Inclusion Criteria:

• de novo adult liver transplant recipients with a transplant vintage of two to three months
• access to a home freezer (± -18°C)

Exclusion Criteria:

• Aberrant CPET (abnormal low cardiorespiratory fitness is not considered an exclusion criteria), unstable angina, life-threatening arrhythmias, uncontrolled hypertension/diabetes, HbA1c ≥ 9%, severe pulmonary disease (FEV1 < 50%), musculoskeletal disorders not allowing physical training on a cycle ergometer, or any other medical reasons by the physician considered to be a contraindication for moderate or high-intensity physical exercise
• multi-organ transplantation (exception: combined liver-kidney transplant is considered eligible for participation)
• ongoing treatment for malignancies
• unable to understand Dutch
• no access to smartphone and/or computer with internet access
• does not willing to except the general conditions of Coachbox. Preparticipation medical screening (cardiopulmonary exercise testing with 12-lead ECG + stratification of cardiovascular risk factors) will be performed by a cardiologist (Dr. Kaatje Goetschalckx at UZ Leuven).