Weight-bearing or weightbearing refers to the act of putting the structural load of one's own weight onto one or more parts of the body. In biology, it usually refers to a terrestrial animal supporting the position and posture of its own core against gravity using limbs, legs or other appendages. In bipedal animals such as humans, weight-bearing is predominantly performed by the lower limbs.
In clinical medicine, particularly the field of orthopedics and physiotherapy, the term is used to describe the amount of weight a patient can safely put on an injured body part. Generally, it refers to a leg, ankle or foot that has been fractured or upon which surgery has been performed, but the term can also be used to refer to resting on an arm or a wrist. In general, it is described as a percentage of the body weight, because each leg of a healthy person carries the full body weight when walking, in an alternating fashion.[citation needed] For example, after surgery on the hip, leg, ankle or foot, it is of the utmost importance for recovery to get the right amount of weight-bearing when moving around with crutches or frames in order to prevent accidental bone displacement and malunion
The grades of weight-bearing for each phase of recovery will be determined by the surgeon. The Anti-Gravity Treadmill can allow testing of weight bearing by lowering effective body weight in 1% increments from 100 to 20% of body weight.