Background: Relationships between the neighborhood environment and children's physical activity have been well documented in Western countries but are less investigated in ultra-dense Asian cities. The aim of this study was to identify the environmental facilitators and barriers of physical activity behaviors among Hong Kong Chinese children using nominal group technique.
Methods: Five nominal groups were conducted among 34 children aged 10-11 years from four types of neighborhoods varying in socio-economic status and walkability in Hong Kong. Environmental factors were generated by children in response to the question "What neighborhood environments do you think would increase or decrease your willingness to do physical activity?" Factors were prioritized in order of their importance to children's physical activity.
Results: Sixteen unique environmental factors, which were perceived as the most important to children's physical activity, were identified. Factors perceived as physical activity-facilitators included "Sufficient lighting", "Bridge or tunnel", "Few cars on roads", "Convenient transportation", "Subway station", "Recreation grounds", "Shopping malls with air conditioning", "Fresh air", "Interesting animals", and "Perfume shop". Factors perceived as physical activity-barriers included "People who make me feel unsafe", "Crimes nearby", "Afraid of being taken or hurt at night", "Hard to find toilet in shopping mall", "Too much noise", and "Too many people in recreation grounds".
Conclusions: Specific physical activity-related environmental facilitators and barriers, which are unique in an ultra-dense city, were identified by Hong Kong children. These initial findings can inform future examinations of the physical activity-environment relationship among children in Hong Kong and similar Asian cities.