Effects from physical exercise on reduced cancer-related fatigue: a systematic review of systematic reviews and meta-analysis

Background: Cancer-related fatigue is one of the most prevalent and distressing symptoms among cancer patients, resulting in a great cancer research challenge. Numerous systematic reviews of physical training interventions have been conducted to find the most effective approach. However, evidence remains fragmented, and in which cancer population physical training is more effective than other populations is still unclear. Thus, this study critically appraised systematic reviews and meta-analyses on physical training to reduce adults’ cancer-related fatigue. Methods: A systematic review of systematic reviews and meta-analysis (PROSPERO: CRD42020189049), assessing the efficacy of exercise training for reducing cancer-related fatigue in adults, was conducted in PubMed, CINAHL, Cochrane Database of Systematic Reviews, and the Database of Abstracts of Reviews of Effects, and Pedro. The selected studies (standardized mean difference, SMD; 95%CI), was quantitatively pooled using a random-effects model. Heterogeneity was tested using chi-squared (Q) and I-square statistics (I 2). Results: Of 1438 identified articles, 11 met the inclusion criteria, and ten were meta-analyzed. The results yielded a positive effect of physical training on fatigue in all cancer populations, SMD = −0.33 (−0.43, −0.23). Subgroup analysis based on tumor localization showed a slightly higher physical training effect on fatigue in adults with breast cancer, SMD = −0.36 (−0.57, −0.15), and prostate cancer SMD = −0.34 (−0.45, −.0.22). Conclusions: Our analysis demonstrated some potential improvement in cancer-related fatigue in adult patients undergoing physical training during and after cancer treatments, particularly in patients with breast or prostate cancer.