The effect of training interventions on physical performance, quality of life, and fatigue in patients receiving breast cancer treatment: a systematic review

Abstract

Objectives: The primary purpose of this systematic review is to structure the available evidence concerning physical exercise programs and their effects on (1) physical performance outcomes, (2) experienced fatigue, and (3) quality of life (QoL) in patients during the initial treatment for breast cancer. Data sources: A systematic literature search, based upon the PRISMA guideline, up to January 1, 2018, was performed using four databases (Web of Science, Cochrane Library for Clinical Trials, PubMed, and Medline). Study selection: Inclusion criteria were as follows: (1) adults > 18 years; (2) patients with breast cancer undergoing initial treatment; (3) interventions with the aim to influence the patient’s physical activity, QoL, or fatigue; (4) randomized controlled trials (RCTs) of all ages. The selected studies were scored for methodological quality, and data concerning physical performance, QoL, and fatigue were extracted. Twenty-eight RCTs were included. Data extraction: Different treatment modalities during initial treatment were identified (radiation therapy, chemotherapy, and combination therapy), as well as different types of physical training interventions (cardiovascular endurance exercise, strengthening programs, or a combination of both). Therefore, the results were clustered with regard to the above-mentioned grouping; extracting every relevant outcome related to physical performance (6 MWT or VO2peak; grip/muscle strength), QoL (questionnaires), and fatigue (questionnaires). Data synthesis: Different training programs (endurance, resistance, or a combination of both) were found. These programs were applied during different phases of initial treatment. Some programs were supervised while others were home based. Overall, most training interventions provided an improvement in physical performance and a decrease in perceived fatigue. QoL was the outcome variable least susceptible to improvement. Conclusion: Different types of exercise programs are available for rehabilitation purposes of breast cancer patients during adjuvant therapy. Overall resistance training or resistance training in combination with CV endurance training provides the best results, especially on physical performance and perceived fatigue.