The combined arm–leg (Cruiser) ergometer is assumed to be a relevant testing and training instrument in the rehabilitation of patients with a lower limb amputation. The efficiency and submaximal strain have not been established and thus cannot be compared with alternative common modes of exercise. A total of 22 healthy able-bodied men (n=10) and women (n=12) were enrolled in four discontinuous submaximal graded exercise tests. Each test consisted of seven bouts of 3 min exercise ranging from 20 to 45 W and was performed on, respectively, the Cruiser ergometer, a bicycle ergometer, a handbike, and again the Cruiser ergometer. Cardiorespiratory parameters were measured and rate of perceived exertion was determined. Gross mechanical efficiency (GE) was determined from power output and submaximal steady-state energy cost. Repeated-measures analysis of variance (P