Exercise intervention in childhood and adolescence hematopoietic stem cell transplantation: the Henkō trial—rationale and design

Hematopoietic stem cell transplantation (HSCT) is associated with toxicities and physical impairments (i.e., muscle atrophy) aggravated by isolation/bedrest. This randomized control trial ( Henkō ) studies the effects of a physical exercise intervention—lasting from hospital admission for HSCT until 8–9 weeks post-discharge—on muscle strength ( primary outcome ), and several fitness/function, clinical burden (i.e., cardiac damage, treatment toxicities, health-related quality of life, among others) and biological (omics, blood immune phenotype, microbiome) variables ( secondary outcomes ) in children/adolescents with cancer undergoing HSCT. We will also assess intervention implementability . At least 60 participants (male/female, 4–21 years, receiving HSCT due to any cancer, showing adequate baseline health status, understanding Spanish language and providing written informed consent) are being recruited from 3 hospitals (Madrid, Spain) and randomly allocated to an intervention or control group. The intervention consists of supervised concurrent (aerobic and resistance) exercise sessions (3–5 days/week) performed inside isolation wards from transplantation until neutrophil engraftment, and thereafter in the hospital gymnasium, and/or at home. It also includes specific inspiratory muscle training (5 days/week). On the other hand, implementability is assessed following a prospective uncontrolled design within the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) evaluation framework. Our hybrid, integrative and multidisciplinary approach enables exploring exercise effects from a holistic perspective. If successful, our findings will support implementation of tailored physical exercise as an integral part of the standard care of children/adolescents with cancer undergoing HSCT. The findings of this project may provide evidence on the importance of supervised concurrent exercise in the context of childhood/adolescent HSCT. NCT06300515.