Empirical and anecdotal evidence clearlv show that steroids are most effective and safest when they are used in a logical sequence referred to as a cycle. The term cycle is commonly used by athletes to refer to the time they are on steroids.
When two or more anabolic steroids are used at the same time, it is called "stacking". The time period in which a body builder or person uses these anabolic steroids is called a "steroid cycle". Athletes stack anabolic steroids with other drugs to help maximize the results of their cycle. It has been shown that steroid stacks can cause an even more dramatic effect on the users muscle, than when taking only one type of steroid.
Different anabolic steroids have different effects on the body, so when two different steroids are introduced (stacked) together, often times you will see the muscle gaining side effects of each different steroid! These steroid cycles may also include taking one particular anabolic steroid at the beginning of the steroid cycle and finishing up with a different steroid at the end, to better enhance the users desired result. Steroid stacks have been used for years and have proven to be a more effective way to build quality muscle than when using only one type of steroid. One very important thing to note: when using more than one anabolic steroid in a stack or cycle, the risk of harmful side effects increases. Within a steroid cycle, the users will often stack other non-anabolic drugs into their program to help minimize these steroid side effects.
An average on cycle is usually from 6 to 12 weeks. An average off cycle, which is the time off of the steroids, should be at least 10 to 12 weeks. This pattern is needed to minimize side effects associated with long term steroid use. It is felt that doing just 2 cycles a year is best to keep side effects to a minimum. In the off cycle period, the user is allowing the body to restore its natural hormonal patterns and to recover from any stress that occurred during the cycle.
Cycling steroids is also important to insure their effectiveness. If a person stays on a steroid for too long, receptor sites will fail to recognize it. This attenuation is not experienced if cycles are done properly. Some evidence supports keeping cycles fairly short; about two months in length or less. Recent evidence has shown that receptor down regulation, which is a decrease in the amount of a steroid being picked up by a cell, occurs in as little as 3 weeks. Also shown was that the positive nitrogen balance, a primary anabolic indicator of a steroid, will not exist if the dosage is not continually increased. This is also due to the fairly rapid and progressive loss of sensitivity of receptors to exogenous steroids. With cycles of excessive duration, the receptor site gets so over stimulated by exogenous steroids, that it can even fail to respond to endogenous androgens. A person in this state could use huge dosages and still not get any results. This explains a great deal of logic behind some of the cycle patterns commonly used today. The wiser athletes put every bit of knowledge they have into designing their cycles.