Bending is the act of repositioning one’s body from a straight, upright position, down towards the ground by inclining one’s torso forward and lowering one’s knees. A bending motion may also be accompanied by a reaching of the arms, in the case of one bending down to pick something up off of the ground. Bending down may also be done as an act of submission or reverence in some cultures, as when one bows to another or bends down to pray, or, in the case of ducking down, one may bend their body so as to avoid detection or being physically struck by something.
To prevent knee and back pain when bending over, the bending should only be happening from the knees and hips, not the waist. Further, avoid twisting from the spine to reduce the risk of fractures and strains. To treat current pain, over-the-counter medication and nonsteroidal anti-inflammatory drugs (NSAIDS) along with rest are recommended.
Many factors may contribute to dizziness after bending over. You may be dehydrated, have low blood sugar, and have poor circulation, anemia, a panic attack, inner ear problems, or hypothyroidism. The dizziness may be a side effect from the medication being taken, or other factors such as hormonal changes may be the root cause.
A bending moment occurs in a structural element when an external force, or moment, is applied to the element which causes it to bend. For equilibrium, the moment from the external forces need to be balanced by the moments from the internal forces. The resultant internal couple is the bending moment.