Cancer type does not affect exercise-mediated improvements in cardiorespiratory function and fatigue

Abstract

Purpose. Despite mounting evidence indicating that exercise training has a positive effect on cancer recovery, the influence of cancer type on the response to exercise training remains uncharacterized. Therefore, the adaptations to exercise training were compared between groups composed of 7 different forms of cancer. Methods. A total of 319 cancer survivors completed fatigue inventories and participated in assessments of cardiorespiratory function, which encompassed aerobic capacity (VO2peak), pulmonary function (forced vital capacity [FVC] and forced expiratory volume in 1 second [FEV1]), and resting blood pressure and heart rate. Participants were divided into 7 groups based on cancer type, including breast cancer (BC, n = 170), prostate cancer and other male urogenital neoplasia (PC, n = 38), hematological malignancies (HM, n = 34), colorectal cancer (CC, n = 25), gynecological cancers (GC, n = 20), glandular and epithelial neoplasms (GEN, n = 20), and lung cancer (LC, n = 12). All participants completed an individualized, multimodal exercise intervention consisting of cardiorespiratory, flexibility, balance, and muscular strength training 3 days per week for 3 months. Following the intervention, all subjects were reassessed. Generalized Estimating Equations with exchangeable working correlation structure was used to model each response; the group by time interaction effect represented the effect of cancer type on exercise-associated improvements. Results. No significant (P >.05) group by time interaction effects were observed between different types of cancer for any parameter. Pre- to postexercise contrasts revealed significant improvements in VO2peak in BC, PC, HM, and GEN at the Bonferroni adjusted significance level (.00714). Heart rate was significantly lowered in the BC and CC groups. Mean fatigue indices decreased by at least 17% in all groups, but these changes were only significant in the BC, HM, CC, and GC groups. Systolic blood pressure decreased significantly in BC and GC, and diastolic blood pressure decreased significantly only in the BC group while pulmonary function remained unchanged in all cancer types. Conclusion. Although trends toward improved cardiorespiratory and fatigue parameters only reached significance in some groups, there were no significant differences between cancer types. This suggests that cardiorespiratory and fatigue improvements following rehabilitative exercise are not dependent on cancer type. Further research investigating alternative physiological parameters are needed to confirm the relationship between cancer type and exercise-mediated rehabilitation.