Testosterone can be administered parenterally , but it has more irregular prolonged absorption time and greater activity in muscle in enanthate , undecanoate , or cypionate ester form. These derivatives are hydrolyzed to release free testosterone at the site of injection; absorption rate (and thus injection schedule) varies among different esters, but medical injections are normally done anywhere between semi-weekly to once every 12 weeks. A more frequent schedule may be desirable in order to maintain a more constant level of hormone in the system.  Injectable steroids are typically administered into the muscle, not into the vein, to avoid sudden changes in the amount of the drug in the bloodstream. In addition, because estered testosterone is dissolved in oil, intravenous injection has the potential to cause a dangerous embolism (clot) in the bloodstream.
The fact is that anabolic steroids do present various health risks – they are not without their faults and potential risks, as with anything. However, the context under which they are utilized presents a vast difference in how much of a risk is being taken. Responsible and judicious anabolic steroid use among healthy adult males is a significantly different situation in comparison to anabolic steroid use among children, teenagers, and females. Within the context of healthy adult male anabolic steroid use, the associated and proposed risks plummet by a massive degree, and from what we already know from studies referenced above, the average anabolic steroid user is in fact not teenagers and nor are they athletes, but are healthy adult males in the median age range of 25 – 35 years of age. Other more recent studies have also supported this fact among steroids statistics, where a 2006 study that surveyed 500 anabolic steroid users found that almost 80% of these users were not competitive athletes or bodybuilders but instead average adult physically active males  . Furthermore, the majority of anabolic steroid users are short-term users that do not engage in lifetime use (either in cycles or constant use), and that the rate of actual lifetime use among anabolic steroid users was found to be % for males, and % for females5. What this means is that only % and % of all male and female anabolic steroid users respectively will engage in lifetime use (mostly via subsequent cycles), while the rest will only utilize anabolic steroids once or a handful of times during their life.
It could be argued that aromatization is a non-issue, as an . could always be employed to counter estrogen conversion. This is true, but I believe there is a simpler way to go about it. In my opinion, the ideal pre-contest MPD cycle should consist of a low dose of testosterone propionate (150-200 mg/week), as at least some estrogen is needed to maintain a healthy looking skin tone. This should be combined with 2-3 other anabolics; preferably 1-2 oral anabolics and 1-2 injectables anabolics. Some good examples of orals include: Anavar, Epistane, and Turinabol. As for injectables, most people usually find the following drugs to be compatible: Primo, Boldenone, and Dihydroboldenone (1-testosterone).