Effects of combined physical training on cardiac autonomic modulation in women with breast cancer undergoing chemotherapy

• Grant number: 23/10258-7
• Support Opportunities: Scholarships in Brazil - Support Program for Fixating Young Doctors
• Start date: August 01, 2023
• End date: December 31, 2025
• Field of knowledge: Health Sciences - Physical Education
• Agreement: CNPq
• Principal Investigator: Miguel Soares Conceição
• Grantee: Marina Lívia Venturini Ferreira
• Host Institution: Universidade São Francisco (USF). Campus Bragança Paulista. Bragança Paulista , SP, Brazil
• Associated research grant: 23/01556-4 - Effects of combined physical training on cardiac autonomic modulation in women with Breast Cancer undergoing chemotherapy, AP.R

Abstract

Introduction: Breast cancer is the most identified neoplasm in women worldwide and the second leading cause of cancer mortality. Due to advances in treatment, breast cancer mortality has been decreasing, increasing patient survival. However, new antineoplastic therapies increase susceptibility to cardiovascular disease, one of the leading causes of death in breast cancer survivors. Changes in autonomic modulation have been shown to be an early marker of morbidity and mortality related to cardiovascular diseases, with heart rate variability (HRV) being a non-invasive tool associated with changes in the autonomic nervous system. The very activation of the sympathetic nervous system may contribute to the onset and progression of cancer, but antineoplastic therapies have also been associated with autonomic changes. Physical training is considered a positive regulator of the autonomic nervous system in healthy patients, but in cancer patients the time course of autonomic dysfunction after exposure to antineoplastic therapies is still unclear. Likewise, little is known about the effects of a systematized combined training (CT) program on the autonomic modulation of patients with breast cancer. Aim: To determine the effect of CT performed in the period between the diagnosis of breast cancer and before starting treatment on cardiac autonomic modulation in women with breast cancer. Methods: 100 women with breast cancer with indication for neoadjuvant chemotherapy will be allocated in one of the following groups: CT before chemotherapy (TC, n=50) or control group (GC, n=50). HRV assessments will be performed before CT, after CT, at each chemotherapy cycle and after 3 months of chemotherapy. Body composition assessments by dual-energy X-ray absorptiometry (DXA); muscle strength through the one repetition maximum test (1-RM); and aerobic fitness through the direct test of maximum oxygen consumption (VO2max) will also be performed before and after the CT program. The CT protocol will consist of strength training (ST: 8 exercises, 1-3 sets of 8-12 RM at 80-90% of 1-RM and 2 min between sets) followed by aerobic training (AT: 3-4 sets of 3 min at 90% of VO2max for 3 min of active recovery (30% of VO2max) on the cycle ergometer, performed 3 times a week. Expected results: If the hypotheses of this project are confirmed, patients with breast cancer can be guided perform CT before starting treatment, as a way to avoid harmful changes in cardiac autonomic modulation and minimize the adverse effects caused by breast cancer treatment, reducing the chances of developing cardiovascular diseases after treatment.