Physical Activity and Sedentary Behavior Patterns Among Korean Cancer Survivors: A Cross-Sectional Analysis (2017-2021).

: This study examined differences in physical activity (PA) and sedentary behavior among Korean cancer survivors compared to cancer-free individuals from 2017 to 2021 and identified differences based on their cancer treatment status. : We used data for 28,528 adults (1585 cancer survivors and 26,943 cancer-free individuals) from the 2017-2021 Korea National Health and Nutrition Examination Survey. PA and sedentary behavior were assessed using the Korean version of the Global Physical Activity Questionnaire. We examined adherence to aerobic and resistance training guidelines, domain-specific activity, and sedentary time. We also analyzed the descriptive statistics and conducted chi-square tests, the Mann-Whitney U test, and the non-parametric Kruskal-Wallis test, stratified by demographic and clinical subgroups. : Compared with cancer-free individuals, cancer survivors showed significantly lower adherence to aerobic PA guidelines in 2017 ( < 0.01), 2018 ( < 0.05), and 2021 ( < 0.01). Transportation-related activity accounted for the highest share of the total PA (mean: 59.1%). Sedentary time increased among survivors from 8.1 h/day (2017) to 9.0 h/day (2021). In 2021, resistance training adherence was higher among survivors (24.7%) than among non-cancer individuals (22.9%). In the subgroup analyses, male sex, younger age, recent diagnosis, higher income, and living with a spouse were associated with higher adherence. : The findings underscore a clear need to address both PA and sedentary behavior in cancer survivors, irrespective of treatment phase.