I use to do deadlifts wtih bad tachnique, a rounded back as i was coming back. This is the most common mistake, deadlift like your doing a squat, head up back braced, and drive with your feet first. A test i do to determine if the weight is too heavy is get into the starting position, and look into a mirror to the side. I try for a half rep, and if it is too much, my back will automatically round, my nervous system calling it in to help my legs. I lower the weight until i can do a perfect rep, meaning a straight back.

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