[133] Although randomized trial data are lacking, this CPG s systematic evidence review yielded an expansive body of observational data whose findings align with the established federal PAGA recommendations. These findings from systematic reviews and pooled analyses of observational data [134-136] and other prospective cohort studies [137-141] demonstrated an association between recommended physical activity levels and a reduction in CV mortality by 21 91% and all-cause mortality by 19 70%. These associations were found in both primary and secondary prevention populations. However, the body of evidence also suggests CV benefits at various doses of physical activity. Based on pooled analysis research of over 600,000 primary prevention patients by Arem et al. (2015), leisure time aerobic physical activity appears to have a dose-response relationship with CV and all-cause mortality.[136] Leisure time activity levels below federal recommendations were associated with a 20% reduction in CV and all-cause mortality compared to no leisure time activity, while activity three to five times the recommended level was associated with a 39% reduction in all-cause mortality and 42% reduction in CV mortality. The dose-response curve demonstrated an upper limit of benefit at three to five times recommended levels, suggesting a ceiling effect on leisure time physical activity benefits.[136] Evidence also indicates a possible benefit to activity levels much lower than federal recommendations. A systematic review and meta-analysis of prospective cohort studies by Chastin et al. (2017) showed a 29% reduction in all-cause mortality in primary prevention patients whose time spent daily in light-intensity physical activity (LIPA) (1.5 3 metabolic equivalent of task [METs]) (i.e., writing, walking 2 mph, slow ballroom dancing, golfing with a cart) was approximately twice that of their counterparts.[142] In the Copenhagen City Heart Study, Schnohr et al. 