In September 2018 researchers from the USA published the results of their review of the scientific literature to assess whether exercise improved sleep in women with breast cancer. Fifteen studies were identified, 12 considered to be of excellent quality. 11 of the studies showed an improvement in sleep following exercise and this included all studies involving walking, primarily during the time of chemotherapy. There were inconsistent findings in studies assessing whether yoga, qigong, and dance improved sleep. There is, however, emerging evidence that aerobic exercise improves sleep in women with breast cancer. An analysis of the review findings led the authors to suggest that sleep outcomes may be influenced more by the type and intensity of the exercise rather than the phase of cancer treatment.
Matthews EE et al. Effects of Exercise on Sleep in Women with Breast Cancer: A Systematic Review. Sleep Med Clin. 2018 Sep;13(3):395-417