Physical activity and cardiovascular health.

Approximately 60 years ago, the observations of Jeremy Morris and colleagues showed that the incidence of coronary heart disease in bus conductors who climbed the stairs of double-deck buses collecting tickets was lower than that of the relatively inactive bus drivers who were sedentary during most of their occupational time. Since then, numerous studies have confirmed the strong association between physical activity and health in diverse populations. The accumulated evidence linking physical inactivity to health prompted the American Heart Association (AHA) to include physical inactivity as a major risk factor for coronary heart disease in 1992. More recently, the AHA included physically active lifestyles as 1 of the 7 goals for ideal cardiovascular health for children as well as for adults. Underscoring the importanceof physical activity as a key health indicator, the Global Cardiovascular Disease Task Force, an international panel of experts in cardiovascular and noncommunicable disease, set a goal of 10% relative reduction in the prevalence of insufficientphysical activity, 1 of the top 4 evidence-based global targets to reduce noncommunicable diseases. Despite the well-established and broadly disseminated evidence linking physically active lifestyles to cardiovascular health and the public health impact of the role of physical activity in reducing chronic disease risk, nationally representative US data continue to indicate that children and adults are insufficiently physically active. For example, in 2011, the proportion of students who met activity recommendations of 60 minutes or more of moderate to vigorous physical activity on 7 days of the week was 28.7% nationwide and declined from 9th (30.7%) to 12th (25.1%) grades. This decline in physical activity observed from the school-age years through adolescence has been documented in previous studies, nationally and globally. Additional observations with individual/clinical and public health implications are the gender and racial/ ethnicdifferencesobserved inpatterns of physical activity behaviors. Specifically, in 2011, more high school boys (38.3%) than girls (18.5%) self-reported meeting the daily and weekly recommended levels of physical activity; self-reported rates of activity were higher in white (30.4%) than in black (26.0%) or Hispanic (26.5%) adolescents. Unfortunately, from a public health perspective, nationally representative recent data for adults are similar to those observed for US children and youth. For example, according to 2012 data from the National Health Interview Survey, 29.9% do not engage in leisure-time physical activity, operationally defined as no sessions of light/moderate or vigorous physical activity of duration of 10 minutes or more. Consistent with previous reports, in the 2012 survey, nonHispanic black and Hispanic adults were more likely to be inactive (39.4%and39.8%,respectively) than their non-Hispanic white (26.2%) counterparts. Taken together, accumulated evidence on the cardiovascular health benefits of physical activity, combined with the physical activity/inactivity prevalence and trend data in children, adolescents, and adults, points to the urgent need for more effective individual/clinical and public health strategies designed to promote this health behavior beginning early in life and extending across the life course. The Centers for Disease Control and Prevention (CDC), consistent with selected recommendations from