An elliptic motion exercise machine includes a frame, on which a
reciprocating motion mechanism, a circular motion mechanism and two
linking members are provided. Two parallelogram linkage mechanisms are
movably mounted on the frame and connected to the linking members. Two
foot panels are fixed on the parallelogram linkage mechanisms
respectively. The parallelogram linkage mechanisms keep the foot panels
in fixed slops in the entire motion, such that when an user stands feet
on the foot panels and exerts the foot panels, toes of user's feet moves
in a speed that is substantially identical to that of use's heels.