Empirical and anecdotal evidence clearly 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. 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. The wiser athletes put every bit of knowledge they have into designing their cycles.