Safety of cardiorespiratory and muscle fitness assessment in two children with leukemia during early chemotherapy.

PurposeLimited data are available on the cardiorespiratory and muscle fitness of children with acute lymphoblastic leukemia (ALL) during chemotherapy. This pilot study evaluated the safety of testing the cardiorespiratory and muscle fitness of two children with ALL at different risk levels in early chem treatment.MethodsTwo girls with low- and high-risk B-cell ALL (DFCI-16-001) took part in two test sessions: T1 (induction, consolidation 1A/C) and T2 (consolidation 2). Each testing session included a maximal oxygen uptake ($\dot{V}$O₂max) exercise test, muscular strength tests, physical activity and quality of life questionnaires, and a semi-structured interview. The parents agreed to these assessments at the start of chemotherapy treatment.ResultsThe participants experienced no significant adverse effects from undertaking the cardiorespiratory and muscular tests, and there was no impact on their chemotherapy treatment schedule. At their post-test interview, both participants reported that thigh pain and fatigue were the most difficult part of the $\dot{V}$O₂max exercise test. Regarding physical performance outcomes, both participants exhibited low scores compared to their gender, weight- and age-predicted $\dot{V}$O₂max and on most strength test values.ConclusionThe physical tests were safely and successfully conducted with these two participants during early chemotherapy.