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(etothepii @ Sep. 12 2007,13:39)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">I used the advice of a student of mine and verified it with a coworker who is also a high school football coach (former college player too). My bench seems to be the right height, legs slightly above parallel when I sit. My feet are in front of me, not straddled. I sit, do a slight rock back, then forward and stand up. I keep the core solid as to prevent haunching over and bending the spine.
To test the waters, I first did an unloaded bar -- just to get the feel of what would be happening. Then did 135 lbs -- easy. Then 205 -- easy. Then 225, my atg 5rm -- easy, then upped it to 255. Felt heavy on my shoulders, but the squat was still very easy. I'm guessing I can get to 300+ in a few workouts.
I'm curious to see how that will effect my atg when I go back to it.</div>
There is no "right" height for a box squat, it can be anything from high (above parallel) to low (below parallel), within reason.
Also, bear in mind I'm defining parallel as the following, where the crease of the hip falls below the top of the knee:
Of course, most people aren't squatting this low, either because of ego (every inch past some point becomes a mile, and many people would probably have to drop their squats by 100+ lbs by going this low) or not knowing better.
But yah, even in the context of a box, there is no "box height" that is universal. In principle, you'd want to box squat to at least parallel, which would probably imply a height of, say, ~12-15" depending on limb lengths and so forth for an average joe. The average bench for bench presses is usually well above this height.