Fig. 5. Mean ankle joint moment (A) and knee joint moment (B) of 10 subjects of one full descending stride cycle for standard stair descent (solid lines) and stair descent with 20% extra body weight (dotted lines). Vertical lines indicate foot-contact times [lift-off (LO) right, touch-down (TD) right and LO left] for both conditions, whereas 0 and 100% of the stride cycle indicate TD of the left (analyzed) foot. For clarity, only the negative s.d. of standard stair mass condition are presented.