College of Public Health and Human Sciences

Children and adolescents accrue substantial health benefits by engaging in 60 minutes or more of moderate or vigorous physical activity (MVPA) 5 or more days per week (eg, improved physical and psychological health, prevention of chronic diseases).1, 2, 3, 4 Nevertheless, many Chinese youth are not very active, especially outside of school. For example, although a large majority of school children (72%) appear to participate in in-school MVPA, only a small percentage appear to do so outside of school (≈8%).5 Physical inactivity and sedentary living also are risk factors for developing overweight and obesity, which are growing problems among Chinese youth.6, 7 Specifically, between 1993 and 2009 the prevalence of obesity among Chinese children and adolescents more than doubled, from 6.1% to 13.1%.8

Starting in the 1980s, China's extensive economic reforms have led to rapid industrialization and urbanization, which have exerted an unhealthy impact on the living environment (including air pollution, desertification, loss of biodiversity, and water pollution).9 In addition to adverse environmental impacts, industrialization also is linked to adverse health impacts on children. For example, according to the World Health Organization, 36% of deaths among children worldwide are attributable to environmental problems, and 43% of the total environmental burden of disease falls on children younger than 5 years old.10 In 2010, ambient air pollution in China was ranked the fourth leading risk factor for mortality, contributing to 1.2 million premature deaths, nearly 40% of the global total.11