Introduction In adult cancer patients, physical activity (PA) and fitness have been repeatedly shown to correlate with, and improve, many mental and physical measures including decreased cancer recurrence and mortality.
Childhood cancer survivors are at an increased risk of many medical and psychosocial conditions in adulthood, including low bone density, obesity, diabetes, cardiovascular disease, secondary tumors, and low quality of life. PA may alleviate all of these simultaneously, yet very few studies had been conducted in this filed to-date, and results were generally disappointing.
Aim To measure the effect of physical activity on aerobic fitness, body composition, bone density, mood and quality of life of young childhood cancer survivors.
Methods After screening 230 medical records of children from the follow-up clinic of the Hemato-Oncologic Department at the Edmond and Lily Safra Children's Hospital, 85 were deemed eligible by inclusion and exclusion criteria and invited to participate; 25 children agreed, and 23 entered the study. Ten were referred to an exercise group, which performed 2–3 exercise sessions per week for 6 months, and 13 maintained their usual lifestyle. At baseline and after 6 months, we measured aerobic fitness by cardio-pulmonary exercise testing; body composition and bone density by DEXA; and health-related quality of life and mood by validated questionnaires (PedsQL and CDI, respectively).
Results Twenty-two children (96%) completed the study. At baseline, exercise and control groups differed only by a higher proportion of children with obesity in the exercise group, with marginal statistical significance (60% vs. 17%, p=0.07). All children had normal bone mineral density and quality of life measures.
Aerobic fitness improved only in the exercise group, with marginal statistical significance (p=0.068). No between-group differences were found in changes of BMI, BMI z-scores, body fat percentage, bone density indices, mood or quality of life.
After pooling both study groups together, significant correlations were found between the change in aerobic fitness and changes in lean body mass (r 2=0.806, p<0.001), femoral neck bone mineral density (r 2=0.604, p=0.022), bone mineral content (r 2=0.542, p=0.037), and social quality of life (r 2=0.572, p=0.016).
Conclusions Exercise training improves aerobic fitness in childhood cancer survivors, yet the small sample size did not allow identification of additional expected benefits. Nevertheless, changes in fitness over 6 months were significantly correlated with measures of body composition, bone health and quality of life.
Childhood cancer survivors should be continuously encouraged to exercise, in order to both improve their immediate well-being, and to decrease their risks for potential late effects of pediatric cancer.
The study was funded by the Israel Cancer Association.