PEDIATRIC ORIGINAL ARTICLE Physical activity guidelines and preschooler’s obesity status S Vale 1 , S Trost 2 , JJ Ruiz 3 , C Re ˆgo 4,5 , P Moreira 1,6 and J Mota 1 AIM: The benefits of promoting physical activity (PA) in counteracting the high prevalence of childhood obesity have become increasingly important in the past decade. The aim of this study was to examine the association between compliance of daily PA recommendations and the risk of being overweight or obese in preschool-aged children. METHODS: The sample comprised 607 children aged 4–6 years, recruited from kindergartens located in the metropolitan area of Porto, Portugal. Preschooler’s body mass index was classified according to International Obesity Task Force. PA was assessed during 7 consecutive days by accelerometer. Children were classified as meeting or not meeting PA recommendations based on two guidelines: (i) at least 3 h per day of total PA (TPA); and (ii) at least 1 h per day of moderate to vigorous PA (MVPA). RESULTS: The prevalence of overweight and obesity was 23.5 and 10.6% in girls and 17.2 and 8.9% in boys. In all, 90.2 and 97.3% of girls met the X1 h MVPA and X3 h TPA recommendations, respectively. In all, 96.2 and 99.4% boys met the X1 h MVPA and X3h TPA recommendations, respectively. Boys were significantly more likely to achieve the X1 h MVPA and X3 h TPA recommendations than girls (Pp0.001). Not meeting the X1 h MVPA guideline was associated with obesity status (OR: 3.8; IC: 1.3–10.4), in girls, but not boys. No other statistically significant associations were found. DISCUSSION: These findings suggest that over 90% of children met the recommended guidelines. There is an association with low levels of MVPA and higher obesity status among preschool girls. Further, longitudinal studies are needed to confirm these data. International Journal of Obesity (2013) 37, 1352–1355; doi:10.1038/ijo.2013.109 Keywords: physical activity; preschool children; body fat mass; guidelines; accelerometer INTRODUCTION The prevalence of childhood obesity has been rising during the last two decades. In 2010, the World Health Organization estimated that globally, 42 million children under 5 years of age were overweight or obese. 1 In Portugal, there is a high prevalence of overweight and obese children 2 and adolescents. 3 Patterns of physical activity (PA), sedentary time and nutrition appear to have an important role in long-term weight regulation. 4 In addition, it has been suggested that sedentary time during the first decades of life is linked to several health-related risks during adulthood. 5 Hence, the benefits of reducing sedentary lifestyle and promoting PA have become increasingly important for public health. 6,7 Moreover, childhood and adolescent overweight is strongly associated with adult obesity. 8,9 Recent PA guidelines from UK, Australia and Canada recom- mend that preschool children accumulate at least 3 h of PA across an entire day. 10–12 In addition, the Canadian guidelines recommended that preschool children accumulate at least 1 h of moderate to vigorous PA (MVPA) daily. 12 The accurate assessment of PA is extremely important when examining the relationships between PA and health. Accelerometry has become a commonly used and accepted measure of PA and is the preferred method over the last decade on epidemiological studies in young children. However, relatively few studies have examined the association between PA and obesity status in preschool children 13–17 and to the best of our knowledge, no studies have compared the compliance of daily PA recommendations and obesity status in this age group. Therefore, the purpose of this study was to determine compliance with current PA guidelines in Portuguese preschool children and examine the association between meeting daily PA recommendations and weight status. MATERIALS AND METHODS Participants and data collection This was a cross-sectional study completed in kindergartens enrolled in the Preschool PA, Body Composition and Lifestyle Study (PRESTYLE), a longitudinal study that began in autumn 2008. All kindergartens located in the metropolitan area of Porto were invited to participate. Of those accepted, 20 classrooms were selected. All children belonging to the selected classrooms were invited to participate. A random sample of 1160 children, aged 2–6 years, was recruited from kindergartens located in the metropolitan area of Porto, Portugal. In this study, we included only children aged 4 to 6 years old who had 7 complete days of accelerometer data and had height and weight information. The final sample included 607 healthy preschool children (48.5% girls). Data collection took place between April 2009 and November 2010. Informed written consent was obtained from parents and school supervisors. Study procedures were approved by the Portuguese Founda- tion for Science and Technology and by the Scientific Board of Physical Activity and Health PhD program. Anthropometric measures Body mass and height were measured by standard anthropometric methods. Body mass was measured to the nearest 0.10 kg, with participants lightly dressed (underwear and t-shirt) using a portable digital 1 Research Centre in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports of University of Porto - FADEUP, Porto, Portugal; 2 School of Human Movement Studies. University of Queensland, Brisbane, Australia; 3 Department of Physical Education and Sport, School of Sport Sciences, University of Granada, Granada, Spain; 4 Faculty of Medicine, University of Porto, Porto, Portugal; 5 Children and Adolescent Centre, CUF Hospital, Porto, Portugal and 6 Faculty of Nutrition, University of Porto, Porto, Portugal. Correspondence: Dr S Vale, Research Centre in Physical Activity, Health and Leisure (CIAFEL), Faculty of Sports, University of Porto, FADEUP, R.Pla ´cido Costa, 91, Porto 4200 450, Portugal. E-mail: susanavale@hotmail.com Received 23 March 2013; revised 3 May 2013; accepted 20 May 2013; accepted article preview online 12 June 2013; advance online publication, 2 July 2013 International Journal of Obesity (2013) 37, 1352–1355 & 2013 Macmillan Publishers Limited All rights reserved 0307-0565/13 www.nature.com/ijo