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Beginning (gram on left) – Use a low bench, keep knees bent and stay close to the bench. Dip as low as you can then straighten back up.
Intermediate (mom in middle) – Use a low bench, keep knees bent or try and straighten if you can. Dip up and down.
Advanced (me on right) – Use a higher chair, straighten legs out away from the bench and dip all the way down to 90 degrees and back up.