By adding 400mg per week of nandrolone to a testosterone cycle or a dianabol cycle, you’ll be able to increase your overall steroid dosage, without increasing the side effects. For example, a bodybuilder taking 500mg Sustanon 250 per week, who felt he needed more power in his cycle, would find himself with more side-effects if he were to just take more of the same testosterone. Since testosterone aromatizes at an increasing rate at higher doses, there would be an exponential increase in the likeliness of gynecomastia and water retention if more testosterone was added weekly. When adding nandrolone decanoate to the same testosterone cycle, you are increasing the total amounts of steroids your body is receiving every week. However, you are not adding anymore viable substrate for undesired enzymatic reactions from aromatase and 5-reductase. In simple terms, you use more steroids without more side effects.