There is an attitude among some part-time body builders that someone who hits the
gym and goes straight for the heaviest weights is a "hero", a real above and beyonbd the call of duty guy. This is a fairly dumb attitude to take because, without warming up and down, a body building routine will do very little for you. In actual fact, going for the big weights before you are ready to lift them will destroy any of the good work that you do. A little bit of thought is required before you really go for it.
Warming up is a big part of a body building routine. Generally taking the form of some stretches before you get into the meat of the routine, it means the muscles will be in shape to handle the harder work you are about to put them through. Picking up weights puts a strain on the muscles, and through this work they will become stronger. But going straight from resting mode to hard work will only result in damage being caused. The preparation involved in a body building routine is as important as the exercise itself.
As much as some people may smirk at the idea of going about things by the book, you have to think about what you want to achieve through a body building routine. If it is about getting into the best shape possible, there is no way of achieving this without observing the rules. You will simply do more harm than good.