This trial will evaluate the effect of prescribed exercise training on quality of life and exercise capacity of patients with advanced heart failure or after ventricular assist device implantation. Furthermore, clinical, laboratory and echocardiographic markers of heart failure, rehospitalization rates and cost-effectiveness will be assessed.

Inclusion Criteria:

• age >17 years
• written informed consent
• chronic end-stage systolic heart failure with or without ventricular assist device
• clinically stable for at least 6 weeks
• prescription of cardiac rehabilitation

Exclusion Criteria:

• addictions or other illnesses that impact the ability to understand the nature, scope and consequences of the trial
• lack of knowledge of German to fully understand study information
• pregnancy, pre-menopausal women
• participation in the rehabilitation program < 80%
• contraindications of cardiopulmonary exercise testing on an ergometer