[Comparison of bicycle ergometry and step-ladder exercise (author's transl)]

Repeat exercises (three hours apart) on a bicycle ergometer and a vertical step-ladder were performed in a randomised series on 79 subjects: 13 doctors, 44 patients and 22 sportsmen. Duration of exercise was on average 250% longer in the three groups on the step-ladder than the bicycle. Correspondingly, exercise-pulse sums, recovery-pulse sums and exercise indices were two-and-a-half to three times higher than on bicycle ergometry. As a sign of comparability of the exercise by the two methods there was, on average, no significant difference with regard to the final heart rate, although duration of exercise was longer on the step-ladder. 67% of subjects discontinued the exercise because of peripheral muscle fatigue on the bicycle ergometer, compared with only 8% on the step-ladder. During bicycle ergometry lactate concentration rose by 6.7 mmol/l compared with only 0.78 mmol/l during step-ladder exercise. These results indicate that the value of bicycle ergometry exercise is limited by muscle fatigue in the legs: step-ladder exercise can be extended much longer. The practical significance is that patients with coronary heart disease especially have symptoms and/or ECG changes of ischaemia only at higher levels of physical exercise.