Steroids mimic testosterone in the body, which means they encourage the body to lay down protein, increasing muscle mass. Steroid use common with bodybuilders and people involved in certain sports. Steroids are often injected into the body intravenously. There are many other types of steroids, such as creams and medications for infections, which are less likely to be abused in comparison to anabolic steroids. Anabolic steroids are considered illegal “doping” by many different athletic associations, from Olympic athletes to baseball (MBL) and football (NFL) players.