Effects of a 12-Week Supervised Exercise Program on Quality of Life, Functional Capacity, and Biological Parameters in Women with Breast Cancer: A Prospective Pilot Program

<b>Objective</b>: Physical exercise is an effective supportive strategy in oncology, yet its implementation remains limited, particularly in patients with metastatic breast cancer. This prospective pilot program aimed to evaluate the effects of a 12-week supervised multicomponent exercise program on quality of life, functional capacity, and biological parameters in women undergoing treatment for breast cancer. <b>Methods</b>: Prospective single-arm pilot program. In total, 44 women with early or metastatic breast cancer were enrolled; 29 completed the full intervention and assessments. The program consisted of supervised aerobic, resistance, mobility, and neuromuscular training three times per week. Quality of life was assessed using the EORTC QLQ-C30 questionnaire. Strength, body composition, functional mobility (Functional Movement Screen, FMS), 6 min walk test (6MWT), and laboratory markers (RDW, HDL, and cholesterol profile) were evaluated pre- and post-intervention. <b>Results</b>: Significant improvements were observed in global quality of life (+19.5%, <i>p</i> = 0.002), physical function (<i>p</i> = 0.006), emotional function (<i>p</i> = 0.003), and fatigue reduction (<i>p</i> = 0.007). The FMS total score increased significantly (<i>p</i> = 0.001), and 6MWT distance improved by 110 m (<i>p</i> < 0.001). Biochemical analyses showed a significant reduction in RDW (<i>p</i> = 0.005), a pro-inflammatory marker, and an increase in HDL cholesterol (<i>p</i> = 0.007). The intervention was well tolerated, with no exercise-related serious adverse events and high adherence to the supervised program. <b>Conclusions</b>: A 12-week supervised exercise program is feasible and beneficial for women with breast cancer, including those with metastatic disease. It is associated with improvements in quality of life, functional mobility, and selected markers of systemic inflammation. These findings should be considered exploratory and support the integration of structured exercise into routine oncologic care, pending confirmation in larger controlled studies.