From Evidence to Implementation: A Clinical Algorithm for Individualized Exercise Prescription in Breast Cancer

Background/Objectives: Exercise is increasingly recognized as an effective supportive intervention in breast cancer (BC), with substantial evidence demonstrating benefits on cancer-related fatigue, physical function, and quality of life. However, despite this strong scientific basis, its implementation in routine clinical practice remains inconsistent. Existing exercise oncology frameworks have primarily focused on screening, risk stratification, and referral, with limited availability of practical tools to guide individualized exercise prescription across the BC continuum. Accordingly, this narrative review aimed to synthesize current evidence to develop a clinically applicable, stepwise algorithm for individualized exercise prescription in women with BC. Methods: Current evidence from randomized controlled trials, systematic reviews, meta-analyses, and international clinical guidelines on exercise interventions in women with BC was synthesized narratively, with emphasis on exercise modality, intensity, progression, safety considerations, treatment phase, and patient-specific factors. Results: Aerobic and resistance exercise are safe and effective across different phases of BC care, including active treatment, survivorship, and advanced disease, with consistent improvements in fatigue, physical function, cardiorespiratory fitness, and health-related quality of life. However, heterogeneity in interventions, patient populations, and clinical contexts limits direct translation into clinical practice. To address this implementation gap, the available evidence was translated into a structured clinical algorithm based on the FITT principle (frequency, intensity, time, and type), treatment phase, risk stratification, patient-specific characteristics, treatment-related toxicities, and safety considerations, allowing individualized adaptation to different clinical scenarios. Conclusions: Exercise should be considered a core component of BC care rather than a general lifestyle recommendation. Bridging the evidence-to-implementation gap requires structured, individualized, and clinically applicable approaches to exercise prescription. The proposed algorithm translates current evidence into a structured clinical decision-support framework that may facilitate the routine implementation of individualized exercise prescription across the BC continuum.