Associação entre prática de atividade física e características do ambiente

Abstract

The individual and public health benefits of physical activity are well documented, as well as the high prevalence of physical inactivity worldwide in all age groups. Understanding the correlates of physical activity is essential for the development of strategies to increase activity levels. In this context, evaluating the environment in which people live is essential. A description of objectively-measured physical activity of children (7 years), adolescents (18 years) and young adults (30 years) was conducted using data from the most recent follow up visit to each of the Pelotas (Brazil) birth cohort studies. All-domains physical activity was assessed with a wrist-worn accelerometer using a 4-7 days of use protocol. Children belonging to the 2004 cohort practiced, on average, 45 minutes of moderate-to-vigorous physical activity (MVPA) per day, whereas this figure was 43 for adolescents belonging to the 1993 cohort. Young adults from the 1982 cohort practiced, on average, only 25 minutes per day of MVPA. Physical activity levels were higher among males than females and among those from higher socioeconomic strata. Within the 1993 cohort, we assessed the association between environmental attributes of the neighborhood and physical activity levels. Each participant of the cohort was geocoded. Street lighting was positively associated with total MVPA. Family income and paved streets were inversely related to total MVPA. Those living nearby the beach had odds three times higher of being active in leisure-time as compared to the others (OR 3.3; 95%CI 1.4; 8.0). Among those in the intermediate socioeconomic group, street lighting (OR 1.2; 95%CI 1.0; 1.5) and proximity to cycle paths (OR 1.8; 95%CI 1.1; 3.0) were positive predictors of commuting physical activity. A detailed study was conducted to map all public open spaces for physical activity practice in the city, but none of the variables created significantly predicted physical activity levels. We observed an unequal geographical distribution of such spaces, with more public open spaces in richer areas and with fewer people. Finally, a systematic literature review was conducted on the association between physical activity and safety from crime. Current evidence does not support a role of safety from crime at influencing physical activity levels - this null finding was confirmed in analyses restricted to women and older adults.