Testoprop-100 (Testosterone Propionate) is the shortest-estered testosterone product available. There are some advantages and disadvantages to this. The major disadvantage is that users will have to inject Test Prop at least every other day throughout its cycle to get proper results. The advantages, however, are less bloating and water retention that longer-estered products and because there is less ester in each vial, there is more actual testosterone per injection, which brings better results.
Testosterone is the male sex hormone responsible for many of the physical and emotional traits of men. It creates the deeper voices, sex drive, aggression and, of coarse, larger muscles in men. Testosterone makes the muscles retain more nitrogen, which in turn makes the muscle synthesize proteins better, producing larger muscles.
The downside to testosterone steroids is that they aromatize, or turn into estrogen, in the body. When the body has too much estrogen it begins to take on female characteristics gynocomastia, water retention, fat gain, loss of sex drive and testicular shrinkage are all most certain side effects of taking testosterone and letting it aromatize in the body.
Testosterone propionate is a commonly manufactured, oil-based injectable testosterone compound. The propionate ester will slow the rate in which the steroid is released from the injection site, but only for a few days. Testosterone propionate is therefore much faster acting than other testosterone esters such as cypionate or enanthate, and requires a much more frequent dosing schedule, in order to maintain stable blood levels. While cypionate and enanthate are injected on a weekly or bi-weekly basis, propionate is usually injected every second. The propionate ester can be very irritating to the site of injection. In fact, many sensitive individuals choose to stay away from this steroid completely, their body reacting with a pronounced soreness and low-grade fever that may last for a few days.
Those who do not mind frequent injections will find propionate to be quite an effective steroid. As with all testosterones, it is a powerful mass drug, capable of producing rapid gains in size and strength. At the same time the buildup of estrogen and DHT (dihydrotestosterone) will be pronounced, so typical testosterone side effects are to be expected. 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. Realistically however, this is nonsense. The ester is removed before testosterone is active in the body, and likewise the ester cannot alter the activity of the parent steroid in any way, only slow its release. We can say that propionate might be the favored testosterone among female bodybuilders (for those who insist on testosterone use), as blood levels are easier to control with it compared to other esters. Should virilization symptoms develop, one would not wish to wait the weeks needed for testosterone concentrations to fall after a shot of enanthate for example.