You do not need to do many different exercises to get strong - you need to get strong on a very few important exercises, movements that train the whole body as a system, not as a collection of separate body parts. The problem with the programs advocated by all the national exercise organizations is that they fail to recognize this basic principle: the body best adapts as a whole organism to stress applied to the whole organism. The more stress that can be applied to as much of the body at one time as possible, the more effective and productive the adaptation will be.