[quote]echelon101 wrote:
Assuming that perfect technique is employed in a full squat, as per Rippetoe’s SS what is the difference between the force acting on the quadriceps between a smith and free squat?
[/quote]
You’re squatting the same weight, but the smith only allows moving in one dimension, which reduces the employment of stabilizer muscles.
Bottom line: Do your squats free form and steer clear of the Smith machine.