Glenn Pendlay
most people get stuck in a rut in training. bodybuilders for example often get stuck in the one time per week per bodypart rut, and that determines how many sets they do, the intensity they use, etc. since they are not going to change frequency, they end up not changing much over time.
you have to continually challenge your body with things it is not adapted to... and by the way i think westside does a good job of this. HOWEVER, much of westside is based off a sort of linear scheme, no matter how much louie says he doesnt agree with that sort of thing... in westside you have "waves" of a sort, where the volume goes down and the resistance goes up, but for the most part the overall stress on the body stays the same week after week (with the exception of circa-maxima), stays the same or gradually goes up as you accomodate yourself to more and more training.
it is my belief that the overall stress on the body must change week to week, and periods of very high stress must be incorporated periodically into training, periods of stress so high that you can only keep it up for between a week to 3 weeks, any more than this and you would run yourself into the ground. research shows that these periods of very high stress have a powerfull effect on the body, making it more able to handle subsequent high stress training up to a year after the initial loading period.
once you are no longer a beginner, your body simply does not respond well to "average" training... people make progress still, but often it is because they gradually up the training stress to a point that is result producing without any clear plan... and this leads to lost training time because the buildup to this required stress level takes too long, and then often the high stress levels are continued for too long, leading to high performance followed by lower performance for a while becasue of inadequate restoration.
if you allow from the start that that you are going to have to take your body to the edge at least once every training cycle, you can plan when you do it, and how long you have to recover from it, you can have shorter training cycles, more precisely timed peaks, generally more progress.
the best system to my knowledge that has been documented to work in this manner is an 8 week training cycle where weeks 3 and 4 are high stress, weeks 2 and 5 are normall stress, week 1 is low stress, and weeks 6,7, and 8 are peaking weeks.