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.
Mark RippetoeThe full-range-of-m otion exercise known as the squat is the single most useful exercise in the weight room, and our most valuable tool for building strength, power, and size.
Mark RippetoeSince the trainee is both inefficient and unadapted, only a few basic exercises should be used, and they should be repeated frequently to establish the basic motor pathways and basic strength.
Mark Rippetoe