ABSTRACT
BACKGROUND: Physical inactivity has been a great public health concern among breast cancer survivors (BCS), especially during the COVID-19 pandemic, as it is closely related to a higher risk of cancer recurrence and mortality. The positive impacts of psychosocial beliefs in promoting physical activity (PA) have been well acknowledged. Therefore, this study aimed to explore the effects of psychosocial beliefs on PA in BCS to prevent physical inactivity. Furthermore, we examined the relationships between daily activities, trip behaviors, and associated subjective well-being. METHODS: This study used a cross-sectional, descriptive study design. Female BCS who were able to exercise regularly completed the battery of assessments in March 2021. Specifically, the international PA questionnaires and the adapted PA-related psychosocial beliefs questionnaires were used to assess BCS's PA and psychosocial beliefs, respectively. In addition, the smartphone-based Day Reconstruction Method was utilized to measure subjective well-being. Data were analyzed using descriptive statistics, Chi-squared test, analyses of variance, and correlation analysis. RESULTS: In the context of investigations during the COVID-19 pandemic, our study showed that 77.8% of BCS reported meeting PA guidelines. As the components of psychosocial beliefs, the change strategies, social support, and confidence were significantly associated with higher PA levels. Additionally, the protective effect of leisure/recreation activities among BCS on their emotional well-being was observed. CONCLUSIONS: Overall, this study demonstrated the importance of understanding the relationship between BCS's psychosocial beliefs and PA during the pandemic. Notably, this study is unique because it used an application-based method to assess BCS' subjective well-being objectively.