Weather Conditions and Changes in Usual Mode of Commuting to School in Youths

Choices of travel mode for commuting to school and weather conditions have been previously associated. However, it is unknown if the usual commuting mode is modified by specific weather conditions. The aim of the study was to examine if weather conditions modify the usual mode of commuting to and from school in Spanish youth. A total of 6,979 Spanish youths (7-18 years) completed a 5-day survey of mode of commuting to and from school (usual mode and daily choice over the prior week) in autumn, winter and spring (2012-2013). For each week of questionnaire measurements, weather data from the nearest weather station to each school were obtained. Multilevel logistic regression models were used to estimate odds of active travel based on weather and season. Analyses were stratified by the usual mode of commuting to school (usually active vs. usually passive) and age (children vs. adolescents). The 6,979 youths (80% adolescents aged 12-18 years, 51% male) recorded 163,846 discrete journeys. On the journey from school, children and adolescents were more likely to choose an active mode of commuting (all, p<0.001), regardless of usual mode of commuting. Usually active commuters were more likely to actually choose an active mode of commuting (all, p<0.05) on days with higher mean temperature (children only, OR: 1.02, 95%CI: 1.00-1.03), on days with higher mean wind speed (adolescents only, OR: 1.02, 95%CI: 1.01-1.03), and in spring (adolescents only, OR: 1.13, 95%CI: 1.06-1.21). Usually active children were less likely to use active commuting on days with more direct sunlight (OR: 0.98, 95%CI: 0.96-0.99), while for adolescents, days with a higher mean temperature (OR: 0.98, 95%CI: 0.97-0.99) and a higher total precipitation (OR: 0.99, 95%CI: 0.99-0.99), were associated with lower odds of an active mode of commuting (all, p<0.05). Among usually passive commuters, children showed higher odds of active commuting in spring (OR: 1.32, 95%CI: 1.05-1.65), and adolescents on days with higher mean temperature (OR: 1.04, 95%CI: 1.02-1.06) and higher mean wind speed (OR: 1.06, 95%CI: 1.04-1.09) (all, p<0.05). Additionally, in winter, usually passive adolescents were less likely to choose an active mode of commuting (OR: 0.77, 95%CI: 0.64-0.92, p<0.05). Some deviations from the usual mode of commuting were associated with weather conditions, specifically increased odds of active travel among usually passive children and adolescents in warmer weather. Periods of warmer weather might be beneficial times to promote active travel options to usually passive commuters.