Haemato-oncological diseases and their treatment are associated with many side-effects. The most common is an enormous level of fatigue. This fatigue is a multidimensional, subjective and objective physiological condition characterised by a persisting and extreme exhaustion. Effective way to eliminate fatigue is inclusion of physical activity into the daily habits. The paper is presenting case study - a patient with Hodgkin lymphoma and following secondary Acute Myeloid Leukaemia treated by bone marrow transplantation. Who was undergoing two years lasting physical activity intervention. The positive impact of PA was verified on selected physiological variables. The Bioelectrical impedance analysis, maximal oxygen consumption, maximal performance, spectral analysis of heart rate variability and haemoglobin concentration was chosen. Despite persisting anaemia, throughout the whole course of exercise intervention, the level of physical fitness and activity of autonomic nervous system has been gradually increasing. The patient has shown a significant improvement in all observed parameters.