When I am working with my clients especially with weights I use the term "hip hinge" quite often. Whenever we do weight work such as bent over row or dead lifts or reverse flies we work in a position such that we are working against gravity making sure the appropriate muscle is working. However, one thing I want everyone to avoid is bending over such that they are bending through the lumbar spine or even rounding through the upper back and shoulders. Either one of those positions is not advantageous even without weights in hand. Either one adds stress to the spine. It is important to maintain a good neutral position with the spine and then bend forward from the hip not from the back.
With daily living activities, the same guidelines apply. When brushing the teeth, avoid bending over through the lumbar spine or upper back. Hip hinge. Always protect your spine. If you are not sure what I am talking about, check out the youtube video at
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