Some bodybuilders and athletes use trenbolone esters for their muscle-building and otherwise performance-enhancing effects.  Such use is illegal in the United States and many other countries. The DEA classifies trenbolone and its esters as Schedule III controlled substances under the Controlled Substances Act .  Trenbolone is classified as a Schedule 4 drug in Canada  and a class C drug with no penalty for personal use or possession in the United Kingdom .  Use or possession of steroids without a prescription is a crime in Australia .  The infamous "duchess" cocktail administered to Russian athletes at the Sochi Winter Olympics consisted of oxandrolone , a metenolone ester, and a trenbolone ester. 
Injectable steroids are injected into muscle tissue, not into the veins. They are slowly released from the muscles into the rest of the body, and may be detectable for months after last use. Injectable steroids can be oil-based or water-based. Injectable anabolic steroids which are oil-based have longer half-life than water-based steroids. Both steroid types have much longer half-lives than oral anabolic steroids. And this is proving to be a drawback for injectables as they have high probability of being detected in drug screening since their clearance times tend to be longer than orals. Athletes resolve this problem by using injectable testosterone early in the cycle then switch to orals when approaching the end of the cycle and drug testing is imminent.
Testosterone Propionate Many consider propionate to be the mildest testosterone ester, and the preferred form for the dieting/cutting phases of training. Some will go so far as to say that propionate will harden the physique, while giving the user less water and fat retention than one typically expects to see with a testosterone.
During a typical cycle one will see action that is consistent with a testosterone. Users sensitive to gynecomastia and water retention may therefore need to add an anti-estrogen like Arimidex, Femara or Aromasin. Those particularly troubled by gynecomastia may find that a combination of Nolvadex and Proviron works especially well at preventing/halting this occurrence.