I've decided to part from my usual split and give HST training a go. Before I start I have a couple questions.

1) Are you supposed to do a warm up set for EVERY bodypart (legs,chest,back,traps,etc)

2) Are you supposed to change the exercises each time you train (mon. legs-squat, leg curl. wed. legs-leg press, leg curl) OR keep doing the same exercises for one week then change them the following week?

Any advice greatly appreciated!