Bodybuilding is about training muscles, not lifting weights. You use the
weights and proper technique in order to target certain muscles or muscle
groups. Weights are just a means to an end. In order to do this effectively,
you have to isolate the muscles you are targeting. Remember how
often you have been told to lift something with your legs and not your
back? This technique deliberately brings as many muscles into playas possible
to protect you from injury. This makes sense if you are a piano mover
or a construction worker. But the task of the bodybuilder is very different.
You don't want to make the lift easier, you want to make it harder! You
want the target muscles to do all the work, with little or no help from other
muscle groups.

Good technique helps you to do this. So does choosing the right
amount of weight. Once you are using a weight that is too heavy for your
target muscles to handle, your body will automatically call other muscles
into play. That's the way your nervous system is designed. So the fact that
you can lift a weight doesn't mean you are doing the exercise correctly. You
also need to choose a weight that ensures that the target muscles alone are
responsible for lifting that weight.
How do you do this? One way is to start out lifting very light and concentrate
on how the muscles feel during the movement. Gradually increase
the weight. But if and when you get to a point where you can no
longer feel the muscles working as they did when the weight was lighter,
chances are you are working too heavy and need to back down a few
pounds until that "feel" is reestablished.

This post has been edited by arekey: Nov 25 2010, 11:41 AM