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.
Lack of estrogenic properties make trenbolone popular among athletes who want to lose fat and to avoid fluid retention. “Tren” gives us the high androgen content needed to make the hardness and muscle definition. Giving the hardness is not the only advantage of this steroid, because he also is -building properties of this steroid often compared with the effect of such powerful drugs such as testosterone or Dianabol, which in this sense are very similar, but they cause fluid retention. Lack of estrogenic characteristics affect the growth of muscle mass. Many people use this drug in the final interesting fact is that the friction is often recommended as an additional tool for building muscle. If you use it on their own, it is not a strong substance. If it is taken without another estrogenic steroid, results are positive, there is a tissue growth that is accompanied by increased hardness and fat loss. Although, maybe he is not as strong as most of the estrogenic steroids to build up, which only increase the weight, I think we can safely say that trenbolone increases better than nandrolone, and is the best of all anabolic steroids neestrogennyh.