I have started many people at 400, 450, or 500#, if that's the appropriate weight to start them at. I think you are reading too much into what this individual said. It seems she made a blanketed, antiquated statement that seems to imply the simple fact of "deadlifting over 500#" was dangerous, with no other qualifying statement. 99% of the acute back injuries occur outside of deadlifting, therefore, one could say virtually any activity is dangerous if it is the activity you were performing when the onset of pain occurred. Hell, I've dealt with probably a half dozen patients with acute, severe back or hip pain that occurred during intercourse. I would personally take that to the grave with me, but, it may just be the toxic masculinity talking.
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