Effects of Exercise on Cancer Treatment Completion and Efficacy

Abstract

Exercise during cancer treatments improves physical fitness, symptoms, and quality of life in several cancer patient groups; however, its effects on treatment completion and response are largely unknown. Here, we review the preclinical and clinical evidence of the potential effects of exercise on cancer treatment completion and efficacy. We first propose a framework to highlight the clinical pathways via which exercise during cancer treatment may impact cancer outcomes. We also discuss the potential complex interactions between exercise and cancer treatment efficacy. In terms of cancer treatment completion rates, there is preliminary evidence that exercise may improve chemotherapy completion in early stage breast cancer patients; however, very little research has examined other cancer treatment modalities or patient groups. In terms of cancer treatment efficacy, preclinical studies have demonstrated that exercise alone may have positive, neutral, or even negative direct antitumor effects. Moreover, when combined with a chemotherapy agent, exercise may enhance or interfere with treatment efficacy. Several clinical trials have demonstrated that exercise during chemotherapy may improve treatment outcomes; however, these trials were not designed to answer this question. Further research is needed to determine whether exercise during cancer treatment has any meaningful effects on cancer treatment completion and efficacy.