PURPOSE:  The hematopoietic stem cell transplant (HSCT) is considered for patients who are non-responsive to first intention treatments. This process can last between 4-6 weeks and requires complete isolation of the child. Intensive chemotherapy is given to suppress completely the immune system before transplant. Past studies have reported major motor-developmental and growth deficiencies post-transplant. In this case study we evaluate the feasibility, adherence and effect of physical activity (PA) before, during and after an HSCT process. METHODS: Physical capacities, quality of life (QoL) and the daily PA level were evaluated for the 6 yrs. old male subject, 2 months after a diagnosis of a Burkitt Lymphoma stage III. For one-year, PA sessions were offered to the subject twice a week for 5-30 min, at intensities between 4-6 on the Borg Scale.  We reassessed the subject after one-year. RESULTS: The subject participated 67% of the sessions. Eleven sessions during pre-transplant, 26 during transplant and 4 after treatment completion. The main reason for cancellation was “schedules” (32%).  His height did not increase but his body masse increased by 2 kg. The total scoring results from the PedsQL cancer questionnaire increased by 6% for the subject and by 9% for the proxy. The ankle ROM increased by 18°. The vertical jump test increased by 14 cm and the hand grip test increased by 9 kg. Due to the poor physical condition of the child, we were not able to perform the incremental shuttle walk test (ISWT) prior to transplant. Thought, the one-year assessment revealed that the subject was able to reach 90% of his predicted VO_2max for this test. The level of daily PA diminished after HSCT (<30min/day), but the active transportation time doubled (90 min-180min/day) and the sedentary activity time was diminished by more than half (172min-65min/day). No major adverse event occurred
during this study. CONCLUSIONS: Physical activity was safe and feasible before, during and after the HSCT. We could observe positive results on the child’s physical capacities, quality of life and daily PA levels. Larger studies evaluating the long-term effect of PA before, during and after HSCT are needed to conclude on the possible late effects it may have on physical and psychological aspects.