If you have read bodybuilding/fitness magazines at all in the past few years, then you have no doubt heard of a theory called periodization. The theory is basically this; you need to give your body periods of varied intensity as far as weight training goes. I think this is a good theory. As we talked about in Splits and Frequency, and Overtraining, your body needs recuperation from training. It has been said many times, exercise is only a stimulus for muscular gains, the gains themselves come from rest, recuperation, and Nutrition. However, this usually refers to short term rest and recuperation, while the Periodization theory is actually addressing more long term effects. After a couple of months of high intensity training, your system could use a bit of a break. Adaptation and muscular growth come at a price to your physiological system. There is more involved in this theory, however, than merely recuperation. Your muscles respond to different intensities in different ways. If you always work your muscles in the same intensity range, then you are limiting the response that you will get. Heavy weight is definitely useful, (and necessary), but lighter weight also has its benefits. But before you get the wrong idea, you don't get to make it a cakewalk. That is, you still need to exercise hard, just use higher reps, and lower weight for a while.

I think a great example of periodization is a method I like to use. Do a full body workout for two weeks, followed by a two way-split for roughly three weeks, and a four way split for a month after that. Finish up with two weeks of circuit training and I'm willing to bet that you will see great results.

A lot of "experts" like to talk in terms of "%of1RM". That is, Percentage of One Rep Max. A lot is made of figuring out exactly what the maximum weight is that one can use to perform one repetition of a given exercise, (1RM). Then, your working weight for that exercise is advised to be a certain percentage of that "magical" 1RM, (usually about 70%-80%). To heck with all that. I

ntensity could be defined as Work/Time, or a specific amount of work, performed in a specific amount of time. For all of us "real" people, however, it will suffice simply to equate intensity with amount of weight lifted. I believe that performing in the proper range of repetitions, as described in Sets, Reps and Weight, is the best gauge of intensity.