How Steroids Work
Anabolic steroids are tiny molecules made up of carbon atoms arranged in a ring. Their size and atomic composition allow them to easily enter cells and the cell’s brain, called the nucleus. There they tell the cell to make different proteins by binding to small molecules called receptors.
When the anabolic steroid attaches or binds to the receptor, the cell knows it’s time to change the proteins it produces. Protein isn’t just important in your muscle-building diet – all of your cells make protein and are essential for structure and function. Anabolic steroids change the amount of a type of protein produced.
Anabolic steroids must bind to receptors in the skeletal muscle and the muscles of the arms and legs that we use to lift, in order to cause changes in protein production. In muscle cells, anabolic steroids enter the nucleus and change the number of certain proteins produced.
The proteins involved in muscle building are upregulated, which means that steroids “increase” the number of them produced. The proteins involved in muscle breakdown are downregulated, which means they are produced less.