Effect of adaptive variable-resistance training on chemotherapy-induced sarcopenia, fatigue, and functional restriction in pediatric survivors of acute lymphoblastic leukemia: a prospective randomized controlled trial

Purpose: With the rising survival rate among children and adolescents with acute lymphoblastic leukemia (ALL), prioritizing patient-centered care to address the long-term effects of chemotherapy through tailored rehabilitation interventions is essential for optimizing their quality of life. The purpose of this study was to investigate the impact of an 8-week intervention using adaptive variable-resistance training (Adaptive-VRT) on chemotherapy-induced sarcopenia, fatigue, and functional restrictions in pediatric survivors of ALL. Methods: A prospective randomized controlled trial included a total of 62 survivors of ALL, aged 12–18 years, and completed maintenance chemotherapy. Participants were randomized into two groups: the Adaptive-VRT group (n = 31), assigned the Adaptive-VRT intervention, and the control group (n = 31), which adhered to the standard exercise protocol. Baseline and post-intervention measurements were undertaken to analyze sarcopenia-related variables (i.e., muscle thickness and muscle strength), fatigue, and functional performance. Results: The Adaptive-VRT group exhibited more favorable changes in muscle thickness [thigh thickness (P <.001; η²_P = 0.32); rectus femoris (P <.001; η²_P = 0.21); vastus intermedius (P =.002; η²_P = 0.15)], and peak concentric torque of quadriceps [at speed of 90°/s (P =.005; η²_P = 0.13), 120°/s (P =.021; η²_P = 0.10), or 180°/s (P =.008; η²_P = 0.11)] in comparison with the control group. Additionally, the Adaptive-VRT group reported lower fatigue levels (P =.031; η²_P = 0.08) and demonstrated better functional performance [6-min walk test (P <.001; η²_P = 0.25), 4 × 10-m shuttle running test (P <.001; η²_P = 0.24), as well as timed up and down stairs (P <.0006; η²_P = 0.18)]. Conclusion: The findings suggest that Adaptive-VRT is a promising intervention for ameliorating chemotherapy-induced sarcopenia, fatigue, and functional limitations in pediatric ALL survivors. Trial registration: ClinicalTrials.gov Identifier: NCT06338020.