Changes in physical activity, sedentary behavior, and self-reported cognitive function in cancer survivors before and during the COVID-19 pandemic: A cross-sectional study

•Cancer survivors who were diagnosed or treated ≥5 years ago, and who had a desirable change in activity since the start of the COVID-19 pandemic reported better perceived cognitive abilities than those who had an undesirable change.•Lifestyle interventions should encourage long-term cancer survivors to break up prolonged periods of sitting and to meet physical activity guidelines to mitigate cancer-related cognitive impairment.•Targeting sedentary behavior and physical activity is an essential health and research priority during the COVID-19 pandemic. Physical activity (PA) and reductions in sedentary behavior (SED) may mitigate cancer-related cognitive impairment. The purpose of this study was to examine (a) the associations between changes in PA, SED, and cognitive function in cancer survivors before and during the coronavirus disease 2019 (COVID-19) pandemic; and (b) clinical subgroups that moderate this association. A cross-sectional survey was administered online to adult cancer survivors globally between July and November of 2020. This was a secondary analysis of a cross-sectional survey examining changes in self-reported PA and quality of life in cancer survivors before and during the COVID-19 pandemic. Self-reported Questionnaires assessed moderate-to-vigorous PA (MVPA) using the modified Godin Leisure Time Exercise Questionnaire, cognitive function using the Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog) scale, and SED using the Domain-specific Sitting Time questionnaire. Cancer survivors were classified into no change in behavior, desirable change (i.e., increase MVPA to meet PA guidelines or decrease SED by ≥60 min/day), and undesirable change (i.e., decrease MVPA to