Starting Strength vs. Powerlifting
Mark Rippetoe laid out an impenetrable argument in Starting Strength for getting strong. Perform exercises that:
1) use the most muscle mass,
2) use the greatest effective range of motion, and
3) use the most weight possible (with proper form).
Most powerlifters would subscribe to Rip’s first and third criteria. However, they would NOT subscribe to the 2nd criterion. Instead of lifting for the greatest effective range of motion, they lift weights over the shortest legal range of motion required by their federation.
This is a critical distinction between powerlifting and Starting Strength. It is why we see powerlifters perform ultra-wide-stance squats, sumo deadlifts, and ultra-wide grip bench presses with huge arches where they touch their bellies rather than their chest. All of these “form tweaks” exist for one reason: they decrease the range of motion, allowing the powerlifter to lift more weight in a competitive setting.
Powerlifters perform the competition lifts to get the highest total they can, whereas Starting Strength focuses on getting people generally strong. The differences may be subtle, but they result in different executions of the basic barbell lifts based on the way we use moment (rotational) force.