I started to use a vartiation of the 5 X 5 jsut before I injured my shoulder a month ago. Basically what I did was only use the 5 X 5 for power movements such as any pressing exercise for chest, 2 out of my 4 row or pulldown exercises for back, 1 of my 3 exercises for bi's, etc......
IMO, you shouldnt just take your normal routine and make all the exercises 5 X 5. I think thats too much.
Also, while incorporating the 5 X 5, on the exercises where I didnt use it, I still went pretty heavy but kept the reps in the 8-10 range.
It was working quite well, I hit personal bests in every exercise that I used the 5 X 5 but its tough on the body if your really doing it hardcore. Id say that if one is going to use the 5 X 5 or a variation of it, make sure you are eating tons so that your joints can fatten up a little to handle the increased weight load.
Personally, Im going to go back to it next week when I start training again from my injury but Im going to use more of a 5 X 6. 6 being the reps.
