The Role of Physical Activity in Moderating Psychopathological Symptoms and Quality of Life Among Adult Cancer Survivors: A Cross-Sectional Study.

: Several studies indicate that physical activity is both safe and beneficial for most cancer survivors-before, during and after treatment. These benefits include improved mental health and a subsequent positive impact on quality of life. This study aimed to (1) assess the mental health of cancer survivors in terms of depression and anxiety, (2) analyze levels of physical activity within the sample, and (3) explore the relationship between psychopathological symptoms, physical activity, and perceived quality of life. : This is a cross-sectional study of 55 cancer survivors, with a mean age of 62.27 ± 11.91, living in inland of Portugal and not undergoing palliative care. Data were collected using a sociodemographic, clinical and physical activity questionnaire, the Patient Health Questionnaire (PHQ-9), the Generalized Anxiety Disorder scale (GAD-7), the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core-30 (EORTC QLQ-C30), and the Godin Leisure-Time Exercise Questionnaire (GLTEQ). Data was analyzed using descriptive statistics, Cronbach's coefficient to assess the internal consistency, Spearman's correlation, and multiple linear regression. : The results revealed significant associations between physical activity, psychopathological symptomatology, and quality of life. Specifically, the interaction between depression and physical activity had a negative impact on quality of life (B = -0.181; 95% CI -0.291 to -0.070; = 0.002), whereas the interaction between anxiety and physical activity showed a positive effect (B = 0.165; 95% CI 0.037 to 0.293; = 0.013). : Physical activity enhances the quality of life of cancer survivors and moderates the negative impact of psychopathological symptoms. This highlights the importance of promoting healthy lifestyles and empowering healthcare professionals to recommend supervised physical activity as part of integrated and personalized care. Further studies should explore the relationship between other psychopathological symptoms, such as somatization, and physical activity in relation to quality of life.