At the end of an hour, none of the original dose of testosterone can be detected in the body. Medicinal chemists began to alter natural testosterone in an attempt to make drugs that would work like testosterone but last long enough in the body to have an effect. All anabolic steroids in use today are variations of one of those three changes to the testosterone molecule. These chemical classes of anabolics are taken by different routes and have different side effects on the body. For convenience, they will be classified here as oral or injectable steroids.
Athletes usually experiment with oral anabolics at first.
An athlete will usually continue to use oral drugs even when he or she begins using injectable steroids. Many athletes and trainers also believe that it is necessary to use oral and injectable steroids at the same time, in certain patterns. Chemically, the injectable steroids are better tolerated by the body than the oral steroids. Long-term steroid abusers begin to use them for this reason. However, injection of any substance creates its own risks and health problems.