Effect of a supervised intermittent exercise program on insomnia in breast cancer patients undergoing chemotherapy.

[BACKGROUND] Patients with localized breast cancer receiving adjuvant chemotherapy often experience sleep disturbances, especially insomnia, which significantly impacts quality of life. This study primarily aimed to evaluate the effects of a 12-week exercise program on insomnia, with secondary outcomes on sleep quality, anxiety/depression, fatigue, pain, and exercise adaptation.

[METHODS] In this randomized controlled multicenter trial, 20 women with non-metastatic breast cancer and clinically diagnosed insomnia were assigned to a control or training group. The training group underwent a 12-week supervised intermittent aerobic exercise program during chemotherapy. The primary outcome was objective total sleep time; secondary outcomes included insomnia severity, sleep architecture, sleep quality, anxiety/depression, fatigue, pain, and cardiorespiratory capacity. Assessments were performed before chemotherapy (T-1), at baseline (T0), and post-intervention (T3) using polysomnography, actigraphy, validated questionnaires, and a maximal graded exercise test.

[RESULTS] The prevalence of clinical insomnia increased from 47% before diagnosis to 71% at T-1, reaching 100% at T0. Total sleep time did not increase after training (p = 0.97), although sleep fragmentation decreased. Clinical improvement was observed in physical and activity-related fatigue. Finally, both submaximal exercise adaptation parameters (power and VO/HR) and maximal parameters (power, VO peak, VO/HR) significantly improved.

[CONCLUSIONS] The training did not increase total sleep time, likely due to insomnia's multifactorial origin. However, training yielded beneficial effects on objective sleep quality and exercise-induced adaptation. Future research is needed to investigate the various etiologies of insomnia to develop tailored and personalized management approaches.

[CLINICAL TRIALS NUMBER] NCT04867096.