Figure 1: Axial load, flexion angle, anterior-posterior load, and internal-external torque applied during the simulation of knee bend, stair ascent and descent, sitting and rising from a chair, and level walking. The coordinate system from ISO 14243-1:2009(E) is applied [23]. First peak of the axial load for level walking, stair ascent and descent (coincident with contralateral foot lift). Increased axial load for knee bend corresponds to descent. Minimum axial load for sitting and rising from a chair indicates resting on the chair after sit-down. The timeframe was adapted from previously published data [59].