Despite recommendations that patients with breast cancer ought to undertake physical exercise, a majority of breast cancer patients fail to change their lifestyle and to increase their physical activity following diagnosis. In this clinical intervention feasibility study, compliance and sustainability of a walking training program over 24 weeks in patients with breast cancer following treatment were examined. The endpoints were retention rates after 12 and 24 weeks (6 months) and serum levels of glucose metabolism, the total activity score, endurance, a subjectively perceived exertion-during-endurance stress test, quality of life and fatigue. A supervised walking training session for 60-75 min twice-weekly over 6 months in 35 patients with breast cancer following treatment was examined. The study retention at 12 weeks was 27/35 (77%), and at 24 weeks 24/35 (69%). After 24 weeks, the glycated hemoglobin (HbA1c) score was significantly lowered following the intervention (P=0.001). Insulin and glucose levels remained unchanged. Significant improvements were measured in the patients' body mass index (P=0.001), endurance (P=0.013) and in psychological parameters such as fatigue (P=0.008) and the quality of life (P=0.007). Furthermore, the patients exhibited significant improvements in their subjectively perceived exertion during an endurance-stress test (P=0.079) and in their total activity score (P=0.931). The present study demonstrated an increase in total activity resulting from the supervised walking training program twice-weekly over 6 months. Significant changes in long-term parameters of glucose metabolism, such as in the HbA1c score, also occurred. Furthermore, significant improvements in physical and psychological parameters were observed.
Keywords: breast cancer; glucose metabolism; sustainability of physical activity.