The paper discusses metabolic and cardiovascular parameters during walking with above-knee prosthesis in patients after amputation due to vascular causes. According to the measured parameters, walking is ranged at the level of moderate physical activities. During walking, non-malignant arrhythmia, asymptomatic ECG criteria for coronary ischemia and especially highly increased blood pressure are frequently observed. Due to long periods of low physical activity before and after the surgery as well as comorbid heart diseases, the risk of proximate cardiac events during gait training and walking with above-knee prosthesis is high. Therefore, accurate evaluation of cardiovascular ability is necessary before prosthetic fitting. At the Institute for Rehabilitation, Republic of Slovenia (IRRS), submaximal stress testing on an. arm ergometer The difference between the calculated oxygen consumption during stress testing and during the 6-minute walk test is not statistically significant.