Bending with a Neutral Spine
When you bend over or lean forward to brush your teeth or wash your face at the bathroom sink or do other similar activities, it is very helpful to use a movement known as the hip hinge. The hip hinge is a more normal movement that creates a deep crease through the groin region and it significantly reduces the strain on the spine.
To do the hip hinge, bend your knees slightly, and while keeping your back straight from the hip to the shoulder with no bending or rounding at the waist and as lengthened as possible in the neutral spine position, stick out your tailbone behind you to bend forward from the hips. Your back muscles will need to be retrained to learn how to use the hip joint and the strong buttock muscles along with the leg muscles to allow you to bend and lean over with less strain on the spine. This movement will feel awkward at first but it will become more comfortable once you master the technique. Eventually, it will feel normal to bend this way without even thinking about it.