Background/Aim: This is a report of the 5-year quality of life (QoL) findings of the BREX-study (n=444). Patients and Methods: A 12-month exercise intervention was arranged shortly after adjuvant treatments. Physical activity (PA) was assessed by PA diary, physical performance by a 2- km walking test, QoL by the EORTC QLQC30 and BR-23 questionnaires, fatigue by the FACIT-Fatigue scale and depression by the Beck’s 13-item depression scale (BDI). Results: Participants who improved their PA from baseline to 5-year follow-up were more likely to improve their global health score (RRR=1.02, p=0.016), physical (RRR=1.02, p=0.009), social (RRR=1.03, p=0.013), role functioning (RRR=1.03, p=0.005), and fatigue (RRR=1.02, p=0.002). An improved 2-km walking test was associated to improved global health, physical and role functioning, body image, future perspectives, and fatigue (p=0.011, p<0.001, p=0.001, p=0.021, p=0.012 and p=0.003). No significant difference between the groups was found. Conclusion: Improvement in PA or physical performance yields a positive change in QoL of breast cancer patients.