Abstract Background Cardiovascular disease (CVD) remains the leading cause of morbidity and mortality worldwide. This study aimed to investigate the dose–response relationship between leisure-time physical activity (LTPA) and cardiovascular health, assessed by heart age and predicted 10-year CVD risk, and explore the mediating role of inflammatory regulation. Methods This cross-sectional study included 6658 individuals aged 30–74 years from National Health and Nutrition Examination Survey 2015–2018. Heatmap visualization assessed variable distributions, while generalized linear regression models (GLMs) and restricted cubic splines quantitatively examined the LTPA-cardiovascular health associations. Results Heatmap visualization revealed that, among the 26 variables evaluated, LTPA was inversely associated with heart age, predicted 10-year CVD risk, and odds ratio for high CVD risk. GLM analyses indicated that each additional hour per week of LTPA was associated with a 0.17-year reduction in heart age, a 0.07% decrease in predicted 10-year CVD risk, and a 5% lower odds for having high CVD risk. Vigorous-intensity LTPA showed stronger benefits than moderate activity. Systemic inflammation biomarkers significantly mediated the associations between LTPA and cardiovascular health. Conclusions The findings support a dose-dependent cardioprotective effect of LTPA, partially mediated through anti-inflammatory pathways. These results highlight the importance of promoting LTPA, particularly vigorous-intensity activity, for cardiovascular health promotion.
Ding et al. (Mon,) studied this question.