched into commercial production. This means that you cannot be completely sure of the effectiveness or safety of the selective modulator you are purchasing.
What's more, since all SARMs are produced exclusively illegally, you cannot be sure of the quality of your purchase — that the product you bought contains exactly what you paid for, and in the quantity stated.
What is AC-262?
If none of this scares you, then let's get started! Let's find out what AC-262536 is: this is the official name of the drug, but I will use its abbreviated form — AC-262.
The drug was developed by Acadia Pharmaceuticals, hence the name Acadine (spelled with one «c»). It was created specifically to combat prostate cancer; AC-262 should also help in the treatment of Alzheimer's disease.
The drug is currently in the research stage — so far, it has only been tested on laboratory animals. Human trials are still a long way off, so the effectiveness and safety of AC-262 for humans can only be judged based on the personal experience of those who have taken it.
It can be said with absolute certainty that AC-262 has a relatively low affinity for androgen receptors (AR): it lies in the lower range (1-10 nanomoles) and is approximately 5 nM. However, even when bound to AR, the AC-262 molecule does not necessarily activate it: on average, 66% of molecules are capable of doing so (each testosterone molecule necessarily activates AR).
On the other hand, the drug does not activate any other receptors, does not convert to estradiol or dihydrotestosterone, and does not bind to AR in the prostate (in fact, this property was inherent in it from the outset), skin, seminal ducts, or nerve fibers. In other words, AC-262 has minimal side effects.
What can you expect from the AC-262?
Moderate increases in muscle mass: experience with AC-262 shows that by consuming sufficient amounts of protein and other supplements, as well as training properly, it is possible to increase muscle mass by 2-2.5 kg in eight weeks.
I tried comparing AC-262 with other SARMs, and here's what I found
In terms of muscle mass gain, the drug is significantly inferior to RAD140, but superior to LGD-4033.
In terms of strength, drive, and recovery speed, AC-262 is significantly inferior to S-23.
Don't expect outstanding results in fat loss either: AC-262 can only slightly increase the rate of metabolic processes, but it has no effect on lipolysis — it's not like Ostarine (MK-2866).
But when it comes to side effects, AC-262 surpasses all of the above drugs: it can be considered almost the safest SARM (perhaps with the exception of S-4).
Another positive feature of AC-262 is its ability to suppress cortisol activity and thus prevent protein breakdown. In this respect, it is better to compare it not even with SARMs, but with an anabolic steroid such as stanozolol.
Weighing the pros and cons
AC-262 has been found to have a rather unpleasant side effect: prolonged use can trigger a heart attack or even a stroke. Apparently, this is why the drug has not yet been tested on humans.
Another unpleasant effect associated with taking AC-262 is quite severe headaches. In addition, joint pain is possible, albeit mild. So, those who have old injuries or chronic joint problems are better off not taking AC-262.
The drug's minimal impact on the body's own testosterone production is a plus. So, you can use it during post-cycle therapy to fight muscle breakdown.
Finally, let's talk about AC-262 dosage. In any case, it is worth starting with 10 mg per day — this will reduce possible side effects to an absolute minimum. 20 mg per day is for those who know what to expect from AC-262; this dosage achieves the ideal balance between effectiveness and safety.
30 mg is for athletes who value effectiveness over safety. With this dosage of AC-262, you will definitely experience significant suppression of your own testosterone production.
In any case, you should not take the drug for more than 4-6 weeks in a row; eight weeks is the absolute maximum. I am talking about people who do not have serious health problems. Those who suffer from cardiovascular diseases should not even consider AC-262.

13/09/2025

I have probably never written such a short book before, and I doubt I ever will again. Nevertheless, working on it proved to be no less difficult than working on a substantial, voluminous work — I had no idea there would be so many difficulties.
First of all, the thing is that everyone understands the word «prohormones» to mean whatever they want it to mean. That's why drugs that are completely different in origin are lumped together — not to mention their properties, behavior, effects on the body, and so on.
Secondly, information — there is practically none. There are very few studies that can really be relied upon; most articles are written in collaboration with manufacturers of «prohormones» (I put this word in quotation marks for a reason) — which means they are not particularly truthful.
Thirdly, availability. Yes, some prohormones (I mean real prohormones) can be purchased, but, first of all, with much greater difficulty than, for example, SARMs or even anabolic steroids. Second, the price: when you look at it, the desire to even try androgen precursors noticeably weakens and then disappears altogether.
Difficulties, difficulties, difficulties... I tried to overcome them, and what I came up with can truly be called the most comprehensive guide to the use of prohormones. I tried to proceed systematically — from limiting the range of substances that can be considered prohormones, through the history of their creation, to the consideration of specific drugs.
We will talk about the effectiveness of prohormones and about drugs such as prosteroids. But let's start with the answer to this simple question: how does testosterone synthesis occur? And then we will move on to the formal definition of prohormones.
the book is available on Amazon:

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09/09/2025

Coming soon on Amazon!.

22/08/2025

What you are reading now is the most comprehensive guide to planning short steroid cycles. In fact, it is the only guide of its kind. So you definitely made the right choice by paying attention to it.
Why did I decide to write it? It's simple: many fans of the bulging muscles of athletes would love to try anabolic steroids — drugs that provide a significant advantage on the path to the desired physique. But fear holds them back, because there are so many unpleasant things said about steroids. If only it were completely safe...
So, it turns out that using anabolic steroids can be safe after all! Maybe not 100%, but definitely 99%. You just need to be smart about it and not go overboard. Short cycles are the best way to go for a sensible and balanced approach.
Interestingly, I didn't realize this right away: my first experience with short cycles was a complete disappointment. I even swore never to go back to them, only to break my vow a month later and try to figure out what could be improved.
A lot of time has passed since then, and I have completed countless short cycles; I have learned how to plan them correctly and get the most safety and effectiveness out of them. I want to share all this knowledge with you in this book.
And one more thing: in the first sentence, I wrote «steroid cycles». In fact, I am not going to limit you to the use of anabolic steroids alone — there are many other drugs that are not only suitable for use in short cycles, but even make them more effective.
Well, it's time to get down to business! This book will contain a lot of practical information — almost all of it, in fact. But I would still like to start with a theoretical explanation of short cycles.
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