Secular Trends in Physical Activity Compliance and Sleep Duration in Korean Adults : Findings from the 2018–2023 KNHANES

Purpose: This study examines secular trends in adherence to physical activity guidelines and sleep duration among Korean adults from 2018 to 2023. It also evaluates whether the association between meeting physical activity guidelines and achieving the recommended sleep duration changed over the survey years. Method: This study utilized data from 32,592 participants in the Korea National Health and Nutrition Examination Survey (KNHANES) collected from 2018 to 2023. For the analysis, weekly physical activity levels were calculated, and sleep duration was assessed using average hours per day. The complex sampling design of KNHANES uses strata, clusters, and sampling weights. Linear and quadratic trends in physical activity and sleep duration were examined using orthogonal polynomial coefficients. The association between meeting physical activity guidelines and recommended sleep duration was assessed using multiple logistic regression. Changes in effect sizes across survey years were further evaluated using meta-analysis with Comprehensive Meta-Analysis software. Results: Mean sleep duration declined from 7.01 hours per day in 2018 to 6.65 hours per day in 2023 ( p for linear trend < .001). In contrast, no significant linear or quadratic trend was observed in the prevalence of meeting physical activity guidelines over the study period. Across all survey years, individuals who met physical activity guidelines had lower odds of achieving recommended sleep duration compared with those who did not (OR = 0.89, 95% CI: 0.83–0.96). This association remained consistent over time. Conclusion: From 2018 to 2023, the average sleep duration among Korean adults decreased, whereas adherence to physical activity guidelines remained stable. The inverse association between meeting physical activity guidelines and achieving the recommended sleep duration showed no secular change during the study period.