Estrogen “Control” was paramount for health and result potential reasons. High/prolonged circulating estrogen levels could have negatively affected the heart and other organs due to excess fat deposits and water retention. As you know, most severe water retention during anabolic steroids phases is due to estrogen and the resulting hormonal production increase of aldosterone.
Elevation of aldosterone affects the body’s water table by altering electrolyte balances favoring sodium retention. Since sodium regulates extracellular (outside the cell) water and potassium regulates intracellular water, an imbalance favoring sodium results in extra water in the vascular system and under the skin. This is the reason that some athletes look like “Bloat Boy” and have very high blood pressure.
It is important to remember that electrolytes such as sodium and potassium regulate the electric charges for flow of water molecules across cell membranes and are an intricate part of the sodium-pump mechanism that allows goodies like nutrients and creatine to actually enter the muscle cells.