Health Promotion Journal of Australia 2012: 23(3) 201 Introduction Participation in regular physical activity is associated with enhanced health and reduced risk of mortality and morbidity. 1 Promoting physical activity is an established health promotion priority, and as important as other non-communicable disease risks such as smoking and high blood pressure. 2 Population patterns of physical activity are influenced by the physical and built environments, as well as individual cognitive and social determinants. 1,3 Health promotion initiatives to promote physical activity have typically involved education and communication activities to promote awareness and motivation, and/or collaboration with sectors responsible for urban infrastructure and transport, to ensure there are facilities and infrastructure conducive to physical activity. While climate is a further factor known to influence physical activity, it is not directly amenable to intervention. 4 In terms of the built environment, adults tend to be more active if they live in urban settings that have mixed land use, well-connected street networks and high residential density. 5 There is also some evidence that proximity to recreational facilities and aesthetically pleasing environmental factors may positively influence physical activity. 6 In a study across 11 countries, neighbourhoods with activity-friendly characteristics had significantly higher rates of health-enhancing physical activity compared with those with no supportive attributes. 6 Health promotion has sought to influence cities’physical infrastructure in the interests of population health through the ‘Healthy Cities’ movement. 7 The Healthy Cities approach, established in the mid- 1980s, seeks to encourage intersectoral health promotion efforts to create social, physical and economic environments conducive to health on an urban scale. 8 Based on the idea of the city as a unit of analysis and intervention, this paper seeks to compare Australian cities in terms of population participation in physical activity, and trends in participation. While there are numerous published sources of population data on Australians’ patterns of physical activity, this information is rarely analysed at city level, or compared between cities. The aim of this paper is to rank Australian cities, in terms of population participation in any physical activity undertaken for exercise, recreation or sport (leisure-time physical activity) and to observe temporal trends in leisure-time physical activity (LTPA) in people over 15 years of age between 2001 and 2009. Abstract Issue addressed: Despite recognition that urban infrastructure influences physical activity, there have been no comparisons between Australian city-level patterns of physical activity. This study ranked Australian cities in terms of adults’ participation in leisure-time physical activity and examined city-level variations in activity trends between 2001 and 2009. Methods: Data on participation in leisure-time physical activity in adults (≥15 years) between 2001 and 2009 were obtained from the Exercise Recreation and Sport Survey (ERASS), a computer-assisted telephone interview conducted to collect population-level sport participation information by the Australian Sports Commission. Data were analysed for respondents residing in the eight capital cities of Australia. The prevalence of meeting recommended ‘health-enhancing physical activity’ (HEPA) and levels of walking were calculated by age, gender and survey year. Multiple linear logistic regression analyses were used to compare cities. Results: Pooled data from 174,323 adults across years showed that Melbourne, Brisbane, Perth and Canberra residents were significantly more active than Sydney, Adelaide and Hobart residents in terms of HEPA. Hobart, Perth and Melbourne residents were significantly more likely to walk ≥5 sessions a week compared with their counterparts in other cities. HEPA and walking increased across most cities between 2001 and 2009. Conclusion: There are significant differences between Australian cities in physical activity and walking levels, over and above differences attributable to age, gender or educational levels. While this may be due to infrastructure differences, comparative information on indicators of the built environment and transport infrastructure are not available. Key words: physical activity, healthy cities, active living Health Promotion Journal of Australia 2012; 23: 201-7 So what? Healthy city indicators that compare urban infrastructure and urban policy could stimulate action for more conducive physical activity environments across Australian cities. Active, healthy cities – how does population physical activity vary between Australian cities? Adrian Bauman, Nada Curac, Lesley King, Kamalesh Venugopal and Dafna Merom Physical Activity and Diet