Periodization is the planned manipulation of training volume and intensity throughout a series of specific training phases or cycles. Periodization is an application of the principles of progressive training - you vary your repetitions, sets, weight and intensity during each cycle - and is a method used to make continual improvements in performance throughout the course of a set time frame. If you follow the same workout for any length of time, the body soon adapts to the constant load and your gains diminish. However, by structuring your long-term training goals in a number of training cycles, you will be able to make continued gains in strength, power and endurance, and you will also avoid overtraining and injuries