The present invention relates to a standup exercise apparatus that simulates lateral climbing with arm exercise. More particularly, the present invention relates to an exercise machine having separately supported pedals for the feet and arm exercise coordinated with the motion of the feet. Each pedal follows a separate elongate curve with lateral movement. As one pedal moves downward on the inside portion of one pedal curve, the other pedal moves sideways upward following the outer portion of the other pedal curve. A pair of cranks rotate in opposite directions when driven by the pedal movement. The orientation of the pedal curves is adjustable to exercise leg muscles differently. Arm exercise is coordinated with the foot pedal movements.