There is simply no other exercise, and certainly no machine, that produces the level of central nervous system activity, improved balance and coordination, skeletal loading and bone density enhancement, muscular stimulation and growth, connective tissue stress and strength, psychological demand and toughness, and overall systemic conditioning than the correctly performed full squat.
Mark RippetoeAccumulating injuries are the price we pay for the thrill of not having sat around on our asses.
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 RippetoeYou 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 Rippetoe