Test prop works by making the muscles hold onto nitrogen, which means the muscles hold onto more protein. Holding onto proteins means better usage of energy, which subsequently means increase in muscle size and strength. Test prop has the ability to stop muscle wasting so you keep all of the muscle mass you worked hard at getting. There is no muscle wasting from the glucocorticoid hormones and red blood cell production is increased, which subsequently allows more oxygen to come in the body. Higher oxygen level in blood cells mean that you will not tire as fast and as much, what will than aid in recovery times as well.
This is a great question that, unfortunately, cannot be answered in just a couple hundred words. There are important issues that focus on educating one's self prior to embarking on such a course of action, particularly the downsides of using steroids – the side effects, the proliferation of fake gear, getting off of them, getting blood work done, etc. And, the fact that buying, selling and transporting them is (in America) still a felony, not to mention banned by all sports federations. All very important salient issues that require a lot of space to do justice.
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